Need Help turboing

hey guys,
i have a honda crx with a b16a1 engine and i would like to turbo it but i looked and looked at a lot of different forums and i came across a forum that said that "VTEC+Turbo = a valvetrain that needs replacing every 10,000kays due to the higher strain of forced induction on all the really clever tiny pieces that make VTEC work..." also said this "The question comes down to what the car is for. Why did Mr Honda invent VTEC? So it reduced the need for forced induction and greater fuel economy etc... Everything was done for a very well thought out reason in the Honda engines, and forcing them with air is something they weren't designed to do. better off with a ram pod and some other goodies..."
So, i just wanted to know what u guys think and if i sould sell my b16a1 and get a ZC and turbo it?

boost the b16
and the u dont need to replace ur valve train every 10,000 km....b16's can take up to 19 PSI on stock internals....besides a block gaurd and heap gap. but f ur running 7 PSI then u are okay...
i have a crx fully turbo charged on 7 PSI with a stock motor and i run [email protected] MPH...can u imagin wat a b16 with bost can do....

hey, thanx
but are u sure because a vtec engine controls the air and gas the engine puts in so if i add a turbo will it just add more air and so will the vtec be ok. If yes what turbo brand should i got with what would be the best.

Ya the turbo wont effect the vtec valve train anymore. The only different thing is the addition of another lobe on the camshaft and the oil pressure vtec piston thing. Vtec is just so u can have these small 4 cylinders and put out hp of a v-6, to make more appealing to the average consumer. I guess theres a lot of ways to look at it. Id say go for a turbonetics or Garrett turbo.

19psi on stock internals ??? no way bro..it can be done..but not for long boom boom

more air = more fuel..a turbo kit will come with the correct size injectors for teh turbo and boost you select..so you dont have to worry about all teh extra air due to the added fuel.. and im with GW go Garrett or turbonetics ...Or go with a full kit and will more than likely be Garrett ie: a greddy kit

i was thing of going with a REV HARD turbo kit. What do u thing of these once:

Stage: 2
Use: Street/Track
Boost Level: 7psi
Injector Size: Stock
Horsepower/Torque: +120 / 285 ft/lbs
-Rev Hard Cast Iron Manifold
-Rev Hard T3/T04E Hybrid Turbo(eff. to 450hp)
-Rev Hard Intercooler 27"x 6.5" x3 "
-35mm external wastegate (7psi)
-Vortech Blow Off Valve
-2.25" Aluminized Mandrel Bent Piping
-2.5" Downpipe
-Check Valves
-High Volume Fuel Pump
-Silicone Hoses & Clamps
-Steel Braided -3 Oil Line
-Oil Return Line
-High Pressure Fuel Line
-High Pressure Silicon Hose
-Necessary Vacuum Tee's
-Necessary Vacuum Lines

OR

Stage: 3 HYPO Kit
Use: Track
Boost Level: 15+psi
Injector Size: 990cc (Low Impendence)
Horsepower/Torque: 550+ / 395 ft/lbs
-Rev Hard Tubular Manifold
-Premium Hypo Turbo(550+hp)
-Rev Hard Intercooler (29" x 10" x 3.5")
-Racegate (9-12psi)
-Vortech Blow Off Valve
-2.5" Aluminum Charge Pipe
-2.25" Aluminized Mandrel Bent Piping
-2.5" Downpipe
-High Volume Fuel Pump
-1:1 Fuel Pressure Regulator
-Silicone Hoses & Clamps
-Steel Braided -3 Oil Line
-Oil Return Line
-Necessary Vacuum Tee's
-Necessary Vacuum Lines
Upgrades:


Mild Steel Equal Length Manifold
3" downpipe
990cc Injectors
Pre Programmed MoTeC system w/ wire loom available
*Stage 3 Kit must be used with Engine Management System.


i really wana go with the stage 3 turbo but what do u guys think

Thats great, but lemme point out a few things that aren't so good. That manifold is the crappiest one ever, get a nice stainless steel one. Mild steel will rust and crack pretty soon, especially with intense driving. Check out www.full-race.com. The fuel management on that is just a bandaid fix. You need a good fuel managment like a AEM or hondata. I personally, do not like pre programmed stuff cuz u just dont know if theyre set for ur car. On the other hand, i dont know much about MoTec. If you get that upgrade, the fuel pressure regulator is useless. Then, the injectors. Are 990cc the ones for ur engine, or are u just taking them cuz their big? Cuz theres a lot of math that goes into determining the size of the injectors to use. Last, u might not need to do this, but maybe go w/ a better brand name on the parts, Id susgest finding the best parts somewhere else, and not getting the kit

i am just going with the 990cc injectors because its what comes with the kit.

ok, ur saying that i should build my own turbo kit, ok well i want something like that stage 3 turbo but like u said better. So can u give me a list of parts that i should get to make a kit just like that or better and what type of turbo to use.

