Lower Comp Pistons...
 

I have a ZC engine that I am rebuilding, I am planning on running a turbo with 8-10 psi. Should I lower the compression to 8.5 -1 or keep it stock at 9.5 - 1???

Re:Lower Comp Pistons...
 

Not a bad idea, why don't you look into those supra piston sets that guy on honda vision was offering?

Re:Lower Comp Pistons...
 

Stick with 9.5, that is what I did on my built zc.. Endyn offers roller wave forged pistons for the ZC as well.

check it out

www.theoldone.com

Jeff

Re:Lower Comp Pistons...
 

What pistons/rods did you use Abaz?? I was looking at the site and they had 3 types listed for the ZC, NA low, high and FI.... are the NA Low going to be sufficent??? Will they beable to withstand boost??

Re:Lower Comp Pistons...
 

9.5 c/r ZC fI pistons

Jeff

Re:Lower Comp Pistons...
 

Did you have custom pistons made??? I emailed the guys at endyne and they told me that they dont have anything, they could make custom pistons but would have to sell 2 sets to make it possible. Their FI pistons only range from 8.23-8.54:1

Re:Lower Comp Pistons...
 

Now that I think about it, I think it was the low NA pistons..

Jeff

Re:Lower Comp Pistons...
 

Any guesses as to which SRP piston would yield 9.5 on a ZC?

Re:Lower Comp Pistons...
 

I noticed that there are FI 9.45:1 D16A6 pistons available, would those be able to fit into a ZC? If so is there any draw back to using those over a ZC piston? Oh ya are you using the roller wave pistons??

Re:Lower Comp Pistons...
 

So I talked to Larry today "the old one"

he stated this about those pistons..

"We reconfigured them to reduce the compression with the deep ZC chamber.
The ZC's chamber depth and it's resultant tendancy for detonation was a tuning problem for a lot of customers who were low-balling turbo set-ups. You also have to understand that most of our customers on these are not going to spend any time tuning the combination and we felt that reducing the compression was the best way to prevent some customers from damaging their engines...and blaming the people who supplied the parts.
Those who want higher compression pistons for boosted ZC applications can still buy them from us, but they need to convince me that they're planning to do some serious tuning first."

So looks like I did get his early 9.5 FI pistons when they came out about 2 years ago.

Jeff

Re:Lower Comp Pistons...
 

Hmm.... with that being said, are there any pistons you would recomend? Do I have to get pistons specific to a ZC engine or can I use pistons from another engine (ie integra)??

Re:Lower Comp Pistons...
 

Call that old fucker up and tell him you want those pistons, he will give them to you. Tell him Jeff @ homemadeturbo.com said So ;)

Yes, you have to use pistons that are specificly for the ZC. If you put a d16a6 piston in a ZC lets say thats rated at 9.1, when you put it in your zc, it would be like 7.8

as far as I know, endyn is the only people who make pistons for the zc. you may want to give J.E/SRP a call and see what they have to offer.

Jeff

Re:Lower Comp Pistons...
 

now that I think about it, if JE has a listing for D16a1 88-89 integra, those will be perfect..

Jeff

Re:Lower Comp Pistons...
 

to answer on the srp question i think they make them for a d16a6 at 8.8:1 that should be about 9.2 on a zc

Re:Lower Comp Pistons...
 

No, if you put a6 pistons in a ZC, you would get a incredibly low compression ratio...

Jeff

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What about using a SRP D16A6 SRP piston that is rated at 11:1 on the A6? I came up with 9.4:1 on the calculator, (which if you read one of my other posts I am not too sure about).

Does it matter if the piston is dished or domed for turbo? Because of course those 11:1 A6 SRP's are domed.

Re:Lower Comp Pistons...
 

After emailing Larry at Endyne here is the latest news concerning ZC FI rollerwave pistons. They will be 75.5mm so you will need to get your block honed. I wasn't planning on doing anything to the block, but now it looks like the way to go for me at least.

"I'm making some higher compression forced induction Roller-Waves. These will be finished in approximately 3 weeks and the CR will be approximately .5 ratio higher than our present pistons for the ZC"

The cr's will be again .5 over what is now available which is 8.23-8.54:1

Now may be a good time to get some if you are looking since this looks like a limited run

Re:Lower Comp Pistons...
 

I called Larry and decided to go with their 8.54:1 pistons, I am going to shave the head .030" and that will boost the compression to 9.15:1.... I figure that going with these pistons instead of a 9.5:1 and losing .4 compression wont be that bad

Re: Lower Comp Pistons...
 

what about a dohc zc with z6 pistons in it?, will the compression be too low?, it should be somewheres around 7.3:1 and what would be safe boost for this?, I was thinking around 15 psi computer is chipped with uberdata with logging adaptor for labtop, factory dohc zc blew at 8 psi , it put a rod threw the block

Re: Lower Comp Pistons...
 

stock comp. for a z6 is 9.2:1 thats y i drop my z6 to 8.5