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06-29-2006, 09:13 AM
#5
Yes and no. Power/torque peaks are mainly determined by your intake valve closing point. A later IVC will typically give you a later power/torque peak.
If you take the exact same duration and only change the LSA, a 114LSA cam will have a later power peak. But look at this:
224/224 112LSA (+0) = IVC 44 degrees ABDC (6200 rpm peak)
224/224 114LSA (+0) = IVC 46 degrees ABDC (6300 rpm peak)
But when you add advance to it:
224/224 114LSA (+4) = IVC 42 degrees ABDC (6100 rpm peak)
Notice? Wider LSA, earlier power peak. Intake centerline is another really important consideration in determining where your power/torque peaks. I haven't even included duration into this equation (which would take a few more paragraphs to explain).
If you take the exact same duration and only change the LSA, a 114LSA cam will have a later power peak. But look at this:
224/224 112LSA (+0) = IVC 44 degrees ABDC (6200 rpm peak)
224/224 114LSA (+0) = IVC 46 degrees ABDC (6300 rpm peak)
But when you add advance to it:
224/224 114LSA (+4) = IVC 42 degrees ABDC (6100 rpm peak)
Notice? Wider LSA, earlier power peak. Intake centerline is another really important consideration in determining where your power/torque peaks. I haven't even included duration into this equation (which would take a few more paragraphs to explain).
__________________
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.
06-29-2006, 09:16 AM
#6
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Originally Posted by Patrick G
Yes and no. Power/torque peaks are mainly determined by your intake valve closing point. A later IVC will typically give you a later power/torque peak.
If you take the exact same duration and only change the LSA, a 114LSA cam will have a later power peak. But look at this:
224/224 112LSA (+0) = IVC 44 degrees ABDC (6200 rpm peak)
224/224 114LSA (+0) = IVC 46 degrees ABDC (6300 rpm peak)
But when you add advance to it:
224/224 114LSA (+4) = IVC 42 degrees ABDC (6100 rpm peak)
Notice? Wider LSA, earlier power peak. Intake centerline is another really important consideration in determining where your power/torque peaks. I haven't even included duration into this equation (which would take a few more paragraphs to explain).
If you take the exact same duration and only change the LSA, a 114LSA cam will have a later power peak. But look at this:
224/224 112LSA (+0) = IVC 44 degrees ABDC (6200 rpm peak)
224/224 114LSA (+0) = IVC 46 degrees ABDC (6300 rpm peak)
But when you add advance to it:
224/224 114LSA (+4) = IVC 42 degrees ABDC (6100 rpm peak)
Notice? Wider LSA, earlier power peak. Intake centerline is another really important consideration in determining where your power/torque peaks. I haven't even included duration into this equation (which would take a few more paragraphs to explain).
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06-29-2006, 09:33 AM
#9
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Originally Posted by orangeapeel
That 114+ will spread it out more over the band.
ahhhh, that exactly what i was looking for....... so the 114 has a broader powerband and the 112 has a narrower power band?
