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Old 07-04-2005, 05:11 PM
MidOHasp MidOHasp is offline
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Join Date: Jul 2003
Location: Cleveland, OH
Cobra Make, Engine: SPF1670 Stroked Little Windsor - Runs OK.
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Brent,

IMO, the HP gains shown on DD2K when comparing a single plane to a dual plane are not the most accurate. I am basing this off comparing my dual plane motor (508 HP @ 5800 RPM) to similar motors running single plane intakes (Vic Jr).

To me, it is all about parts matching. I swear by this.... up and down. To me, it is SOOO important.

I threw "smallblock fords for cobra replica convention" to the wind and started with a blank piece of paper.

Ran the Comp Camps XE 282 HR cam:

.565" intake lift
.574" exhaust lift

232* intake duration (@ .050")
240* exhaust duration (@ .050")

RPM Air-Gap intake manifold

AFR 185 cc heads

Speed Demon 750 DP

408 ci

People told me 185cc heads were too small, that the RPM was too small, etc.. etc.. etc......

But on the dyno, it pulled 508HP and 544TQ. Torque curve was flat and very very wide. Over 500 from 3200 to 5400 or something ridiculous.

Had we gone with the 205cc heads, that would have dictated the Vic Jr. Which would have dictated one or two notches up on the cam (closer to 600 lift and 250* duration).

That would have been nice and hairy, but...max power would have been happening at 6800-7000 RPM.

I shift a little past max power (6300) right now and that is great.

I wouldn't want to be pushing 7000 RPM regularly with a 2-bolt 351 block, even though the rotating assembly is good well past 7000.

The engine has seen north of 7000 RPM, accidentally, and it was fine. But those are territories I don't want to chart on a vintage 2-bolt block.

Maybe w/ a Dart or other aftermarket block.

My advice is to not look at one piece individually such as the cam. Decide what kind of engine you want, where you want it making fat torque and peak power, where you want to shift it, and start matching parts together. Don't put a cam that is too big with heads that are too small or vice versa.

I can't tell you how important that advice is...I am a real happy camper having spent a lot of time doing what you are doing right now...bench racing. It did pay off!
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