boost/compression question

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Oct 28, 2013 | 06:40 AM

02sslayer

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From: longview, wa

boost/compression question

I am pretty new to boost and have a question im sure someone can answer. If im running 11.75:1 CR can I run a -1.0 -2.0 headgasket to get my compression down? Or is running a thick head gasket like that not safe to run boost? Thanks in advance every one

Oct 28, 2013 | 06:53 AM

BMF_Racing

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what are your goals with this combo? What fuel? What comp ratio are you wanting? Street car or race only?

Oct 28, 2013 | 08:46 AM

HexenLord

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A thick head gasket will get you down safely into E85 range, but you'll still be pretty high. 93 and water/meth will let you get some decent boost. Just remember that your going to be a lot more limited than a low compression setup so don't get greedy and tune conservative.

Oct 28, 2013 | 09:14 AM

02sslayer

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From: longview, wa

Quote:

Originally Posted by HexenLord

I dont want to run a lot of boost. Motor is 416ci, 11.75:1 CR afr 230 heads 240/250 113 cam. 90% street 10% race. Motor is not even built yet but I have most of the parts. I also have callies h beam rods, callies compstar crank and wiseco forged pistons with reliefs. Motor is sposed to make 550rwhp NA but I am wanting more in the 800-900 range. I dont think I need a great deal of boost to get there. Id be using turbonetics gtk 1000 for turbo. Just think 11.75:1 is a little much for boost...

Oct 28, 2013 | 09:15 AM

02sslayer

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From: longview, wa

I dont know for sure what CR id want yet but I think 10.5:1 would be good for low boost

Oct 28, 2013 | 09:20 AM

Wicked69

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I have done it both ways. I have run 11.0 compression and low boost and I am now running 8.5 compression and tons of boost. With the 11.0 I ran very conservative timing, ie 14 degrees at full boost. Now that I am running low compression I run around 20 degree's at full boost. I run pump E85. As long as you can have the discipline to keep the timing low and the boost low you will be fine. I wasn't. lol I ran a 6.04 in the high compression set up and wanted that five second pass so bad I got a little greedy and BOOM!

Oct 28, 2013 | 09:44 AM

Forcefed86

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Quote:

Originally Posted by 02sslayer

Yes you can. It's done in the import world all the time. I ran a 3mm thick HG on my 2jz motor. Took me from 10:1 to about 8.5:1. I ran 28lbs on 91 pump gas with meth inj.

Last edited by Forcefed86; Oct 28, 2013 at 01:45 PM.