frankeinstien lsvtec

[looking4_12s_run]

Ok, I got a honda civic cx hatchback (not that it matters too much) and I'm aiming to eventualy get a 12 second run out of it.

I've already bought a B18C (Integra type R) head and had it ported and polished.
I've also bought an ls bottom, hence the frankeinstien.
Now I dont plan on adding turbo any time soon.

Question 1:
I want to safely get 240 HP out of this block. What do I have to do?

Question 2:
When joining the lx with the type r head, compression becomes higher (i think). Do I have to buy crower rods and valve train.

Question 3:
What are my transmission options for an application like this.

Thanx, in advance for all who respond.

[Jeff C]

So are you going to be adding a turbo to this 240hp pre-turbo block?
Would you want to spray nitrous to achieve the 240hp goal, or do you want it naturally?

[darkerdayz]

Originally Posted by looking4_12s_run

Ok, I got a honda civic cx hatchback (not that it matters too much) and I'm aiming to eventualy get a 12 second run out of it.

I've already bought a B18C (Integra type R) head and had it ported and polished.
I've also bought an ls bottom, hence the frankeinstien.
Now I dont plan on adding turbo any time soon.

Question 1:
I want to safely get 240 HP out of this block. What do I have to do?

Question 2:
When joining the lx with the type r head, compression becomes higher (i think). Do I have to buy crower rods and valve train.

Question 3:
What are my transmission options for an application like this.

Thanx, in advance for all who respond.

just wondering, how did you happen to get your hands on a ITR head? how much did it cost you? how much was the port and polish? i'm just wondering because i plan on doing a crvtec eventually and i have heard that the ITR head is one of the best heads to use.

[HondaIntegraXSI]

If it was all that great, Honda would have done it in the first place. Submitted for your approval, my thesis on why LS/VTEC is a bad idea.

What is LS/VTEC?
Why would Honda do that?
What is R/S?
Why a low R/S is bad for reliability
What is power, exactly, and how do Hondas make it?
B Series, by the numbers
How VTEC works, and why it lives at high RPMs
Why it doesn't all fit together


What is LS/VTEC?


A quick tutorial for anyone who doesn't already know.

LS/VTEC is using a B18A or B18B block (referred to as an LS block, even though it was found in the RS, LS, and GS) and mating it with any of the DOHC VTEC heads- the B16A, B17A, or B18C. The principle is to use the larger displacement of the LS block (READ: higher torque) and mate it with the high end power of VTEC. I'm also sure you've heard of CR-VTEC, which is a very similar idea. It uses the B20Z block of the CR-V (NOT the B20A of the Prelude Si, for reasons that will become obvious later) to achieve the same effect, only on a grander scale. What you end up with is an engine commonly referred to as a "Frankenstein" setup, and it's all the rage these days.


Why would Honda do that?


So why in the world would Honda put us in such a situation- having to build these incredible motors all by ourselves? Why would they knowingly decrease displacement and torque in a car being manufactured to be faster than its lower-trimmed breathen?

Look at it, too, from a manufacturing standpoint- Honda is already making the higher displacement B18A and B blocks (blocks are identical, only difference was in the head), so why go to the extra time and expense of developing and manufacturing a separate block, especially if it will decrease output?

The answer is easy: R/S.


What is R/S?


R/S is the abbreviation for rod to stroke ratio. It is the ratio of the length of the connecting rod to the length of the piston stroke, or the distance the piston travels from the top to the bottom of its stroke. As the ratio gets lower, the amount of stress on engine internals increases exponentially, killing long-term reliability. The higher the number is, the slower the piston is traveling, killing power output.

The ideal R/S is 1.75:1 (Three cheers for the B16A, at a near-perfect 1.74:1!).


Why a low R/S is bad for reliability


A low R/S means the rod will be closer to a horizontal angle on its upstroke. This means that more of its force will be pushing the piston horizontally, rather than vertically. What does this mean for your engine? Two things.

1. There will be more stress on the sides and in the center of the rod, rather than on its ends, leaving the rod more vulnerable to breaking. Picture a straw. This is no special straw, just an ordinary drinking straw. Is it going to be easier to bend this straw by applying pressure onto its ends, or at its center? Now think of your poor connecting rods.

2. There will be more stress on your cylinder walls. Once again, the rod is pushing the piston at a more horizontal angle- right into your cylinder walls, rather than up and through them. The risk here is double: A. Putting that piston right through the cylinder wall. B. The cylinder wall will actually flex under the pressure, causing the shape to turn from a circle to an oval or oblong shape. This causes the loss of the seal created by the piston rings. What happens? A small amount of oil could slip past into the combustion chamber. Bad things happen from here: The oil gets combusted, leaving nasty carbon deposits in your combustion chamber and exhaust ports- not a good thing for flow or valve sealing.

