[blykins]

The more that I look at other people's profiles, the more I see smaller and same size engines making more horsepower. Mine made 484hp and 500 lb-ft. I wonder what my problem is?

Here's the guts:

1979 stock block, 4.060" bore, 4.100" stroke, 425ci.
Main cap girdle
10.5:1
Edelbrock Vic Jr. heads....2.05" I, 1.60" E
Comp Cams Hyd Roller Cam 230 duration, .544" lift...110 LS
Heads bought bare, assembled with springs, shims, etc to match cam.
Vic Jr. intake
Comp roller lifters, Magnum roller rockers
Demon Mighty Demon 750cfm carb
Eagle 4340 ESP crank
Eagle H-beam 6.200" rods
MSD Distributor, 6AL Ignition Box
Ford Racing 9mm plug wires
MSD Coil

Numerous dyno runs....changed timing, ended up with best results being at 12 degrees initial, 36 total. Changed distributor springs....Retuned carb.....ended up with 88's in the front and 98's in the back. Engine was making more horsepower (492) to start out with, but was too lean to be safe.

Peak hp was at 5400, peak torque at 4500.

I think I've mentioned all the essentials.....

One of the things that I think I've done wrong is mismatched the cam with the heads/intake combo. I think the top end is made more for higher rpm use....the cam really necks it down. But that's what Comp Cams recommended with my combo....

Any input is appreciated.....But I'd like to know where I really went wrong....not that 484 isn't enough for a Cobra....but if I stuck the wrong cam in it, I would like to know.