427 FE Horsepower numbers.
 

Hello. I am considering building a 427 SO for my 1966 Fairlane.It will be used for a street/strip car with more street than strip. I plan on using a 427 SO block, bored .030 over. Also, I was thinking about using high-riser heads and a 2x4 intake. The cam I am thinking about using is a Comp cams mechanical roller with 262 duration, .672 lift and 110 lobe separation angle. :JEKYLHYDE. What I really need help with is the pistons. I want to run forged pistons with at least 10.2 compression, but more toward 10.5. What kind of power will I be looking at? is this too much cam for the street? Can someone run this through desktop dyno and find what would yield the best HP?

Joker

Would love to help, but this is over my head.

Sorry.

CB

A couple of thoughts on building an FE for the street. I've done it and gave it a LOT of thought!

I had 12.5 to 1, roller solid cam, high rise heads and 2X4 intake. Man what a beast that thing was. It was making over 600 horse. Finding high enough octane was a constant problem and it got old fast. I mostly ran with retarded timing so I wouldn't have to worry so much about the octane\detonation problem. Retarded timing and pump gas lost a lot of horse power, after awhile I figured "whats the point" of having BIG horse power if you can't DRIVE the dam car on the street without a major head ache? Then a roller lifter broke after about 8000 miles ONLY and I decided it was time for MAJOR overhaul of both the motor AND the "build specifications".

I went with 9.8 to 1 compression, anything higher and you got a problem with "pump gas". 9.5 is actually recommended. The high rise iron heads have pretty small CC combustion chambers so I had to special order "dished" pistons to get the C.R. down. I also went with a FLAT TAPPET cam because the "life span" of a roller cam in an FE is just not "that long". Comp Cam 282 solid has been the PERFECT cam for what I wanted. 500 horse and STREETABLE. Shift at 6000-6200 rpm.

Because the torque curve has been moved down in the rpm range the motor FEELS as strong as it ever was and pulls nicely from about 2300 rpm and up. The old cam didn't run well at all below 3000 (and got 6 mpg, now I'm closer to 10 mpg). I also changed the carbs from mechanical secondary to vacuum for a smoother application of power.

Speed in the 1/4 dropped from 11.90 to 11.99. Good enough for me! I gave up VERY little speed (can't "feel" the difference) and gained FAR more "drivability". For me, 500 horse is "enough". With 600 plus I couldn't put the power to the pavement because of traction loss anyway!

Your specs above should yield 500 horse more or less is my guess. But with that compression you will be constantly searching for better gas\octane.

There is more to this engine design thing than JUST cam, C.R. and intake. I found more power by paying close attention to the "quench" area and compression HEIGHT of the piston. Tricky stuff and VERY important if your running "borderline" C.R. and expect to use pump gas. In addition the FE's have unusual clearance specs internally, get that wrong and your motor WILL NOT live long. Chamfer the oil passages, grind down the sharp edges and make sure you got enough rod and bearing clearance. It's an "art" building an FE.

That roller may......,be fine for the street but, it seems a little high. Reason being, the lifters won't live long with all the stoping & going & thier expensive. I have a 428 & bored it .60 over. 10:4:1 compression. Medium riser heads with extensive porting/polishing. I went with a solid, easy on the valve train & a lot cheaper than rollers. I had Comp cams custom grind my cam. It's for street & strip. 252/260 duration @ .50 600 lift, 110 lobe sep. Idles apx. 1,000 rpm with a manual tranny. Pump gas for the street but, race fuel for the strip. It dynoded at 536 H.P . Does not over heat. I adjust the valves twice per year. For me, it's a very good combination. We like to travel so I did not build it so radical, that it wouldn't be road worthy.
Kev

Plus those solid lifters are cheaper, last longer, and give the lumpy exhaust we are all after.

Chris

My 427 is somewhat close to that - I have a little more cam Edelbrock heads. My bore is .005 over standard, 10.9:1 compression, LeMans crank, etc., etc. and have an average of 645 hp. A good source for roller cams is Keith Craft Racing - they do allot of these systems. Hope this helps!