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Discussion Starter · #1 ·
All of you engine experts... what is your rough guess on my rear wheel horsepower?

302 bored .030 over.
Cast iron heads, ported with thermactor humps removed, and gasket matched on intake and exhaust side.
Flat-top Hyperutectic pistons, with 9.3:1 compression.
Edelbrock Performer, Ported and polished. Holley 650 CFM 4 barrel carb.
Long tube headers, no mufflers into X-pipe and out the side.
Camshaft is the same as a comp cams 270H. I have a C4 automatic with a 9 inch rear end. The rear end has a detroit locker and 4.11 gears. What do you think my rearwheel horsepower will be? Also, what about tourqe. I know you cant be exact on this, but I want a guestimate. Thank you all...
 

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Discussion Starter · #5 ·
Desktop dyno says I should be making 326 flywheel horsepower at 5500 RPM, and 354 lb ft of tourqe at 4000 RPM. If you subtract 20% off of both numbers, I get 260 horsepower, and 283 lb ft of tourqe. So is this way off, or what?
 

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well.....what flow numbers did you put in for your heads?
They are stock heads that you are working, so those numbers are impossible to estimate to get a valid desktop dyno number IMO
 

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.8 to 1.05 flywheel HP/CI, depending on state of tune. CR is limiting factor, along with head build state.

ET's/MPH should be in the 13.90-14.10 range at around 100 mph...

I beat a lot of Chevies with this combo back in the 70's...*G*
 

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Desktop dyno says im supposed to be making 512 hp at 6000... but right now, thats not even close. ::
 

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I would put the horsepower from your combo at 275-285 horsepower at the flywheel....with close to 260-275 ft lbs of torque.

Only a real dyno and good tuning will tell of the engine's real potential.
 

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A buddy of mine built a 302 using Powerheads, Edlebrock intake, carb, Tri-Ys, MSD ignition, similar profile Cam and he ended up with 195 RWHP.

So, ya I think 260 RWHP is way optimistic ::
 

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In my opinion the desk top dyno is worthless.I dynoed my car and it put out 110 less horsepower than the desktop.I will say under 200hp at rear wheels. :p
 
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