You are going to have to do some work to your block if you want to run the hypo stage 3. 15psi is way to much for a stock block. There is also no way the stock stock block can handle 19psi as mentioned above. if you want that kind power, you are going to have to get forged pistions, and rods, probably re-sleeve it and close the deck, and get a good head gasket. The most you should run is 8psi on stock block. There are people who have run 10psi on the stock block sucessfully, but they had a hella good tune. But still can be done. as far as which kit, I would say go custom since you already have a good Idea of what you want. You will see the best power outcomes that way.

i am going to put pistions with a compression ratio of 8.0.something i think its 8.0.5 so what do u think of those pistions.

What rods, head gasket, and block should i use or what is the best to use. With the hypo stage 3 kit that i am going to build.

Heres my list of parts for my planned turbo build

Custom Manifold
Garrett T3/T4 TURBO
Hondata
Custom Downpipe
Tial 35mm Wastegate
HKS Blowoff Valve
Custom Intercooler Piping
Oil Lines
Silicon Hoses
Intercooler
AEM Fuel Rail
660cc fuel Injectors
Apexi Boost Controller

What that premade kit is going to do is add 2 injectors right before the throttle body. I am going to get 4 new ones and use hondata to tune all the fuel curves, then there is no need for those extra injectors.

thanx
but how much power do u think it well make with my b16a1 in my crx

and

how much power do u think it will make then i do Engine Sleeving, new pistions with the CR at 8.0.5 (so i can run high boost), rods, cams, springs retainers, values so in other word do the works and will this turbo kit be good for this

Well you would put the sleeves in to be able to boost higher, it wont really give u any gains if u keep it at the same psi. Same w/ the low comp pistons. All the valvetrain upgrades will make it able to rev higher and the new cam will adjust ur powerband.

If you do get sleeves, I suggest darton or golden eagle sleeves with integrated reinforceing ribs and deck buttress. That will close the deck for you, and strengthen the cylinder walls. That with some, say, crower forged rods, and JE forged pistons, will make that bottom able to handle a crap load of boost. Basically all that doesn't really give you gains, but like mentioned above will allow you to boost high. Look into fuel delivery as well, depending on how much power you want to make, you may need a new fuel pump. The injectors should come with the kit. Anyways with that kit, in a crx you are going to be pretty damn quick, and if you do all the work above, your car will be able to handle alot of boost, and you will be flyin. Don't forget to look at your suspension. You will need to take a look at how you are going to get that kind of power to the weels, also depending on how how you boost, you may have to replace the axles too.

i think i am going to get it sleeved by eagle sleeves but i have a question about the pistons i think the stock CR is like 10.4:1 should i lower that or make it higher will this help to run more boost or what will it do

Lowering your compression will help you boost more. High compression rates are better for N/A ocars, not FI! Also make sure those sleeves have a deck buttress so it closes it for you. I would prablably recomend darton over eagle, but both would be good, if they close the deck.

i am going to go with pistons with a CR of 8.0.1 how much boost would i be able to run with that plus with the engine sleeved. u said to make sure they close off the deck (buttress) what is this and what does it do.

they are BSeries 8.0:1 3.189/81.00mm TURBO/NITROU so they would be good for my b16a1. what do u think of this.

should i just take my car to darton to get it sleeved or should i just get this at a store that i go to get my parts. this is what it is HONDA B16 81mm SLEEVE KIT so is the kit just as good as take it to darton

Sleeving is something a machine shop does... it involves boring(making the cylinders bigger in diameter) the cylinders over a certain ammount, for the engines I'm used to(far far far from hondas) its around 1/4" diameter, then a new cylinder is put in place of it. That is sleeving. Basically replacing a cylinder wall with a stronger one. You have a lot of research to do before you start puttin this thing together. If you don't know exactly what you're doin, something will break.

well, i wana have my b16a be able to run high boost and maybe nos and i wana use piston's with the CR of 8.0.1 so that i can run high boost. What else do i need to look into and what do u think of the CR of those piston's

and what would u recommend

Id recomend taking it one step at a time. Don't run high boost and NOS at the same time, it just leads to bad effects, in my mind. If you are pretty intent on runnng NOS, get an N-tercooler. Its that like oval shapped ring on the intercooler, it sprays nos onto the intercooler to cool it down. You could use CO2, then get a purge kit and be all cool like silver skyline from 2F2f

Don't forget forged rods as well. That is a pretty essential piece of the puzzle! With that strong of a bottom you will be able to run pretty high boost, but don't forget the head. That will need some work as well, as well as the fuel system, ignition, suspension.....! What is your hp goal? that is a good way to start.

8.0 for compression is way to low . . . you are not going to get much power gains per pound of boost as you would if you ran a higher compression such as a 9.5:1 right around there. As far as the 19psi goes hah, good luck on that one. You better have a very good tuner to pull that one off, and even so it won't last very long. There is no need to upgrade your valves etc . . . unless you are a crazy driver that likes to redline a lot and do things like that. Replacing your valves, springs, retainers etc . . . will allow you to rev higher safely.

As for the Rev Hard manifold being shitty it depends on which one. The manifolds that come with the kits are made of "Cast Iron" so they are pretty good. Everything boiuls down to tuning in the end because if your EGT's (Exhaust Gas Temperatures) are to high well your manifold is gona crack anyways, so a lot of factors go into things like that.

Any other questiosn feel free to PM me.

