Well I have an a6/z6 setup with a built a6 block. I bought the block off someone when it had 2k miles on it. It has z6 srp pistons, eagle rods, acl bearings total seal rings. I did not do enough research in the beginning and have recently found out that my compression is 10.5:1. Currently i am running 12psi. I am debating whether or not i should keep turning the boost up or if i should take everything out of my block and swap it over to a z6 block.

Obviously lower compression is better but who is running 10:1 or higher compression with more than 10psi? I know ill make more power with the higher compression but is it worth the trade off? How much more power does one make with the higher compression? I am shooting for 350-400whp


Modified by 1TurboHatch at 7:11 AM 4/24/2005

 

I just saw a sig, B18c1@11.5:1, 17-18psi... Granted you have a d-series, its usually the limit of stock internals (and then stock sleeves with forged internals) that determines the maximum [hp from] boost. I can't vouch for max psi of stock z6 sleeves, but my guess is that 12psi@10.5:1 with forged goodies is still on the safe side. 350-400whp from a stock sleeved block & forged innards is hard enough on an LS, let alone a d-series. If you do have sleeves and extensive headwork, I'd say push it till you hit your numbers.

 

The head is stock at the moment. I have read of a few d series going 450+ on stock sleeves. I am just debating on whether or not i should take the time and money to put all my internals into a new block or boost it the way it is.

If the gain from higher compression is a lot then it might be worth trying to push it. I have yet to run it at the track or even dyno the car so i have no clue where i even stand at 12psi. I would like to know what high compression d series motors make on 10-15psi. I mean if im at say 300 right now then it might be worth it to push it a little more but if im way at say 250 then it might be worth it to rebuild the block.

 

The compression will limit the amount of HP you are looking for on pump gas.

The only way to find out the motors limits is tuning.

 

What are the limits of high compression dseries with forged internals and stock sleeves on 93 octane?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1TurboHatch &raquo;</TD></TR><TR><TD CLASS="quote">What are the limits of high compression dseries with forged internals and stock sleeves on 93 octane?</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Bryson &raquo;</TD></TR><TR><TD CLASS="quote">The only way to find out the motors limits is tuning. </TD></TR></TABLE>

 

Well obviously i could find out the limits by just pushing it but i dont want to be shooting from the hip. Id like somewhat of an idea what people have pushed with high compression motors on pump gas or if its even worth the extra hp from the higher compression to risk it.

 

I have thought of adding a thicker headgasket to lower it down a bit but i have tried it before on a focus and had it blow so i have kind of shyed away from that. How thick of a headgasket would i have to get to lower it 1 point?

 

currently running 11.2-1 cr b20vtec turbo .....(in search of good aem ems tuner)

 

TTT

 

TTT WHATS THAT?

 

To The Top...Although, I'm not really sure what this guy is looking for. I told him the only true answer to his question.

 

triple twin turbo

 

I am looking for opinions and people that have done this before not just statements saying that the limits are found by trying things out which is obvious.

 

what are your pistons compression

 

I have run both, and can say that running low compression is best because you can have the most power with pump gas.

Compression will just limit the amount of power you can tune for on pump gas. For those who say that the higher compression will increase off boost response, have obviously never played with timing.

But...If your just stuck with your high compression setup, just run boost and tune it. You can run decent boost as long as you pull the right amount of timing.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1TurboHatch &raquo;</TD></TR><TR><TD CLASS="quote">Well obviously i could find out the limits by just pushing it but i dont want to be shooting from the hip. Id like somewhat of an idea what people have pushed with high compression motors on pump gas or if its even worth the extra hp from the higher compression to risk it. </TD></TR></TABLE>

I have a D16Y8, SRP Pistons, Eagle Rods, running just slightly over 10:1 C/R.

I street tuned to 15psi on 93 octane, but only managed to dyno to 10.5psi due to some dyno problems. Anyways I made 272whp at 10.5psi so I would imagine I'm making somewhere around 320-330whp at 15psi.

 

Yea see im at like 10.4-10.5:1, so i should be right around the hp you are making, im running 12psi with the same build pretty much. Do you have any headwork or anything besides the built block? What are you using for tuning? Im using uberdata. What is the most boost you would run with your setup.

 

PMed ya.

 

Yea i'm shocked at the numbers you made on only 10psi Ryan. They are really impressive . Makes me want to ditch my dinky turbo...

 

Ryan CIvic, we have very similar setups, I was just wondering what turbo you were running?

 

sc50, by the way way ryan how much extra hp do you think the cam made? Is it a zex cam?