It's also important to note that as the RPMs increase, so does the amount of stress on your engine's internals.


What is power, exactly, and how do Hondas make it?

Warning: Once you see this, you will never look at horsepower and torque readings the same again, especially after you think about it.

P= (TR)/5252

P= power, in horsepower
T= torque, measured in lb/ft
R= Engine speed, in RPMs

Therefore:

Horsepower= (torque x RPMs) / 5252

Try it- pull out a dyno and see what you get.

So from this, we can conclude that if we increase torque or engine speed, we will get more power, right?

Remember that, it's important...

Now how do Hondas make power? Our tiny little 1.6-1.8L engines aren't exactly oozing spare displacement and creating gobs of torque, are they? Hondas make power through revving, and revving high. So why does everyone place so much emphasis on creating torque? It's because all these bolt-ons you see advertised won't raise your redline, but they will increase torque. There's nothing wrong with squeezing every last ounce of torque out of your engine- you should. But trying to get torque from more displacement in a Honda is like trying to fill a swimming pool using a squirt gun. You'll never get enough for it to be useful.


B Series, by the numbers


Let's take a closer look at the B series engine blocks.

In the B18 blocks, Honda increases displacement by using a larger crank and increasing stroke (the B20Z also has a slightly larger bore, which is bad for reasons I won't go into here). This, of course, lowers the R/S, since the rod length remains (almost) the same.

B16A:
Rod length: 134 mm
Stroke: 77 mm
R/S: 1.74:1
Displacement: 1587.12 cc

B17A:
rod length: 131.87 mm
Stroke: 81.4 mm
R/S: 1.62:1
Displacement: 1677.81 cc

B18A-B:
Rod length: 137mm
Stroke: 89mm
R/S: 1.54:1
Displacement: 1834.47 cc

B18C:
Rod length: 137.9 mm
Stroke: 87.2 mm
R/S: 1.58:1
Displacement: 1797.36 cc

B20A (Older Prelude Si)
Rod length: 141.7-142.75 mm
Stroke: 95 mm
R/S: 1.49-1.50:1
Displacement: 1958.14-2056.03 cc

Now you see two things: Why Honda decreased the displacement from the B18A-B to the B18C, and why the B20A is widely regarded as a not-so-great engine. Honda decreased the displacement in the B18C by decreasing the stroke, improving the R/S. This allows the B18C to rev higher, and (Hey!) increase output.

Making sense? I bet you can see where this is going. But wait, there's plenty more...


How VTEC works, and why it lives at high RPMs


A quick crash course for anyone unfamiliar with VTEC:

VTEC stands for Variable Valve Timing and Electronic Lift Control. The premise is that at low RPMs and at idle, a less aggressive cam grind is necessary to prevent "loping." Ever hear a pro drag car staging up at the gates? Sounds like it's about to stall. It's because he's running aggressive camshafts, and since the cam is spinning more slowly at idle, the intake valve is still open after combustion has completed. That's what causes loping. At higher RPMs, a more aggressive grind is desirable. The idea is that you want to cram as much air and fuel mixture (A/F) into that combustion chamber as possible, so that when it's ignited you get as grandiose an explosion as possible. So what is good at low RPMs is bad for high RPMs. So what do you do?

If you're Honda, you invent VTEC. What VTEC does is simply to employ different cam grinds at different RPMs. A less aggressive grind at low RPMs for a smooth idle and low to mid range power, and a more aggressive grind up high to produce that high end pop. At a strategically placed "VTEC crossover point," the camshaft switches grind from the less aggressive to the more aggressive.

What determines this point? Hours and hours dyno testing and tuning. If it is set too low, the more aggressive grind will kick in early, bogging down the engine (think "loping" at 3500 RPM). Too high, and the engine is missing out on valuable time it could be spending with the VTEC engaged. So all those fools who spent on a VTEC timer running stock camshafts just so they could get their VTEC to kick in earlier- they're idiots. They just cost themselves a ton of midrange power. The stock crossover point is optimized for stock camshafts.

So when is a VTEC timer necessary? Easy- when you're no longer running stock camshafts.

If you want big power all motor, you go with one of the big players in the cam game- Toda Spec B and C, or Jun Stage 2 and 3, and you accept no substitutes. All (or at least 95%) of the 225+ all motor whp B18s are running these camshafts.

How does this relate to VTEC crossover point? Well, the VTEC grinds on these cams are so aggressive, that the VTEC point needs to be moved up- way up- usually to 6500-7000 RPM. These cams will also make power to 9500+ RPM (READ: Built motor). Run these in conjunction with high compression pistons (at least 10.5:1), and you'll have yourself an all motor wonder. And this, friends, is where torque in Hondas comes from.

