496 Cam Question???
#21
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Originally Posted by SB
Merc 500EFI
Crane Grind#HR-292-2S-14 IG
292,298 at .004” Lift with 1.7 rocker .598” , .610”
230, 236 at .050”
ICL 109 , ECL 119
LSA 114
======================
Merc HP500 Carb
Crane Grind#HR-284-2S-10IG
Adv 284, 292 at .004” Lift with 1.7 .576 / .598
At .050” 222, 230
ICL 105, ECL 115
LSA 110
Crane Grind#HR-292-2S-14 IG
292,298 at .004” Lift with 1.7 rocker .598” , .610”
230, 236 at .050”
ICL 109 , ECL 119
LSA 114
======================
Merc HP500 Carb
Crane Grind#HR-284-2S-10IG
Adv 284, 292 at .004” Lift with 1.7 .576 / .598
At .050” 222, 230
ICL 105, ECL 115
LSA 110
I've been repeatedly told the LSA of 114 makes a huge difference in idle (as it should).
#22
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Hi bcarpman,
You and I may be corresponding about a set of L-29 heads that I have.
Anyway, I have a 1999 7.4MPI (L-29) engine that I have tried different combinations; head mods, cams...
I have consulted with Tyler Crockett, RM Builder, and other vary helpful people here on OSO...
IMO the L-29 heads are not a great choice for a 475+HP 496 stroker.
They will require more work than it is worth and larger intake valves for sure. The heart shaped combustion chamber makes it difficult to install lager valves there for $$...
L-29 heads would be a great choice for building a 420-430HP/454 cube Gen V or Gen VI from a 300-330HP base engine...
An HP500EFI is a great cam choice. I bought a take-out from Strippoker and will be installing it in my 502 soon.
You and I may be corresponding about a set of L-29 heads that I have.
Anyway, I have a 1999 7.4MPI (L-29) engine that I have tried different combinations; head mods, cams...
![Roll Eyes (Sarcastic)](/forums/images/smilies/rolleyes.gif)
I have consulted with Tyler Crockett, RM Builder, and other vary helpful people here on OSO...
![Cool](/forums/images/smilies/cool.gif)
IMO the L-29 heads are not a great choice for a 475+HP 496 stroker.
They will require more work than it is worth and larger intake valves for sure. The heart shaped combustion chamber makes it difficult to install lager valves there for $$...
![Roll Eyes (Sarcastic)](/forums/images/smilies/rolleyes.gif)
L-29 heads would be a great choice for building a 420-430HP/454 cube Gen V or Gen VI from a 300-330HP base engine...
![Cool](/forums/images/smilies/cool.gif)
An HP500EFI is a great cam choice. I bought a take-out from Strippoker and will be installing it in my 502 soon.
![Big Grin](/forums/images/smilies/biggrin.gif)
__________________
Patrick
Patrick
#23
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Originally Posted by SB
I used an equation that helps us see if we are in the ballpark for valve lift vs head flow vs CID vs peak hp rpm.
Using 454cid with cfm I posted above for these heads:
.500 lift cam = 4283 rpm
.600 lift cam = 4587 rpm
Using 496cid with the cfm I posted above I get:
.500 lift cam = 3921 rpm.
.600 lift cam = 4199 rpm.
Using 454cid with cfm I posted above for these heads:
.500 lift cam = 4283 rpm
.600 lift cam = 4587 rpm
Using 496cid with the cfm I posted above I get:
.500 lift cam = 3921 rpm.
.600 lift cam = 4199 rpm.
#24
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Just curious how this project went and second I know Raylar and Tyler Crockett are the gurus regarding the 496, but I'm on a sorta budget regarding my upgrade project and am looking at either just buying a stock HO cam and finding a good flowing set of heads and having them worked or could someone else make a recommendation on a little more agressive cam than the HO and some good aluminum heads that will bring the 496 alive?
Thanks...Oh by the way I'm not the engine builder on this project so when you start talking duration etc. I'll be lost.
Thanks...Oh by the way I'm not the engine builder on this project so when you start talking duration etc. I'll be lost.
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