preludeSI94

I just bought a 94 prelude si and im going to build it up all motor.
I was wondering if anybody's heard anything good about Gude head packages?
And also i'm thinking about JDM type S pistons...if not what pistons are good?
Thanks.

PikkaGTR

congrats on the buy
welcome to HAN man, hope you enjoy ur stay here
if you do get the type S pistons make sure you get the cams as well
works great together

preludeSI94

type s cams wont work in the h23 will they?

rti92si

I tried to find out the same thing but all i could muster up was a maybe...i don't think it will work because of the H23's increased stroke, I believe the higher compression dome on the type-s pistons will hit the valves if used in our H23's. Gude seems to be an excellent company I wanted to get their head package to, but instead of type-s pistons you could use something from JE, Arias, or any other reputable company.

hope that helps
Andrew

preludeSI94

Thanks for the reply andrew
i know on the gude head package they shave the head quite a bit, enough to raise compression about a full point so around what compression piston do you think would be good? im guessing like 10:1 or so...I know with a mildly ported and shaved head the type-s piston fits in the h23 but im a little worried about it with the gude head

rti92si

Well if it helps any our motors stock have about 9.5:1 compression (9.6:1 Im pretty sure), so if the head raises the compression a full point which is a fairly big jump your looking at 10.5-10.6:1 which is around the H22's I believe. So nothing higher than 10-10.5:1 or else you will be going pretty high and need a good tune (a good idea regardless) We already are supposed to run 93 octane on our H23's same with H22's so I think 10:1 pistons (which would then be increased to 11:1) would be great...but remember not all gas is created equal if you live in an area that has poor gas (California comes to mind) you may not wanna do it as their production cars have a hard time running optimally on their gas (The 350Z with cams and other bolt on parts from Nismo nets nearly no horsepower gains in CA as the computer cannot send any more fuel as detonation will occur with that crap gas. Just check out the magazines complaining about their test cars using CA gas if they are based there.)

Sorry that was so long but thought it might help you out. As GA where I live has pretty good gas, but the past few months a few random tanks have been awful and my car has sputtered, stalled, popped, and wheezed because of it. If that happened with 11:1 compression it may result in more serious problems unless the computer can put it in a "limp home" mose or something.

Sorry for the long wind :-)
Andrew

preludeSI94

thanks again for the reply
I live in iowa and the gas here is pretty decent and i want to build something that will have pretty high compression so i might try to go with like 11.5:1 if i can. what 1/4 times should i be hoping for with all motor in an h23? im thinking somehwere in the 13's maybe but im not sure.

HeavyFooted

How many miles are on your h23?

rti92si

Well I know the head package adds about 75bhp so with the compression increase and the prerequisite bolt on's you should be seeing about 250bhp maybe closer to 300bhp but no more. Basically you'd have I/H/E/Head/Cams/HeadWork/ECU...so heres the math:

(All Flywheel numbers)
Baseline-160
HeadPackage- +75 = 235
I/H/E- +30ish = 265
With appropriate tuning you could see higher gains.

For anybody questioning my bench dynoing:-) You have to understand the Head Package from Gude as it is cams, headwork, valvetrain upgrade, valve grind, porting etc. in one package. Thats how the one item adds that much power as it's a combination of a lot of work listed as one whole deal.

So assuming everything is tuned correctly and you upgrade the suspension, tires, and drivetrain accordingly you could probably dip into the high 13's as long as you drop some weight of the car (ie- remove sound deadening, carbon fiber hood/trunk lid/sunroof etc.) But remeber 13's are pretty fast for a fwd car like ours...I've seen LS1 Camaro's run in the mid to high 13's with exhaust/intake at the track with not so great drivers and stock tires...and those are rwd cars designed for that purpose.

For comparison, the E36 style BMW M3 runs in the low 14's high 13's stock and it has 240bhp, however the gearing is much more aggresive and it has a significant traction advantage because of the amazing suspension setup and rear wheel drive. You would need to modify the suspension in order to let your front wheels put all that power down as best as possible or else you wouldnt run as fast you'd hope or think...but regardless from a roll your car would be quick. From a stop however you would be at a distinct disadvantage as fwd is not ideal for drag racing.

Umm...I hope all that made sense? lol.

rti92si

To simplify...watch some videos of fast hondas like eg civics or what not racing supras, camaro's, etc. Most of the time the RWD vehicle takes the FWD off the line regardless of the power the FWD makes, as RWD = better traction/weight transfer, but as speeds increase the Honda's will pass because of superior power to weight ratio. Thats why most of the videos of the beast Hatchback Civic's are on the highway where the traction advantage of RWD is not so much of an issue (that and you can go faster on the highway of course)

So you may not hit 13's but your car will sure to be quick from a roll and definately on the highway.