B20B turbo

Ok ok I have used the search button on this forum way too much reading about crvtec and how unreliable it is (or could be).I am in the same problem as many people are in deciding which one to put in my 96 civic cx a b20/vtec or a B18c1. A B18c1 is running $3300 and it doesn't seem to be going down anytime soon. A B20b longblock right now is $799. Now I've read most peoples arguements on putting a vtec head on this block and how it is much more then tapping a hole, and slapping a different head on it. I've also read some people saying forget the head and put a turbo on. From what I understand the b20 was never meant to rev to 8,000 much less repeatedly so with a turbo where most power comes on at 3-4,000 it would be easier on the engine. I know it would need to still be reinforced such as pistons, rods ,etc. I don't have a problem in spending money on a engine if its meant to get either more power or reliabilty. So the question is what kind of turbo set up would I need to get a b20/turbo going? Feel free to argue more about a B18c is better then either. :p

t3/04 for balls to the walls

I agree w/ CivSiGuy.
If you put on a turbo its not worth to get teh VTec head, too much money and hassle. I would rather see that money put into PnP and some valvetrain upgrade, and turbo cams.
Also get the LS trans if you're going turbo, it has longer gears and get a LSD for it too.

Originally posted by kane2g
I agree w/ CivSiGuy.
If you put on a turbo its not worth to get teh VTec head, too much money and hassle. I would rather see that money put into PnP and some valvetrain upgrade, and turbo cams.
Also get the LS trans if you're going turbo, it has longer gears and get a LSD for it too.


I agree 100% with Kane

i have often thought of just using the b20 block. i'm not up on the b-20. i assume it is twin cam since it is a b series block correct? I am intrigued by turbo. i like the thought of snail power. but i also like all motor. the b20z is the motor to have to all motor correct? would the b20 accept things such as type R cams and intake? I am all about budget power and getting the most bang for the buck. and, like a lot of people i am a little scared by frankenstein engines. so anyone with lots of knowledge on the b20 feel free to chime in

Originally posted by CivSiGuy
t3/04 for balls to the walls
ball bearing turbo... The bestest $2000 investment in a car! :devil:

Well i wasn't thinking of doing a b20/vtec/turbo at all. It would either be b20/vtec or b20/turbo. I like the turbo idea a little more because I don't hear too much about it, plus the sound of a bypass valve gets me a little excited:D . Now also where would I go about getting a lsd for the ls tranny? I assume its a third party because none of the integras came with lsd (maybe type r but its in a class of its own). It seems from a lot of post that I read that a turbo would be a little easier on the engine then a vtec head would be considering it doesn't need to be redlined to get power.

white97ex:
you could bolt all that stuff on , if you put on a vtec head.
h82lose:
I think that the b20turbo would destory all moded type-Rs. You could hang w/ 5.0 and z28.
The LSD of choice is Quailfe. I think that groupbuy has a deal on it.
Also you're right about turbo, raising RPM limit 1000RPMs will put more stress on the engine than running 10psi of boost. Do you see why turbo is better?

keep in mind if you do get a b20 on boost, you will need to spend some $$ on suspension and good tires, if you haven't already have done it.

i realized what i said on my way to work...of course type r cams wouldn't work on the b20 head its not vtec..hehehe......is the b20 DOHC though.

sorry for the double post but does anyone have HP and torque numbers for the b20?

I suggested this a while back, but didn't get much response on this board - if you do it, go with an LS tranny, manifold, and ecu. A JDM b20b has 140HP and I forget the torque numbers. Seeing as it gets 22-25mpg in a huge SUV, and is built to pull all that weight, if you put it in a light-ass civic, it'll be putting more HP to the ground than an integra LS does, plus you'll be getting good gas mileage, too. That's without the turbo.

ok how about this.......lets say you dont want to mess with the cr/vtec. what about an ls head so you dont have to worry about the hood clearance/intake problem? is this a possibility. I am looking for economic and reliable power. and i either want to go all motor or t/c.

