I posted a while back about a 14.5-15 NA Integra. I've got an '96 LS right now, but will be swapping the head and block out for a different set up. I'm looking at buying a B20 block out of a junk yard CRV and using an LS head. If I recall correctly I can use the crankshaft and valvetrain out of the B20 and LS respectively.

Got a few questions:
Set up will likely include a Skunk 2 Intake manifold, lightweight flywheel, porting the head, valve job, and Crower 404's with proper springs. I will be rebuilding the block personally... and I was wondering how well this set up would respond to boring the cylinders out and using higher compression pistons? Also, what about fuel delivery and tuning/management? What steps should I take to get a good system running, or can I just reuse the ECU I've got? And finally, if I recall correctly, I can get a GSR transmission and it will bolt up fine. I would assume this means I'll need to get a GSR clutch, correct?

Also, seeing as the response to my earlier thread was similar to "Dude your numbers are a little high, shoot for faster." What would it take to hit 14 or even break it with this set up? Thanks for any input guys, I'm in the process of researching this still, but those are just some glaring questions that I couldn't quite find answers to.

-DaBat

 

What kind of a rebuild do you want to do? Aftermarket rods/pistons? You don't want to bore out the block unless you get aftermarket cylinder sleeves, which is highly expensive for what you want to do and overkill. You won't need more than the 2 liters the B20 would give you. If you want higher compression, you're going to need to get aftermarket rods and pistons. I would use something like a Hondata S200 to tune the car with, and have someone experienced tune it. That setup along with a GSR tranny should probably get you near a 14 flat...it's a setup I've wanted to build for a while, never seen anyone with it before...so I can't give you any exact numbers. You can use your LS clutch with the GSR tranny, but I'd get an aftermarket clutch while you're in there replacing the flywheel.

 

Well, I was planning replacing all of the internals any way, and I see it as a waste to go with OEM, if I have the block torn apart and am spending the money on OEM parts. My question was basically how well the LS head and cams would work with the higher compression.

Yeah I was planning on getting a stronger clutch.

Would the redline on that set up be equivalent to the redline on a B20 with a B20 head??

-DaBat

 

I agree with the rebuilding with aftermarket parts instead of OEM. This will allow you to rev the motor higher than with OEM components. The LS head and cams will work well with the higher compression, just like any other motor. The redline between LS and B20 blocks are the same, because they use the same crankshaft and rods...the only difference is the bore size of the cylinder. With aftermarket rods/pistons/springs/retainers/cams you should be able to take it to 8500+ rpm.

 

too big a cam on an ls would have a lopey idle. hope you dont mind.

 

I don't think there's anything finer in life than a shitty idle.

 

What brand of internals would you suggest I look at? There aren't too many companies that make pistons and rods for this set up... at least not too many that I could find. Where would you suggest I start??


-DaBat

 

I would go with a Wiseco piston, and your choice of rod. Check out www.importbuilders.com for a test of different kinds of pistons. You're looking for an 84mm piston, and an LS length rod...they are all over the place if you know what you're looking for.

 

Not to seem like a pest, but the only 84mm pistons on Wiseco's site are either stock compression or 11.5+. Isn't that really high?

-DaBat

 

http://www.importbuilders.com/pistons.html

There's a piston listing of off the shelf pistons that importbuilders sells. Your compression ratio will be different because the compressions listed are with a VTEC head. 11.5:1 isn't really high, that's a decent NA compression ratio...you could run it on pump gas no problem. You can always order a piston with whatever compression ratio you want...they can make it.