How much power would i loose if....
How much power would i loose if.... How much power would i loose if i built a lower compression motor for boost. Lets say 8.5 or 9 to 1 with big heads and cam etc etc, but dont have a turbo/supercharger installed right away? I have the $ for a motor and supporting mods, but not a turbo kit yet. Just wondering if it would be a very significant amount and if im being dumb even considering this. Would it be like 50/100 HP on a 500 FWHP application or what? Just wondering if i build a motor if ill have to stare at it on a stand for a while till i get the turbo/supercharger for it, or if i can run non boosted for a bit and still have some fun.
My recomendation would be to go ahead and built/install your low compression motor. This is the exact approach I have taken on my project. I'm current running a low compression 402. Latter in the year I'm going to be installing a turbo. My 402 is making more hp & tq with 8.3:1 than my head/cam 346 with 11.0:1 (438 rwhp/397 rwtq). When I was considering my buildup I decided that I wanted to spread out the $ and time required for the buildup since I'm doing the installation myself.
Here's a car that runs pretty good with lower compression on the cheap 87 octane after some tuning.
https://ls1tech.com/forums/vehicles-sale-lsx-powered-only/498465-98-c5-corvette.html
https://ls1tech.com/forums/vehicles-sale-lsx-powered-only/498465-98-c5-corvette.html
Originally Posted by ozws6
My recomendation would be to go ahead and built/install your low compression motor. This is the exact approach I have taken on my project. I'm current running a low compression 402. Latter in the year I'm going to be installing a turbo. My 402 is making more hp & tq with 8.3:1 than my head/cam 346 with 11.0:1 (438 rwhp/397 rwtq). When I was considering my buildup I decided that I wanted to spread out the $ and time required for the buildup since I'm doing the installation myself.
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I did the same thing a while back in my 3rd gen. The combo was:
360 cid SBC, 8.5/1 compression
AFR 210 Race Ready's
GM847 cam (234/242-112)
Victor Jr. and Holley 750
1 3/4" shorty headers
This ran 11.96 at 114.5 mph. Not too bad I guess.
I later gave up on the forced induction idea and decided to up the compression and stroke it. I did nothing other than change the short block to an 11/1 383 and the car ran 11.33 at 120.5 the very next trip to the track.
In general, 1 full point of compression is worth 5% hp.
360 cid SBC, 8.5/1 compression
AFR 210 Race Ready's
GM847 cam (234/242-112)
Victor Jr. and Holley 750
1 3/4" shorty headers
This ran 11.96 at 114.5 mph. Not too bad I guess.
I later gave up on the forced induction idea and decided to up the compression and stroke it. I did nothing other than change the short block to an 11/1 383 and the car ran 11.33 at 120.5 the very next trip to the track.
In general, 1 full point of compression is worth 5% hp.