You could run 19 psi w/ sleeves for sure. I know a kid who has an 02 jetta 1.8T. Hes running 17 psi on the stock turbo. Its the only mod he has done to his car. I think hes running like a 14.1 or 14.0

You could run 19 psi w/ sleeves for sure. I know a kid who has an 02 jetta 1.8T. Hes running 17 psi on the stock turbo. Its the only mod he has done to his car. I think hes running like a 14.1 or 14.0

yeah but you gota remember you can't compare any other cars to civics because the cars that come straight from the facotory with turbo are meant to handle boost, and all cars are made differently as far as internals. jetta internals might be stronger then civic internals and what not. Sleeving is not the problem . . . . stock honda sleeves can handle that, but the rods can't . . . the rods are pretty much the weakest point in the honda motor when going into forced induction. I don't want to sound like a jackass or anything, and if I do I don't mean to. I'm just speaking what I know or what I have learned so far, but hey I got a lot to learn and look forward to learning everything I can.

A good example is my friends mitsubishi . . . he's running 19psi and he did no internal work, and since the mitsubishi he has already came boosted from the factory the internals are amde to handle the boost already.

8.0 for compression is way to low . . . you are not going to get much power gains per pound of boost as you would if you ran a higher compression such as a 9.5:1 right around there.

Yes, but the lower your compression is the more boost you can run without detonating. Why are turbo pistons dished? Why to blown nitro drag motors run 6.5:1 compression, when N/A nitro motors run 16+:1 compression? Because less compression means you have more chamber volume to fill with compressed air. This obviously means more power. Go with the 8:1. You'll be able to run more boost and make more power.

well i'm not gona argue . . . . this is a street car not a drag car :-p mid 9's you'll just get better power with less boost. It's all in what the buyers prefrence is because if running 8.1 is better, then why does everyone who is boosted or the majority of the people run mid 9's? You get more out of each lb of boost with slightly higher compression.

It's basically like saying:

8.5:1 @ 20psi = 350hp
9.5:1 @ 14psi = 350hp

that's just an example not exact #'s for anything, but it's all in prefrence you can choose to run less boost and get more power per lb of boost by running higher compression, or run lower compression and run a shit load of boost.

Me personally would go with mid 9's on the compression just my :2cents:

Omfg.. The bs in this thread is just... Let me get to the point, noone wants a 8:1:etc.. compression ratio for their car, and i doubt his going to run that high of boost. Let's be realistic get 9:5:1 compression ratio and run about 12psi and you'll be fine. Nice spoolup on certain turbo's and good power. With a 8:etc.. compression ratio it would take forever to get moving and would be a bitc.. to drive in the city. Those of you who are telling him to get 8:0 compression ratio should be shot.

I'm running 7.5 on my next motor build, intentionally. Even if you run the same ammount of boost, you'll make more power with less compression ratio. Think about it. You have more area to fill with compressed air. Therefore, you'll have more compressed air and fuel when compared to a higher compression engine. So its not compressed quite as much - that tiny bit of compression is nothing when compared to the ammount a turbo compressed the air. You'll make more power with less compression, AND on top of that you can run more boost. Low compression is the way to go. How much power are you going to lose n/a going from 9.5:1 to 8:1??? Maybe 10hp? 15? To gain 50hp on the top end, I say its definately worth it.

you will NOT make more power at the same psi level given the same turbo with lower compression.

Got any proof? theory? I was sure to state why it would.. nows your chance to state why it wouldnt.

Let me explain further, maybe that'd help. A turbo compresses air. A piston compresses air. Whats the difference? Why do turbos make so much more power? First off, the turbo allows you to make your compression skyrocket with the same chamber volume.. how? it displaces more O2 molecules in the same swept volume(area of bore x stroke.. aka displacement). This has nothing to do with static compression really, just simple logic. To compensate for this increase in compression, you can retard your timing to keep from detonating.
Second point, which is the important one here... A N/A engine can only fill maybe a bit more than the displacement of the cylinder(more because of exhaust scavenging and intake pressure wave tuning). But with a turbo, you have a positive pressure, so you can force the air into the entire area of the chamber, not just the area the piston sweeps. In order to attain a lower compression ratio, you need to increase the chamber size. More area to fill will effectively increase the displacement of the motor when using forced induction. On race motors, superchargers work so well because there is so much duration and overlap on the cams they run that they can blow the exhaust remaining in the chamber out... In fact, they overshoot and actually blow some of the intake charge out the exhaust tubes as well, hence the flame throwing effect. This allows them to fill the entire chamber with air and fuel. Some very good turbos can achieve this same effect of exhaust backpressure being less than the intake pressure. This would require a very large exhaust turbine, so a very high spool RPM. The Aerocharger is a good example of a turbo that can achieve this low exhaust backpressure, since it such an incredibly efficient turbo. But normal turbo'd cars with small turbines that don't get this effect still benefit.. They don't have this massive overlap(in fact, normal turbo cars like very little overlap to prevent exhaust reversion because of their higher exhaust pressures), but they still cram more air into the chamber, just not 100% air. Due to inertia of the exhaust on the exhaust stroke, you still get a scavenging effect, thereby reducing the pressure of the exhaust left in the chamber when the exhaust valve closes... so the incoming air still has some extra room in the chamber to occupy. This area is increased when you have a larger chamber to work with.
In addition, running higher compression on the same boost would require you to retard your ignition more than the lower compression approach, further reducing power output.
But this isnt even the point, and is straying from the original question...
The point is, you could run significantly more boost on lower compression, keeping the ignition timing the same for both motors. The difference between 9.5:1 and 8:1 would be around 5psi! Now tell me you wouldn't sacrifice a few HP before the turbo spools for 5 more psi...(who cares about HP @ 3000rpm anyways? whats your HP at 2000-3000rpm? probably in the range of 30-60... Just slip the clutch and launch at 3k or get a 3000 stall converter if you have an auto...
I say get 8:1, and either make significantly more power with 5psi more than 9.5:1, or run 8:1, the same boost, a bit more power, and cheaper gas. But thats just my opinion...

