Why high compression?
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TECH Enthusiast
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From: Orange Park FL
Why high compression Why are our cars such high compression and most new cars. From what i've read on engine compression going up a point in compression is only about 10hp give or take. Is 10hp worth the extra 20 cents a gallon or am i just missing something.
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Joined: Aug 2004
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From: Portland Oregon
It's right out of the Physics book, compression = Power.
The number I have always heard is 1 point compression = 5% HP
On a 400 hp engine, an increase of 10:1 to 11:1 = 20hp
You will need high octane fuel.
The number I have always heard is 1 point compression = 5% HP
On a 400 hp engine, an increase of 10:1 to 11:1 = 20hp
You will need high octane fuel.
Higher compression makes a motor more efficient. More efficient means better fuel economy. If our motors were only 9.0 to 1, we might only be getting 24 mpgs, but with 11 to 1, we can get 26-30 mpgs. That's usually worth the bump to premium fuel, plus you get lots more torque to pull you around town. Heck, diesel engines have sky high compression and look at the great fuel economy they get. Efficiency, efficiency.
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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.
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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.