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Old 06-05-2008, 11:14 PM
bulldog426's Avatar
bulldog426 bulldog426 is offline
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Default hows this cam

was looking at this cam for my 440, but i'm putting in kb dome pistons, and was wondering if i would have problems with the valves hitting the pitons with the .513 lift.

http://lunaticamshafts.com/Product.aspx?id=1579&gid=287


heres the cam i got sitting in my bedroom right now, but was thinking about sending it back.
http://compcams.com/Cam_Specs/CamDet...?csid=700&sb=0

the lunati has a wider rpm range, but i'm wondering how much compression i would lose with the larger lift. wish i could find out the specs on the stock 440 cam, because to me the comp don't seem like it's much more than a stock cam.
has anyone ever used either one of these heads??

it's a 440 going in a 72 charger street screamer, with 83/4 suregrip outback, with good gear. getting kb dome pistons, that have a 9.9 compression rating with 90cc heads.
i'm probably going to use the stock 452 heads, mildly ported, or a set of 906s if i can get em from the guy. headers, then match the intake and carb to the rest of the motor. i'm putting it together for something to have fun in, burn the tires down, auto trans with aftermarket converter, i'm looking for a good bit of power out this thing, and still maintain streetable behavior.
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Old 06-06-2008, 12:48 AM
rampage_82 rampage_82 is offline
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Default

That Comp cam is an older design, and that Lunati Voodoo is going to be a much stronger performer. That .513" lift is no problem with the KB pistons, in fact you can go to well over .550" with those pistons. If you're looking for someone to talk to about camshafts, I would check out the Racer Brown .. www.4secondsflat.com.
Most of the time you can make the 452 heads perform just as well as the 906, and in fact a lot of people prefer them to the 906's. Don't worry about the compression loss with the Lunati cam. It is still a fairly mild cam all things considered. Also don't get so hung up on theoretical compression ratios, they don't mean as much as the cranking PSI. I.E. My 440 (theoretically 10.4.1 CR) with the COMP .292 adv. hyd, .501 lift 244 @.050, and 110 degree lobe center, would have a cranking PSI of 185 lbs. My buddies 12.5.1 CR 327 chebby, with a smaller cam would only have a cranking PSI of 130 PSI. You can get away with a lot more cam in a big block than you can a small block..
I think you could go with a little bigger cam, than even that Lunati and still be fine. However that's just my .02....
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Old 06-08-2008, 03:16 PM
451Mopar 451Mopar is offline
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Both cams are pretty mild on duration and lift, I don't think valve clearance will be a problem, but it's alaways best to test check the clearance because the cams installed position.
Make sure you have the correct timming gear. Looking at the links, the Comp cam is a single bolt, and the Lunati is a 3-bolt design.
The cams lift dosen't have much to do with compression ratio, other than help define the cam profile. The intake closing point is what matters because compression does not start building untill the intake valve closes.
In comparing the intake closing points:
a smaller cam that closes the intake early will build more compression which really helps low end torque, but too much cylinder presure can also cause detonation on low octane fuel. A bigger cam that closes the intake later will loose some low end torque, but is less likely to ping on pump gas, so there is a ballancing act between the static compression ratio, and the cranking cylinder pressure.

FWIW, Hughes has a 228/232 duration cam with 0.558"/0.576" lift.
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