Omfg.. The bs in this thread is just... Let me get to the point, noone wants a 8:1:etc.. compression ratio for their car, and i doubt his going to run that high of boost. Let's be realistic get 9:5:1 compression ratio and run about 12psi and you'll be fine. Nice spoolup on certain turbo's and good power. With a 8:etc.. compression ratio it would take forever to get moving and would be a bitc.. to drive in the city. Those of you who are telling him to get 8:0 compression ratio should be shot.


thank you for backing me up on this. The bottom line is you make less hp per pound of boost with a lower compression ratio and that's the end of the story. That's just the way things go . . . . you can run just as much boost running the 9.5:1 as you can running the 8.5:1 accept you will gain more hp per pound of boost the higher your compression is. It's all in the tuning! Read man! There is someone running a compression ratio of like 11 on a fucking Type R motor boosted @ about 20psi making 650 whp tell you that you can run a compression ratio of 8 with 20psi and make 650whp I highly doubt it, maybe at about 30psi or so.

Ask anyone and they wills traight up tell you that 8.5:1 is ridiculously low for turbo, and you're just starving yourself of power, or should I say you're just giving away easy HP. like I said before you can blow your motor up with 5psi if your tuning sucks, but everyone has their own opinion as to what's better, and I personally think that there is no need to go crazy low on the compression.

If you knew motors you would know that the higher compression car running the same amount of boost will OwN you period.

Research about compression . . . I hate to be an ass but the only reason to go that low on compression is ebcause you are worried about blowing your shit up.

a picture from corky bell's Maximum Boost shows a lovely graph of boost pressure vs compression ratio.
with 92 octane, it shows around 5psi at 9.5:1 compression ratio. At 8:1 it shows 10psi. At 7:1 it shows 15psi... these are approximations just to show the trend in the relationship between boost and compression, the actual psi you can run will depend on the engineering of the specific motor, but the concept still applies. its a logarithmic graph, so the lower the compression ratio drops, the more and more boost you can run. also, as your compression ratio goes up, the ammount the boost goes down gets less and less.
Thats why drag cars only go down to 6.5:1... beyond that would be pointless. They can already run a few bars of boost.

"Research about compression . . . I hate to be an ass but the only reason to go that low on compression is ebcause you are worried about blowing your shit up."
Damn good point. I'm sure the person you're advising doesnt want to blow his shit up either.

I was wrong on the compression ratio w/ same boost though, that concept only works on the supercharged motors. But you still will make more power with less compression since you can run significantly more boost. If higher compression and less boost were better, why would anyone run boost? following that logic, the maximum compression and no boost would be best.
What about the professional drag cars? They try to squeeze every last ounce of power out of their motors, if running a high comp ratio and low boost were good, why do they run 6.5:1? to keep from "blowing their shit up"? hell no, those motors only have to last one run then they're rebuilt! Its done for a reason.

jdmracers, figure out how much power you want, then figure out how much boost it will take to run that, then figure out your compression ratio. Sure if you want to run like 10psi, go with 9.5:1. But if you want to run 15-20+, go with 8:1. I'm planning on low-mid 20s, so I'm goin to 7.5:1. My motor would detonate if I ran any more than 8, so 7.5 is erring on the safe side, and leaving room for more if I ever want it. I dont think I will, 20 should put me north of 800hp...

the goal with forced induction motors is you want the most hp you can get out of it before you boost, but of course your not going to go overboard on the compression ratio. because the more hp you got before boost, the higher your hp per boost is of course this all depends on the octane of the fuel.

if it was me id run 9.5:1 because its not about boost level its more about hp level. pump gas limits are around 400whp so i would want to get to 400whp on as a low boost as possible, also when i decide to up the boost i would make alot of power at higher boost, then the average guy.

its kinda like my friends motor, 450whp at 15psi, where other crvtecs dont make that much whp at that psi. what was it all about, highest hp before the boost, before boost it made 227whp.

the goal with forced induction motors is you want the most hp you can get out of it before you boost, but of course your not going to go overboard on the compression ratio. because the more hp you got before boost, the higher your hp per boost is of course this all depends on the octane of the fuel.

if it was me id run 9.5:1 because its not about boost level its more about hp level. pump gas limits are around 400whp so i would want to get to 400whp on as a low boost as possible, also when i decide to up the boost i would make alot of power at higher boost, then the average guy.

its kinda like my friends motor, 450whp at 15psi, where other crvtecs dont make that much whp at that psi. what was it all about, highest hp before the boost, before boost it made 227whp.

yup yup you got it . . . . as far as the drag people go running 7.5:1 or whatever . . . . these are not drag cars, these are civics here buddy. The 2 do not compare. You can run the same amount of boost on a 9.5:1 as you can on a 8.5:1 motor I can't say the same for 10.5:1 it's been done before believe me, so don't say that you can boost way more on a car that ha a 8.5:1 compression level.

