540 cam selection ???
05-09-2004, 07:59 PM
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540 cam selection ???
i could use some good advice on cam selection..
here is what i have...
dart 9.8" deck block bored to 4.5
4340 steel crank 4.25 stroke
6.385 4340 H beam rods
je srp pistons 8.7:1 or 9:1 comp
GM 049 large ovals exh inconel 1.88" intake stain 2.25"
performer intake
850 holly carb
merc/gil hp 500 exhaust
DUI ignitions
like to run on pump gas,and idle
top rpm 5500
would like to go hyd roller cam
thx in advance
X
here is what i have...
dart 9.8" deck block bored to 4.5
4340 steel crank 4.25 stroke
6.385 4340 H beam rods
je srp pistons 8.7:1 or 9:1 comp
GM 049 large ovals exh inconel 1.88" intake stain 2.25"
performer intake
850 holly carb
merc/gil hp 500 exhaust
DUI ignitions
like to run on pump gas,and idle
top rpm 5500
would like to go hyd roller cam
thx in advance
X
05-09-2004, 08:25 PM
#2
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XCAV8,
If you haven't already bought your intake I would go with the Dart single plane for oval port heads! Trust me on this! I would also go with the Holley 800CFM carb, it will be more than enough for that motor in that RPM range.
As far as the cam, I would go with a Comp Cam hydraulic roller, custom Grind! Somewhere in the 240- [email protected] lift on the intake and [email protected] on the exhaust side! You don't need to go crazy with the lift around .600 to .625 range. Have it ground with a 112 lobe seperation angle and install it around 110 degrees intake lobe centerline. This combo will make tons of torque and allow you to turn a lot of prop for good top end! Keep in minfd that you will need to have almost dry, if not dry exhaust to avoid reversion!
You are going to love the DUI ignition.
If you haven't already bought your intake I would go with the Dart single plane for oval port heads! Trust me on this! I would also go with the Holley 800CFM carb, it will be more than enough for that motor in that RPM range.
As far as the cam, I would go with a Comp Cam hydraulic roller, custom Grind! Somewhere in the 240- [email protected] lift on the intake and [email protected] on the exhaust side! You don't need to go crazy with the lift around .600 to .625 range. Have it ground with a 112 lobe seperation angle and install it around 110 degrees intake lobe centerline. This combo will make tons of torque and allow you to turn a lot of prop for good top end! Keep in minfd that you will need to have almost dry, if not dry exhaust to avoid reversion!
You are going to love the DUI ignition.
Last edited by TomR; 05-09-2004 at 08:29 PM.
05-09-2004, 09:02 PM
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thx tomR
i'm really looking for a cam i can run wet and not worry about reversion... well yes i already have the intakes..
i always thought the single plane was more for higher rpm.. ??? and i already have the carbs...
i'm really looking for a cam i can run wet and not worry about reversion... well yes i already have the intakes..
i always thought the single plane was more for higher rpm.. ??? and i already have the carbs...
05-10-2004, 07:56 AM
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No. That engine was way under cammed. It was also a flat tappet cam. If you really don't want a reversion issue, just pick one size smaller, the 731.
05-14-2004, 10:19 PM
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Originally Posted by JimV
Those heads are going to run out of poop at .550 lift I wouldn't run much more lift than that. 540ci requires a lot of air to feed it. You may need more duration than you think to make any power at 5000 rpm. my 2