It's not the had that needs clearance - it's the same head an LS has. It's the intake manifold. All you have to do is put an LS intake manifold on it, and it'll work.

I've been looking for turbo kits or any kind of information on how to turbo a b20 and this is what I've found. First you take a b20b and switch the manifold with a ls manifold(b18b) because it won't allow you to close your hood. Then you could take a Fmax turbo kit for the b18b for about $3799.99 and turbo it. The fmax kit comes with everything except from what I can see a good ecu. So am I right though in assuming that any b18 turbo lit will work on a b20? Any other suggestions? Oh one more question, a b18b produces 142 hp and 127 torque right? A b20b produces about 126 hp and 133 torque am I missing something. I thought it produced more then that. I know a b20z makes like 146 hp and 133 torque but thats because the compression ratio is higher. Whats up?

for the intake you could go w/ LS one or you might as well get a Skunk2 one which can be found for about 200. As for the ECU i would recomend a Hondata system, they got some good stuff.

ok could someone give me an approx hp/tq number on this?

b20z
ls intake
je high comp pistons about 10.5:1
full exhaust system
CAI
......i've drawn a blank. im trying to lay out an all motor set up. anyone got ideas.

ok now lets compare prices. anyone know the cost of a properly executed cr/vtec motor?
if you turbo a b20 without head swapping your looking at around 4 or 5 grand
all motor probably 2500 to 4000
not including installation of course........those numbers sound right... what kind of hp/tq numbers are we looking at, stock cr/vtec (no mods i know its not stock), b20 all motor, and b20 turbo.

h82lose, if you get the JDM b20b from hondamotorsonline.com, it (like all other JDM b20bs) have 140hp.

So a jdm b20b gets 140 hp. What are its torque numbers? Any one know why its different then the USDM? I know usually jdm motors generate more power then USDMs do but why. Only thing I can think of is compression.

Originally posted by h82lose
So a jdm b20b gets 140 hp. What are its torque numbers? Any one know why its different then the USDM? I know usually jdm motors generate more power then USDMs do but why. Only thing I can think of is compression.

first off the jdm b20b is not the b20b, it is the b20z and its almost a point higher in compression. the head flows like shit, period. the intake is the worst thing i have ever seen with runners that are a foot long if not more. and like any other 2 liter plus motor honda makes with the exception of the s2k and accord type r motors it has horrible engine geometery and yes that includes my beloved h22.

with a vtec head it will flow very very well and structurally the block is very solid. but like any other honda it wasnt designed to take boost and will eventually fail you in the 9-12 psi mark. vtec would be much easier on an engine then boost, although neither would be great unless the motor was balanced or built or both. there is no cheap way out, period. although i could say i could build a cr/vtec in my garage for about 500-even then a b20/turbo so thats your call.

So are you saying that the b20b works better with a vtec head then by turboing it?

Originally posted by h82lose
So are you saying that the b20b works better with a vtec head then by turboing it?


niether, its a frankenstein motor if you make a cr/vtec and its a naturally aspirated engine recieving boost if you turbo it. either way you go your going to have to do work to it that will eventually equal itself out. for instance.

if you want to do the cr/vtec the right way its gonna cost you a couple grand in parts and labor to make it be able to handle the higher redline and the head that wasnt meant for the block. not to mention all the initial parts like the block and the head and the tranny you will need unless you have a b series allready.

and building a solid b20 turbo will cost you maybe a little less maybe a little more depending on what you do.


if i was hell bent on putting a b20 motor in my car i would build the cr/vtec first. i mean go all out, destroked, forged pistons, rods, sleeves the whole nine yards.....

then after i got bored with that motor i would turbo it, hey its allready built right? and its got a better head then any non vtec motor.

yeah sure you could have the b20 head ported and polished and spend all that money or you could use a vtec head that flows extremeley well from the factory and has the higher redline stock. not to mention that vtec is good for turbos unlike most think. sure the valve overlap isnt the best thing in the world but a totally seperate camshaft profile to extend the heads breathing ability past a normal redline mean more workable powerband for you and your turbo.

but then again thats just what i would do.