Would stock bore CTR pistons in my b18c1, w/ everything else being stock internally, be a bad idea?? What would happen and what kind of gains might I see?

I would eventually be getting the CTR cams and the valvetrain.

Mike

 

someones gotta have some info

Mike

 

You would see a very modest power gain (between 6 to 8 hp at the most) pretty much all across the rpm band. When you raise compression, you don't alter the air/fuel ration, all you do is compress the mixture more and when the mixture ignites it moves the piston with more force due to a larger explosion. Just remember that compression alone doesn't make power, you can probably spend the money for the pistons on a CTR intake cam (the exhaust cam is very similar to a GSR cam so don't bother with it unless your power expectations are high) and see more of a power gain up top (due to the increased duration and lift). Also remember that putting in a cam takes less than an hour if you know what you're doing and putting in pistons is a weekend project for you and three friends plus the cost of getting the block honed and if your unfamiliar with engine assembly you'll probably have to pay someone to do that also. If your looking for modest power look in places other than the bottom end, however if something happens that forces you to have to rebuild the engine anyway, then I'd go ahead and replace them. Also be sure and have a goal in mind: you don't want to put high compression pistons in an engine just to decide two weeks later that you want a turbo. Whatever you do, approach your car and your modifications with a goal.

 

Thank you , great reply . i may just hold off on the piston install until I can put them in along with the cams and valvetrain and hondata.

Mike

 

also remeber that once you up your compression past a certain point you cant go the turbo route anymore.

so it would also help if you decided now, whether or not you wanna go turbo, or NA.

if you do go NA, then get i would suggest getting the complete "internal" package ( polished crank, rods, pistons and sleeves) and get a compresion ratio of 12:1 or heigher.

that way, you wont have to pop your engine again 5-8 months down the line to "upgrade" it again.

my 2 cents.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 7thGear &raquo;</TD></TR><TR><TD CLASS="quote">also remeber that once you up your compression past a certain point you cant go the turbo route anymore
my 2 cents.</TD></TR></TABLE>

I disagree. You can run a turbo on any motor you want as long as you realize that you won't be able to run as much turbo on a higher cr motor and tuning will be even more essential. According to Corky Bell, a 9.0 cr motor on 10 psi is the same thing as a 10.0cr motor on 9psi.

 

i'll agree about the small boost amount, but thats considering if hes going to stay in the small boost category

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 7thGear &raquo;</TD></TR><TR><TD CLASS="quote">i'll agree about the small boost amount, but thats considering if hes going to stay in the small boost category </TD></TR></TABLE>

Bah, don't sweat it...jump up to like 14.1 CR and run like 25 psi. It'll be fine

 

i think the car would dig its own little grave in the asphalt from an explosion like that.

 

Yeah it'll be all motor.. It's already been boosted before, but I took the turbo off to go the N/A route.

Mike

 

stock cams are designed with relatively conservative timing events, which increases what is known as the effective compression ratio.

long story short, at the minumum, you'd probably have to run premium gas on a normally aspirated motor that might have originally been designed to run 87 octane... not a good candidate for adding boost using pump gas.

go read the 12/03 issue of sport compact car to see what i mean... the turbo kit was designed to add only 6 psi of boost to a bone-stock d16, but something went wrong, and the motor was totalled on it's first test drive after installing the kit!

if you are only supposed to safely add 6 psi of boost to stock motor, what is the limit for a motor with your increased c.r.? 2 psi of boost??

if boost is in your future, you want a low static c.r.... you'll make a lot more power, and you'll do it safely.