408W or 427W

[Dana E.]

Long story short: sold the 393W so now it's time for a new motor. 393 was a 10.5 compression, factory block, with Dart Pro 1 195CC heads. Cam was a Comp XE282HR hydraulic roller 232/240 @ .050, .565./.574 lift 112* lobe separation. It was a strong runner, near as I could tell in the 173 miles that motor lasted.....and no, I did not build that motor, and yes, I won't make that mistake again.

This time around I'm going with a Dart SHP block and probably a forged Eagle rotating assembly, unless a Scat rotating assembly is better. I've read that the rod side clearance is a bit excessive with the Eagle cranks. Any truth to that? The Scat crank in the 393 looked like a decent piece. I will be reusing the Performer RPM Air Gap manifold and the Holley 750 Ultra Double Pumper from the 393.

I'm looking for an honest, streetable 500+ horsepower. A lot of people run a 408, but I'm leaning towards a big bore (4.125 bore X 4.00 stroke) 427. 10.5 to 1 compression. AFR 205 heads, or should I go bigger? Dished pistons and small combustion chambers or flat tops and bigger chambers? Any power difference between the two? What about Keith Craft Brodix heads or World Products 18* Man-O-War heads? The Comp XE282HR would probably idle like a stocker in a 427. I'm thinking maybe a Comp XR294RF-HR 242/248@ .050, .576/.600 ground on a 5.0 core (not a reduced base circle), and maybe widen the lobe separation from 110* to 112*. I'm sure I'm leaving some HP on the table reusing the manifold and carb, but hey, it should be a torque monster.

Sorry about the long-winded post, but fire away with any comments or suggestions.