Why would you have a low compression and boost 25psi when I can have a slightly higher compression and run 15psi to achieve the samething or 20psi to achieve the samething? Then if I run the same amount of boost you do on the same care, with the same turbo setup, with just slightly higher compression i'll spank you?

Why do you think I'd achieve the same thing??? Get Maximum Boost by Corky Bell. You'll learn something. It should be required reading for anyone considering turbocharging thier car. Less compression means more boost. More boost means more HP, much more HP than you'd gain with a bit more compression and a lot less boost. Running 15psi and 9.5:1 compression is not going to come close to 25psi and 7.5:1 compression.
Engine Analyzer 3.0 estimates 1028ft/lbs of tq and 964hp with 25psi and 7.5:1 compression; it estimates 914/lbs and 934hp with 15psi. I lost over 110ft/lbs of torque and 30hp. This was with everything else the same except the turbos were tweaked for the different ammount of boost. If I had recammed the motor to suit the higher boost and lower compression, I probably could have squeeze significantly more power out of it. And hey, I could always turn the boost all the way down and run absolute shit for gas and it wont detonate.
By the way, this engine is going in my street car, but obviously I'm not going to run 25psi all the time. Probably barely ever. I'll probably run around 6psi when just driving around.. thats still over 600tq/hp.
Compression ratio also depends a lot on where you're going to be boosting though. I often forget on this forum that these are little high revving hondas, not v8s. Compression ratio becomes less of a problem the higher you spin a motor, so maybe if you're boosting from 4500+rpm, you can get away with the higher compression ratios.. me, I'm boosting from 2500-6000 on a 30 year old v8, so I'm in more danger than you folks.
And I know they're not drag cars.. they're front wheel drive, after all... :)

the goal with forced induction motors is you want the most hp you can get out of it before you boost, but of course your not going to go overboard on the compression ratio.
Not quite. Turbos cause an engine to behave quite differently than N/A. I would never build a motor for the most N/A power and then turbocharge or supercharge it. For starters, cams are dramatically different. If you built a motor for max N/A power, you'd have a pretty big cam with lots of overlap in it.. yet turbos don't like big cams. Small cams with little overlap is a good turbo cam. Another thing is intake/exhaust flow bias. Turbos need more of a bias towards exhaust than you'd want on a N/A motor. Turbocharging is a completely different realm than N/A, if you're going to build an turbo motor, build it from the ground up to be turbocharged. I wouldn't even think about N/A for a moment when building a turbocharged motor. Doesn't it seem like an obviously extraneous step to first build it for N/A, then modify that to turbocharge? Why not just start by building a motor for turbocharging...

here is a general ratio of power with motors.

stock b16 140whp, add 1 bar of boost now his hp should be around 280whp

upgraded b16 200whp, add 1 bar of boost now his hp should be around 400whp

of course this is not exact, this is a very very general illustration of power. theres alot of factors involved. so according to this, wouldnt you want to get as much power as you can before you turbo ? i would. if it were me id go with the biggest cam i could get that would still be streetable.

with building a motor for turbo, of course you know i dont mean doing everything possible with na then turbo it, because i wouldnt bore it too much like a na engine, i wouldnt run high compression like an na, i wouldnt run ITB like an na, etc etc.

and i didnt say build it like an na motor, i said get as much hp as you can get out of it in na form

i do see yoru logic is saying that if you lower the compression you have more room for the compressed air from the turbo and therefore can up the boost. but if you keep lowering the compression ratio and uping hte boost your almost canceling each of them out, you drop the compression ratio and lose power but you boost it to gain alittle more power, what if you were to up the boost but stay at the same compression ratio ? do you think yoru drop in compression hp would be more then staying with the same compression ratio ?

when turboing you want a power goal, why would you want to boost over 30psi to get that desired hp when you could just boost 22psi to get the same results in hp ? it doesnt really make any sense. also when you drop your compression that low it makes it really shitty to drive on the street, but if you keep the compression ratio high it is still fun ot drive on teh street out of boost

You are kinda on the right track, but not necessarily. Boost will give u more power than compression. So if u lower the compression and add boost you will gain more hp than if u were to stay at stock and run low boost. I dont feel like figuring out the math behind it, but if anyone really wants it i will

there is no need to run lower boost with stock compression . . . you will not blow your motor ons tock compression if it is tuned properly. I can boost just as much with aftermarket rods with a 9.5:1 compression as I could at 8.5:1 i'll just achieve more power running the higher compression. You're safe running anything below mid 10's for turbo. What do you think GSR motors compression is? They are mid 10's if I remember correctly and 10psi will net you about 300whp depending on tuning, and turbo size.

