compression ratio help
 

alright i have been serching this, but i'm still indecisive. my power goal is a stong 200+whp on stock internals. should i lower my c/r to 8.5 - 8.9:1 (stock is like 9.1390:1)? that way i can run more boost without knocking and have good reliability. i am not to worried about spool time because with my manifold, and how small my turbo is, it should hit full boost really quick. so i will not be out of boost for very long. i will be using a front mount intercooler. and my turbo is the WRX TD04l 13T. and i figure i will have to run like 13-14 lbs. (maxing it out) of boost to make that power goal. what do you guys think?

Re: compression ratio help
 

It would help to know what engine you have...

Re: compression ratio help
 

crap i knew i forgot something. it is a D16Z6 with 60k on it

Re: compression ratio help
 

You dont need to lower compression to hit that # and be reliable, but vitaras are cheap and would lower the static comp. ratio anyway, if your dead set on cracking your motor open.

Either way works. Tuning is still going to make or break it on any turbo build.

I think there are some stickys for you to read also.

Re: compression ratio help
 

wow sorry i didn't realy look in there. i first looked a long time ago when i first joined there has been alot added. but the only problem is if i do the vitaras i have to rebalance my crank (to do it the right way).

Re: compression ratio help
 

If you're only shooting right around 200 whp you'll be fine with your setup. Like Hitchhikkr said, it really boils down to how well it's tuned... ----, you can turbo a car with 11.0:1 compression... you just have to have a good tune.

Re: compression ratio help
 

https://www.homemadeturbo.com/forum/...?topic=97232.0

Vitaras are super cheap and can take a good amount of boost on pump gas.

Re: compression ratio help
 

why would you rebalance the crank? your not doing anything to it....i could see weighing all the pistons to makes sure they're all the same

Re: compression ratio help
 

i guess i assumed that the vitaras weighed more. but i guess i should check and see the weight specs, and if they are the same or realllllllyy close then i would not need to rebalance the crank. but is it even worth it to put vitaras on stock rods ( i doubt i will find better rods that weigh the same as stock). because it would be alot easyer to just get an oversized headgasket since the head is already off.

Re: compression ratio help
 

Man I wouldent even mess running vits. I would just stick with running the stock ----, and get some arp head studs, and call it a day.

Re: compression ratio help
 

stock c/r too?

Re: compression ratio help
 

vitaras are very light

Re: compression ratio help
 

Stock D16Z6 are known reliable at 225-240 whp. I think they are good for more, but people need to be more sensitive to heat soak since it's a small bore engine.

Re: compression ratio help
 

alright so i decided to just get a bigger head gasket since i have to get a new head gasket anyway. what c/r do you guys think i should run? and i am also getting arp head studs.

Re: compression ratio help
 

If you do vitaras, get some rods. The stock rods are the weak point.

However for your goals you don't need to open the motor if it's healthy(why do you need a hg?). Here is one example of how far a stock z6 can go:

http://www.honda-tech.com/zerothread?id=2104408

Look on page 11...

Re: compression ratio help
 

i need a new head gasket because the owner of the engine had taken the head off already.

Re: compression ratio help
 

well im rocking a stock d16z6 botom end, with 180k miles on it. Im boostin 9psi, on a garrett t3to4e 50 trim, and im sure im over 200hp.

not going to go dyno a winter beater set up but, id bet iv cleared 200hp.. i do have a built head, cams and skunk 2 IM..

Re: compression ratio help
 

Honda OEM head gasket.

Re: compression ratio help
 

D16Y8 headgasket is the cheapest, from the dealer, and fits right on.

Re: compression ratio help
 

You definitely are over 200whp. My friend lifted his head on a stock d16y8 at 9psi. Ebay t3/t4, nice manifold, and a dyno tune. He made 250whp.
Im about to boost my second del sol that has it's original z6 with 175k miles.