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Old 06-04-2015, 11:44 AM   #6
hotlap


 
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Drives: 20 1LE 2SS M6 Rally Green
Join Date: Mar 2014
Location: Franklin WI
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Quote:
Originally Posted by IOMike View Post
I'm not sure what all the hype about the flat plane crank is....maybe Ford is sandbagging and it's far more impressive than the dyno graph shows. What I see though, is a engine that almost matches the 10 year old LS7. Hold off on the 5.2 vs 7.0 because that 5.2 as we know is a lot bigger than the 7.0.
Voodoo makes power by virtue of engine speed (inertia) whereas the LS7 uses displacement. I.e. Power is the rate that torque can be applied but the FPC engine needs the inertia of the vehicle for this and is why the curve is so poor at low rpm. It's power is a function of engine speed. LS7 high T, low rpm, Voodoo low T, high rpm

HP = (torque x RPM) / 5252

A light car with momentum will go like hell with the Voodoo. Knock it off its rpm and it will need time to recover. A LS7 uses pure grunt (displacement). So the Voodoo needs 3,500 rpm to match the LS7 torque at 1,000 rpm.

If you compare the engines in their intended rpm range, Voodoo has the power edge (4500 to 8200) whereas the LS7 has the torque edge (3500 to 7000)
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Last edited by hotlap; 06-04-2015 at 12:07 PM.
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