Why it doesn't all fit together
So here's what we've learned:


The LS/VTEC suffers from a bad R/S, due to the fact that it utilizes an LS block with a R/S of 1.54:1.
A bad R/S is bad for the engine, especially at high RPMs
Hondas make power through revving, and high power through revving higher, high compression, and aggressive camshafts

Because of its R/S ratio, it is not recommended that you rev an LS/VTEC past 6750 RPM on stock internals- the redline of a stock B18A-B. With a fairly built bottom end, it is still not recommended that you rev an LS/VTEC past 7800 RPM.

As we just discussed, in order to get any considerable power out of an engine, aggressive camshafts are a must. In order to get any benefit from aggressive camshafts, the ability to rev the engine high is a necessity. What good is VTEC if you can only use it for the top 1000 RPM of your powerband?

LS/VTEC is a fad, and I predict that it will be all but a pleasant memory in a few short years. As soon as kids start snapping rods and putting pistons through cylider walls, they'll realize how important good engine geometry is. Add that to the fact that they're running stock cams (because it's all their engine can safely handle) and getting burned by kids running Todas, or Juns, and they'll wish they had just stuck with their trusty B18C. Like I said, if it was all that great, Honda would have done it in the first place."

[Ricochet]

Question 1:
I want to safely get 240 HP out of this block. What do I have to do?

Well you'll already have about 180, and an i/h/e will add probably another 20 with that high-flowing setup, so there's about 200hp. I'm assuming you have an itr intake manifold, but if not get a skunk2 or eidelbach (sp?) one with a 65mm+ bore.

Question 2:
When joining the lx with the type r head, compression becomes higher (i think). Do I have to buy crower rods and valve train.

I'm a bit shakey on this one so somebody correct me if I'm wrong, but your compression should still be the same as an LX if your using its gasket and pistons. A nice set of rods and higher compression pistons will definitly help with power since you have a p/p itr head, which was made stock for 11.1:1 compression. You could even raise it well past that, but shouldn't unless you feel like buying hi-octane (non-pump) gas the rest of your engine's life.

Question 3:
What are my transmission options for an application like this.

If you raise your compression with upgraded internals you'll basically have an itr engine with a lot more torque, so I would say buy an itr tranny, or ctr if you can't find one. But with LX internals, I don't think you should rev up to the itr's 8400 redline because of their weaker r/s ratio. BTW what ECU are you using?

For your car to hit 12's, you're going to need a lot more than 240hp btw.. more like 300-400. Good luck hitting those numbers without forced induction.

[Ricochet]

XSI, that was a wonderful rainbow if information, but he's asking how to make his setup better, not whether it was a good decision or not. Cams will help bigtime, I did forget that part, but driving/idling on the street will be kinda rough. Also, he's upgrading his internals so reliability will greatly increase.

Oh, one more thing... I didn't think the B16A had a r/s of 1.74, I thought only the B16B did. I'm unsure about that, but do they share the same crankshaft and rods? I know the B has forged pistions and the A doesn't.. Is that a variable in the r/s? Again, great info, but try to be a bit more constructive.

[darkerdayz]

also, XI, i noticed that you didnt put the R/S ratio for the b20b/z. if you looked it up, you would realize that it is also near perfect.

[looking4_12s_run]

All right. So I havent been around to talk much, but I'm back.

Let me correct something before I go any further. I appoligize for the mixup. I dont have a LS bottom, I have an RS bottom.

As for internals.
Ive got civic type R pistons already and Im going to get a full crower valve train and rods for the sake of durability.

Someone asked how much I picked up my head for. I got it already ported and polished (very nicely too) for $2000(CAN). Yes, its a bit much, but you try finding one of those in montreal for cheaper. After selling of the ITR bottom for $600 it became a reasonable purchase. The RS bottom cost me $400 and Im still searching for a transmission. I was hoping to pick up the Civic Type R with LSD but I cant find a good deal on one.

Im told my compression should be in the 11:1's so Im thinking that (as someone else already mentioned) Ill be getting about 200 hp out of it.

I already have a ITR intake manifold so I wasnt looking to get the skunk2 yet. However, I dont have a the VTEC computer yet, so if you can tell me which one will give me the most bang for my buck, it would be appreciated.

I think you guys are all very helpfull and I thank you all but Im still needing to get an extra 40 hp out of this car.