But if you are smart you won't take a type r motor and boost it unless you know what you are doing. If you are really good at building motors and tuning well then yes you can get away with boosting a high compression motor.

so what a 7.5 cr at 15psi will yield more hp then a 9.5 cr at 10psi ? would you rather be making xxx amount of hp at 7.5 cr at 30psi, or would you rather be making same xxx hp at 9.5 cr at 20 psi ? i would rather be making it at a lower boost so i could always turn the boost up if i want and not be making some xxx hp at a really high boost over 30+ psi when it could be made in the 20s psi.

but i would like to see some numbers but because we could be going back and forth on this all day, so numbers would help

so what a 7.5 cr at 15psi will yield more hp then a 9.5 cr at 10psi ? would you rather be making xxx amount of hp at 7.5 cr at 30psi, or would you rather be making same xxx hp at 9.5 cr at 20 psi ? i would rather be making it at a lower boost so i could always turn the boost up if i want and not be making some xxx hp at a really high boost over 30+ psi when it could be made in the 20s psi.

but i would like to see some numbers but because we could be going back and forth on this all day, so numbers would help

you siding with me? That's what I am saying . . . . why run a lower compression like 7.5 and make 300 @ 20psi when you can runa 9.5 or even 10 on compression and make the same power at 10psi?! That is my hole point to this debate. The higher the compression the more hp you get per pound of boost . . . . I don't mean run 12.5 for compression but a 10 flat is kewl and you'll be so happy with the power you make!

finally someone that sees things the way I do

No, ur wrong. More boost and less compression is better than high compression low boost. High compression and high boost is best but not stable, especially on a open decked honda block

Okay, I'm tired of writing novel-long posts.. I'll leave it at this, and I hope we can all agree:
Run as much compression as you can for whatever boost you need to achieve your power goals. As the boost needed goes up, the compression has to be reduced to prevent excessively retarding the ignition or detonating.

Don't run big cams on turbo motors, ask anyone, read Maximum Boost.. Turbos like very little overlap. Exhaust pressure on most turbos is higher than intake pressure, with lots of overlap your exhaust pressure will stall the intake charge in the intake while the exhaust valve is open. Obviously the same idea applies that you will have to increase lift and duration to rev higher, but it will be significantly less than a N/A version. The turbo will take care of getting the air in the cylinder, but you'll have to run much more duration and lift on the exhaust side. The higher you spin the motor, the more exhaust bias you should give the motor. Also, if you need high durations in order to spin your motor higher, you should increase the LSA(lobe seperation angle) in order to keep the longer durations from creating long overlaps.

Yes you will make more power if you build your motor up to make lots of N/A power and then turbo it vs. stock turbo'd. But you will make more power than your N/A friend if you build a motor up for turbocharging. it will make less power N/A, but more under boost. This is merely because the ideal turbo cam is not the ideal N/A cam. Its kinda like this... Would you put a 4" intake tube on a stock intake? sure you'll gain power, but not as much as if you upgraded the intake as well. Part matching is the name of the game in making power, and turbos are no different. A group of parts that works well N/A might not work as well turbocharged and vice versa.

Exactly GWInquisitor14. While high compression and high boost is ideal, its just not realistic. You see this kind of thing in cars running nitro or propane or diesel. Gasoline just can't take it. Pure octane has a Octane rating(confusin huh?) of 100.. methanol, nitro, toluene, propane, etc have much higher ratings(not sure of all of them, but should be 110+. Toluene has a rating of 114...). The best stuff you can get at a pump is what, 93? This rating is how much you can compress the fuel before it spontaneously explodes. If you run a high RPM nitro motor with lots of compression and lots of boost, you'll be fine. But I don't think anyone in here is running nitro or toluene or propane. (you think gas prices are high now? A gallon of 20% nitro gas is over 40 bucks...). So we are forced to lower compression to be able to run more boost. Boost makes more power than piston compression. I mean, think about it.. its the same thing! Why have the piston do extra work compressing the mixture, when you can increase the boost and have the turbo do it instead, and get more A/F mixture in the chamber at the same time?

GW, you have no idea what yoru talking about when you say open decked honda blocks, this goes to show how you listen to more rumor then fact which makes your information unreliable. do you know benson sleeves ? do you know he wont make you a closed deck block unless its already closed in stock form, do you know earl from laskey's racing team recommends using benson sleeves which he knows is open deck sleeves. not saying that you shouldnt use a closed deck honda motor but it isnt necessary to close the deck on the block, it will be just fine in open deck form.

and no i dont think we will all agree on that, because you can run any compression you want on any boost level, as long as its within the fuels capacity to keep it safe. liek for example, pump gas, now if i asked you guys how much psi could you run on a block till its outside the levels of pump gas, you probably would say something like 15psi, but then youd be wrong from the beginning because it would be more about the hp numbers, like the limits of pump gas are at around 400hp, there no set amount of psi that you can run but from your statment above, it looks liek you believe that reaching the limit on pump gas is all about boost and not hp.

and again i gotta repeat myself, i didnt say build it to na specs, i said to gain as much hp as you can out of it before its been turboed, in na trim.

