avividmemory

ok, going with the infamous ls/vtec cuz im cheap...b18c1 head, b18b block...already turboed, but when i do the build up this winter to conver to ls/vtec which pistons should i get for approx 12-18 psi?

i know this goes back to the whole, low compression v. high compression on turbos...but what would be more beneficial power wise 9.2, 10.5 etc...

either way they'll be je pistons...and what about stock rods

this post from last week might also be tied into this discussion, cuz it talks about the effective compression formula...thanks
https://honda-tech.com/zerothread?id=313474

92JDMSiR

take a minute to think about the rods question. 12-18psi is a big difference. whether it be 12 or higher you should definitely get rods. your going to be down there anyway pullin the pistons out. 98% of the people on this board are going to tell you to run something like 9:1 compression. 9:1 is a good compression ratio to go with but persoanlly I like higher compression with really good tuning. the lower the compression the more forgiving the motor is for boost. if you know somebody that is good at tuning with a standalone then higher cr will make more power. I don't mean like NA 12:1 but personally I would go with 10:1 and tune it like crazy.

Armed Ferret

can't use JE's (or any other aftermarket forged pistons that i know of) on stock rods......they use a floating wrist pin, and honda pins are pressed in.

crower and eagle both make a budget h-beam forged rod, for about $350 a set (give or take a few bucks).

avividmemory

yeah i wasnt sure if you could or not...eagle is what ill end up going with...

filetofit

I'm running JE pistons on stock LS rods in an LS/Vtec turbo setup right now. The stock rods and pistons have the wristpin pressed into the rod not the piston. THe wristpin floats with respect to the piston not with respect to the rod on stock setups. I'm looking at the stock pistons I took out (all the top ringlands were broken, every piston) and they have an axial oil slot in the wristpin bore. JE's have a circumferential oil groove in the wristpin bore and an oil hole that coonects the groove to the oil ring. The only trick to using JE pistons on stock rods is that the wristpins will have to be pressed into the rods. Using Eagle rods gives you a double floating design which I suppose distributes the wear between the small end rod bushing and the piston wristpin bore.

Vu

If you don't mind me asking, where will you get the oil supply to feed the VTEC head? Not from the same oil sender you used to feed the turbo, right?


[Modified by Vu, 10:08 PM 10/28/2002]

avividmemory

not from the same spot...head will most likely come from the pump in some way

Vu

So there is more than one place to get the oil supply from on the block?

X2BOARD

There is a reason good engine builders do not do this... I wouldn't recommend it even on an n/a setup. But your name is Filetofit and I can respect that ! LOL

If you are planning to run anything over 10psi, I'd highly recommend aftermarket rods anyways. and over 14 psi, I'd look at sleeving... but cost is an issue.

Something around 9:1 is great for turbo... but pushing 10:1 + boost is not good, even well tuned, the motor will not be forgiving at all, one slip up or a faulty injector and ringlands go bye bye.... If you want a nice setup, for about 15psi, you might want to run a stock LS 9.2:1 CR for boost, but remember, you have a head with combustion chamber smaller than the LS's, so you'll need to have the actual piston CR calculated.

X2

avividmemory

ive been told to tap from the hex screw on top of the oil pump with a -6 an line...

.......
so you think 9.2:1 will be all good?
i dont plan on running an excess of 10 lbs daily...i figured 14 maybe even 16 at the track for a few runs...but nothing daily

filetofit

The JE pistons are installed onto stock rods the same way stock pistons are... what's the diff?

I mean if jinxproof and co. did it it, it's good enough for me.

https://honda-tech.com/zerothread?id=167236


[Modified by filetofit, 6:51 AM 10/29/2002]