:: to think this all started with a stupid bet. Some fuck told me a civic could never have 240 hp. Grrrrr. I'm on a limited budget but with your help I'm sure to succeed ::

[edman24]

ok cool info in this thread but all stuff that has been said many times over. first off lsvtec is not a bad idea. i had it for a while and so do quite a few of my friends with absolutely no problems. let me teach you something. you said the b18c has what r/s ratio? 1.58:1? thats not great in my opinion, and when compared to lsvtec swaps its not very much worse. and nobody said anything about the b20a motor. the only good thing to come out of that was the crank but thats a side note. hes talking about either the b20b or b20z which came in the crv. the b20a would never work in a civic without serious engine mount reconfiguration.

now back to r/s ratio. im so sick and tired of people using this as a reason why lsvtec is bad. how many engine out there do you think have r/s ratios any better then an ls motor? not many at all. yah the b16 is good woohoo so i can rev to 11000rpm and you cant, big friggin deal. while youre getting there ill be halfway down the track with gobs of torque so whats your point? torque wins dragraces, not hp.

it is very possible to pull 240hp all motor out of this setup. but it will be a little more difficult considering you are keeping it a 1.8liter. you will definitely need higher compression then ctr pistons will give you thats for sure. and youd need like jun stage 3 cams with some good tuning but its very possible. in fact jun has their own gsr with 240hp all motor on their website im pretty sure and its in the 12's.

so heres the setup:
b18c5 head
jun stage 3
HD valve springs
heavy port and polish
b18b/a block
je 12-12.5:1 comp pistons
crower rods
block guard
EG civic cx
CTR or ITR tranny WITH LSD!!!!

very possible in the 12's if you do it right. might not be great daily driver cause youll need race gas and it will idle like crap but it will get the job done and do it well.

[93civic$racer]

wow, im pretty surprised on how skeptical everyone is....we are talking about a frankenstein motor in a hatch with a p/p ctr head and a overhualed rs bottom end...which means you can rev ur motor to around 9k(i wouldnt do it too much) and if u are trying to go all out u can even stroke the bottom end....but lets say u dont have money to stroke the motor....with stage 3 jun cams and high compression pistons and all the neccassary bolt ons you should be getting into 12's without having to be in the 300-375 hp range.

[HondaIntegraXSI]

Q: Oh, one more thing... I didn't think the B16A had a r/s of 1.74, I thought only the B16B did. I'm unsure about that, but do they share the same crankshaft and rods? I know the B has forged pistions and the A doesn't.. ----- A:The cranck and the rods are the same therefore it is the same R/S, but the pistons are diff so the comp in the B16B will be higher and the forged pistons are made to endure more heat therefore increasing it's reliability ant high rpm's..

[HondaIntegraXSI]

The B18A/B is a peice when it gets past 7K, ask and reliable shop that knows about hondas. If you want a 1.8 with a B16 head, do it right, get a stroker kit... if you want torque, go with something other than honda, If you want a 2.0, get spoon to make you a stroker for the B16A/B ore the B18C1-5(inc. 2 3 and 4), curently I got spoon to custom make me a 2.1 stroker(closest you will get to torque w/ a honda w/o boosting it) for my 500,000km XSi.Don't get me wrong, but a frank motor is a bad Idea for the daily driven application, but is hot as hell for the track.and the little comment about you halfway down the track before I hit 11k is dumb. think about it, If you have to shift while I'm pulling wouldn't you shift and fall back about a carleingth from you previous position on me. I do't have to shift once for the whole 1/8 mile, and can ride 2nd out in the 1/4 on a stock tranny, but I have spoon gears on 1-4 and a stock 5th so, you make the call.

[Ricochet]

I've only seen 1.8 stroker kits from Spoon, but I'm sure they can custom build a 2.0
http://inlinefour.com/spoon18lstro.html

JUN has one as well
http://inlinefour.com/junb16a16to1.html

[93civic$racer]

think about it like this torque x rpm = hp....if you have a car thats able to reach high rpm but doesnt have the torque you a situation like 4(implamenting rpms) x 2(implamenting torque) = 8 then you have a situtaion were you have a car that has a more balance between torque and rpm like 3 x 3 =9 so imo the balance between torque and high reving is were u get the speed to shoot ur ass down the 1/4. just an example.

[HondaIntegraXSI]

if you are going to have the same numbers in motor power then yea, but the one that holds less rpms has to shift more often, therefore losing the race.(even though it has the same power fiqures). yes spoon can build custom. they are making me a 2.1L kit for a B18C3-5 and customizing it for the B16A first gen. it's as pricy as the Jun, but it's 2.1L instead of 1.8L. I have spoon gears, ECU, Camshafts, valvesprings& retainers, clutch, flywheel, and driveshafts, an hasport cable to hydo conversion, $1000 buck p&p job and a ITR LSD with about 50 hours on the dyno. the extra displ;acement will help a lot, but it will drop safe RPM's to 10,500. Even though spoon makes a good kit, I will still get it balanced and polished some more, shoot and peen the beams and mill the head .005 inches then I will have about a 10.9:1 comp ratio.