What? How can you say its a HP level? That is such an arbitrary fact, its a result of way too many things, only a small piece of which is octane of the fuel! My explorer started detonating on 87 octane late in its life, and that piece of shit made maybe 150hp... my 351c(before it was sabotaged) made over 300hp on the same octane gas! The gas doesnt know how much HP its making, and the reason to run higher octane gas(allow more compression) happens before the cylinders even fire! How can it have anything to do with HP? Maybe because thats the most you've heard of for your particular engine? I'm sure it can be broken, and I'm sure lots of people will break their motors before they even come close to 400hp.
And yes I do believe the limit of pump gas has absolutely nothing to do with HP. None whatsoever.

"and again i gotta repeat myself, i didnt say build it to na specs, i said to gain as much hp as you can out of it before its been turboed, in na trim."
What are you talking about? You're contradicting yourself in the same sentence! You shouldn't even think about N/A HP when you're building a turbo motor, it has nothing to do with turbo'd HP.
It'd help if I knew what you meant by 'get as much hp as you can out of it'.. what would you do?

Look, even if so and so will make u sleeves for a open decked honda block and leave it open, the cylinder walls with those sleeves will be a lot stronger. Honda cylinder walls are very thin. When you put a lot of pressure onto those, they have a chance at cracking. When you blow a ballon up too far, does it explode? Yes, because uve compressed the air too much. Just like in the cylinder, if you add too much compression in it, the weakest part of your engine will blow, whether its the studs and u lift ur cylinder head off the block or the cylinder walls, or the pistons. Theres many places you could break down. Civickiller, have u ever made a high turbo high compression honda engine w/o any internal mods?

your right in a sense that theres alot of facts involved thats why its an hp level, and not a certain psi, or a certain compression, or a certain tune. for example, say you got a d16 motor, fully built and tuned really good, so you start to boost it and say it takes 18psi to get to 400hp, then you go b16, and say it takes 15psi to get to 400hp. at that 400hp your at yoru limit on pump gas, doesnt matter how much boost you run to get it.

but of course this is for fi, and not na because idk if you could get 400hp out of a bseries na motor, sorry i didnt clarify that, that is for boost.

and to maybe help you better understand what im saying when im saying get max hp out of it look at my example. for example in a b series motor, if i were making a na motor, i would bore it out to at least 86mm, and run at least a 12.5 cr, with itb. but with a fi motor, i wouldnt bore it more than 84, i personally would go with 82 or 83 mm bore, my cr would be close to 9.5. your trying to get the most hp out of it as you can but in the same time your building the motor for turbo, im still trying to get max hp out of it, but im doing it keeping in mind that its going to be boosted alot, thats why with the bore i wouldnt go very big because then the cylinder walls get too thin and unsafe for high boost. so with 86 and 12.5 im thinkign max hp for na, but with 84 and 9.5 im thinking max hp for fi. but again im still trying to get max hp out of it before its boosted, in na trim. and how much hp you make before you boost has alot to do with how much hp you get per psi. now do you get what im saying ?

i thought we were talking about a sleeved block, not stock cylinder walls. i would say that a open deck honda motor sleeves will handle about 17psi with a good cr, and a good tune. good cr meaning not something ridiculously high and not something too low, soemthing in the middle, but youll probably blow the rods before that anyways.

no i havent made any high psi, high compression honda motors, and why because i wouldnt be stupid enough to run high compression and high boost on a stock block. i got a good friend boosting 15psi on a d series, another friend got a b series boosting 9 psi. on a stock block it might be better to get some kind of block guard, but on a sleeved motor it is totally unecessary, maybe unless you plan on running more then 40psi. alot of it is on the tune, you can run 12psi on a stock block with a hack but i wouldnt expect it to last very long, but if you do it on a hondata fully tuned then i would think it would last. of course id never run that much boost on a stock block, but im a very conservative person

In my mind, 17 psi is way too risky. You might be able to run it, but its gonna put a lot of stress on it. Myself, i wouldn't run 17 psi on stock internals. I'm thinking 12 at tops, on an B18b motor. I guess it just comes down to ur own opinion and what you feel safe w/. I do kinda agree w/ the horsepower figure though, as a way to base it upon. Because, in this book I read all about tuning hondas they refer to what u need to do based upon horsepower, but then again its also an N/A book too. They say the honda blocks can handle about 50% increase in horsepower.

yes the stock sleeves can handle that kinda power but the thing is the stock rods will not. It all depends on your setup, your tuning and how hard you push your car.

