DCR's turbo engines?
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DCR's turbo engines? I've read quite a lot about DCR's for n/a engines and it's recommended that 8 or 9:1 seems about ballpark. I can't find anything relating to turbo engines. I understand detonation etc but if going for a low dcr on a blown engine there would be little point in using boost in the first place unless the reason is to prevent detonation etc. Maybe if stock c/r can't be reduced then reduced dcr would be helpful.
My logic suggests I should stick to the above levels maximum or a bit less (to reduce pumping losses) for a 7000 rpm redline on low boost. Conversely, I'd expect to use much higher dcr's if I was revving to a hypothetical 10'000 rpm n/a.. Am I on the right track with this? For high boost would you pick a cam giving lower dcr's of around 6-7:1?
Anybody got any comments or seen any links relating to forced induction dcr's they could share? Thanks.
Boosted.
My logic suggests I should stick to the above levels maximum or a bit less (to reduce pumping losses) for a 7000 rpm redline on low boost. Conversely, I'd expect to use much higher dcr's if I was revving to a hypothetical 10'000 rpm n/a.. Am I on the right track with this? For high boost would you pick a cam giving lower dcr's of around 6-7:1?
Anybody got any comments or seen any links relating to forced induction dcr's they could share? Thanks.
Boosted.
Last edited by Boosted LS1; Apr 17, 2007 at 03:11 PM. Reason: To add text.
Moved from advanced tech.
For a pump gas turbo car, a DCR of 6.5-7.0:1 is a good place to be.
For a pump gas turbo car, a DCR of 6.5-7.0:1 is a good place to be.
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2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
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Originally Posted by Patrick G
Moved from advanced tech.
For a pump gas turbo car, a DCR of 6.5-7.0:1 is a good place to be.
For a pump gas turbo car, a DCR of 6.5-7.0:1 is a good place to be.
I am still confused about this "Boosted DCR" thing (easy to do...) The LPE GT2-3, their self described super charger cam, puts the DCR right at 8.05ish on an all factory LS1. I know they (LPE) have sold a ton of these cams, specifically to people using them in super charged factory LS1 applications.
Are these numbers too high? I know we have not covered the level of boost but for argument use 7#s of boost/93 octane...
