Heads, 10 CFM difference equals how much rwhp?
05-15-2005, 04:30 AM
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Heads, 10 CFM difference equals how much rwhp? Let's say you have two identical engines, but the heads on one of them flow 10 CFM more on both the intake & exhaust. How much additional rwhp is that engine going to make?
05-15-2005, 10:33 AM
#4
FormerVendor
Originally Posted by xxxhp
Let's say you have two identical engines, but the heads on one of them flow 10 CFM more on both the intake & exhaust. How much additional rwhp is that engine going to make?
05-15-2005, 11:39 AM
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Originally Posted by racer7088
<snip>
It's all relative as if the head is too big you may even lose power. If you had a 302 and you had a 200cc head that went 320 cfm it would probably make more power everywhere than a 300cc head that went 400 cfm because the bigger head wouldn't even get into a normal velocity range until the rpm zone thet pushrod engines hardly work in anyway!
<snip>
There's more than just flow numbers but if the heads are both well designed then the flow will matter provided the engine actually needs it or can use it all up.
It's all relative as if the head is too big you may even lose power. If you had a 302 and you had a 200cc head that went 320 cfm it would probably make more power everywhere than a 300cc head that went 400 cfm because the bigger head wouldn't even get into a normal velocity range until the rpm zone thet pushrod engines hardly work in anyway!
<snip>
There's more than just flow numbers but if the heads are both well designed then the flow will matter provided the engine actually needs it or can use it all up.
Don't tell Jay Allen that!!!!!
Ed
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05-15-2005, 06:51 PM
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Originally Posted by 98t56TA
Nope. That magazine blows.
HC50 "used to be" a damned good site until one of the new
"sponsors" started dictating "what" should be said and "who" should be able to say it.Wait... is this now a trend on all sites???
Ed
05-15-2005, 06:53 PM
#10
Originally Posted by EDC
One should not pre-judge without knowledge.
HC50 "used to be" a damned good site until one of the new "sponsors" started dictating "what" should be said and "who" should be able to say it.
Wait... is this now a trend on all sites???
Ed
HC50 "used to be" a damned good site until one of the new
"sponsors" started dictating "what" should be said and "who" should be able to say it.Wait... is this now a trend on all sites???
Ed
05-16-2005, 12:57 AM
#14
FormerVendor
Originally Posted by EDC
Geez Erik...
Don't tell Jay Allen that!!!!!
Ed
Don't tell Jay Allen that!!!!!
Ed
05-20-2005, 09:54 PM
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Originally Posted by 98t56TA
Mustang 5.0 is a magazine. I used to browse through it while watching TV years ago but got bored after a while with the run on sentences that didn't make sense.
HC50 = www.hardcore50.com
"not" a magazine...
Ed
05-21-2005, 09:24 AM
#17
Originally Posted by xxxhp
Let's say you have two identical engines, but the heads on one of them flow 10 CFM more on both the intake & exhaust. How much additional rwhp is that engine going to make?
__________________
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
2018 Cadillac Escalade 6.2L A10 Pat G tuned.
LS1,LS2,LS3,LS7,LT1 Custom Camshaft Specialist For custom camshaft help press here.
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
2018 Cadillac Escalade 6.2L A10 Pat G tuned.
LS1,LS2,LS3,LS7,LT1 Custom Camshaft Specialist For custom camshaft help press here.
Custom LSX tuning in person or via email press here.
05-21-2005, 11:27 AM
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Originally Posted by Patrick G
Erik answered the question best: On a fully developed motor with optimized intake and exhaust and ideal cam timing, you'll see 2 hp for every 1 cfm increase. However, since most LSX motors are not optimized to this point, realistically, you'll see around 1-1.5 rwhp increase for every 1 cfm increase. If you get heads that flow 10 cfm more and have similar air speed, you should see 10-15 more horsepower to the tires. Does that answer your question?
. Thanks everyone for the info 