17psi on a mitsubishi 14b turbo is not the same as 17psi on a t3/t4 so things do vary a lot. If you got a good tuner good things happen :)

first off, i gotta say, i'm not ripping anybody down, or trying to burst anyone's bubble.

i've just read through this whole thread, and it's surprising how many experts in this thread are asking some pretty noob questions elsewhere. i've come to the conclusion, everyone has some part right ideas and some part wrong ideas, and it leads me to question how many of you actually have turbo setups and how many of you are just regurgitating info that you've heard elsewhere. duplox, i really think you need to get over the book or whatever it is that you're talking about, and try some real world setups, because a lot of what you're saying is right on correct, but in theory only, and not practical application for a street driven b16. has anyone ever driven a b16 with 8.0 CR pistons in it? i have. on a dragstrip, and nowhere else. it's not practical for street use to build your car up to support THAT kind of boost. it'd probably barely roll on the street, unless you're drag launching at 6K at every stoplight. specific to the CR question, vtec92civic is pretty much right. if you look at just about EVERY manufacturer of aftermarket pistons, the CR's on turbo STREET DRIVEN b16's pretty much range from about 9.0:1 - 9.5:1. there's no reason to go below that. in theory, yes, with lower compression you can add more boost, but why? lower boost with a slightly higher compression ratio is ALWAYS preferable for driveability's sake, especially when you can extract the same horsepower numbers that way. also, where do you live? because that's a emissions nightmare waiting to happen. do you have any idea what kind of ticket you're talking about if you happen to get pulled over driving this thing?

i'm sure we all think it'd be a dream to drive a 550 hp CRX on the street, but the reality is, there are probably only a handful of tuners that can make that happen in the entire world, and more than half of them are in japan. i'm not saying you can't build it to that kind of power, but make it easily street driveable isn't really realistic in most towns, or necessary for that matter. 300 HP in a CRX will pretty much dust off just about anything rolling around.

also, look at the other things you've gotta get. cause you might be thinking 7 or 8K for a motor build up and a turbo kit, but you're going to need WAY more than that. you're going to have to go with a programmable stand alone fuel management system, so you're looking at another grand there, plus tuning. a new racing clutch, and for sure an LSD are going to be necessary to put that power down, not to mention suspension. good LSD's alone (KAAZ, quaife, etc.) cost a grand not including installation, and you can't just go get some one-off stage II clutch either. you're talking about at least a solid twin plate job (do you have any idea how much bigger your left calf will be than your right after a couple of months?) as for suspension, a set of skunk2 coilovers or droptech springs aren't going to do the job. you're looking at a fully adjustable set of coilovers with some pretty stiff springs, for the tuning range that you need to make even 3/4's of that power stick. then there's the ignition system, which will also need to be replaced and a good solid set of enjo or comparable driveshafts which will also be in excess of a grand. i've seen no mention of a boost controller (obviously a good electronic one like a blitz sbc-id, or HKS EVC.) that's another 500 minimum pretty much. when all is said and done, including labor, you're looking at a price in excess of 15G's to get your car up to the 550 HP level, and perform reliably, if not harshly.

like i said man, i'm not trashing anyone's post, i'm just trying to keep it real. you've got a bunch of guys here who all for the most part, have some knowledge to share, arguing over little points, while losing sight of the big picture. don't get me wrong, i think it's cool that you're looking for maximum performance out of your b16, but do yourself a favor, and this is the best advice i can give. try and find a guy with a turbo b16 CRX that has about 250-275 WHP, and ask him really nicely if you can drive that first. i'd find it really hard to believe if you came back and were like, "yeah that was fun, but i want more." my cousin has a 285 WHP CRX, and his hair practically catches on fire when he drives it. unless you're building it break some landspeed records nowhere but the dragstrip, then that should be plenty.

I understand. I just want to say that I can only base what I say in here on theory, since I don't have a Honda and never will. I drive a '69 Mustang, so things like "lack of low end power" and "emissions" aren't in my vocabulary.
I guess I'll stop posting around here, there arent many v8 turbo boards around, but I'll survive.
"i'm sure we all think it'd be a dream to drive a 550 hp CRX on the street"
Exactly why I will never own a Honda. My old motor put out that on stock bottom end (cast pistons, stock rods/crank), 8psi and revving to 6 grand. Rebuilding the motor now w/ forged slugs, prepped rod, main girdle, filled block, etc etc etc and hoping to run 15psi and 6500-7krpm. Don't think my tranny will take it though.
As for the 275hp being enough, yes it is. I build my motors because I love to do so, I love building an engine and goin to the dyno or strip and putting down some good numbers, then turning down the boost and driving home.
The whole thing about prepping your car to take 550hp is another reason I'll never own a Honda(or almost any Japanese car for that matter.. supra and an rx7/rx8 would be the only ones I can think of).. Hell this will be the second time I've rebuilt my motor, and including buying the car and the new motor I wont even be at 15k yet. When I get it painted I'll probably go over. All I have to do to withstand 550hp is throw a spool in the rear($200), a set of caltracs($350), weld in some subframe connectors($100) and maybe a new driveshaft($300). Thats just under a grand!

i understand what you're saying man, and like i said, i'm not trying to trash anyone's posts, or discourage anyone from posting here either. your ride sounds dope, and had i known that you weren't a honda guy, i probably wouldn't have said to go try some real world setups either. i'm just speaking from experience. hope i didn't offend you man.

<----has a question for duplox.....is it safe to cut 93 octane gas with toluene...Im sure the EPA wouldnt like it but from my cars point of view....would toluene be a safe substitute vs. octane booster