Any suggestions to up my HP?

[cobra400hp]

Fellow FE'ers, I have a '68 390 It is .030 over, MSD Distributor, 6AL box and Holley Projection. No head work or anything. I would like to get a little out of it. Can anyone give me some ideas to get a little more HP out of it?

Thanks

[Cobrabill]

What is your budget?

[Andy Dunn]

For any given engine size, here is where I consider the gains and size of the gains

BIG GAINS
1. heads
2. cam

both of these can add a pile of HP to an existing engine. Heads move the HP graph almost vertically and the cam can move it almost anywhere you want.

MEDIUM GAINS
3. exhaust
4. compression
5. manifold

compression certainly increases power...all the way up to 17:1. It's not a very pratcial method of gaining HP with an existing engine. Exhaust can add a solid amount of HP gains to an engine. a) Shorty headers to Full length headers.
b) 2" ID sidepipe muffler to 3" ID sidepipe muffler
c) regular headers to new stepped race headers

these all add HP...as much as 10% or more. A 454 engine with 500HP using small headers and mufflers will jump to 573HP when going to large stepped race headers.

going from a dual plane manifold to a single can add 5% or more HP. Adding a 1" carb spacer to the single plane adds more HP again. The taller than manifold, the higher the HP generally.

SMALL GAINS
6. carb
going up a size or two on carb can add a tiny bit HP. Most people have too much carb to begin with. Going from a dual plane manifold to a single will add HP, but not too much.

ACTUAL PARTS

HEADS
how about a set of PerformerRPM FE 6007
Performer RPM FE $1250
http://www.edelbrock.com/automotive/headford.html

CAM
how about a radical crane hydraulic roller cam for FE engines. 75-90HP over stock. Or a "serious" and "radical" performance solid roller at 70+HP over stock
http://www.cranecams.com/motorsports...ler/349541.htm
http://www.cranecams.com/motorsports/ford/343801.htm
http://www.cranecams.com/motorsports/ford/344621.htm

EXHAUST
Hoooker FE competition
http://www.holley.com/HiOctn/ProdLin...SHG/f6376.html

stepped race headers look more like this and you would most likely haev to get them custom bent at a custom header shop
http://www.holley.com/HiOctn/ProdLin...SHG/f2404.html

here is a nice site to calculate best header length for max power. Pick an RPM approx 200-400 over peak TQ for your engine and then you can see how long each header pipe should be
http://www.prestage.com/carmath/calc_headerlength.asp

MANIFOLD
Victor Performer FE or maybe even a crazy Victor but consult with an engine builder first on that unit.
http://www.edelbrock.com/automotive/man_ford_332.html

Edelbrick even sells a complete package for the 390 FE called the Performer Ford 390 c.i.d. Power Package
http://www.edelbrock.com/automotive/ford_2c.html

here are the gains over stock.
http://www.edelbrock.com/automotive/2105graph.html


hope this info is useful

Andy

[Jack21]

The January or February Street Rodder did some dyno work on a series of 390FE engine mods. One 434 stroker surprised everyone with what contemporary parts (roller cams, aluminum heads, etc) can do for these motors.

[Cobrabill]

And now for a disenting viewpoint...

Cam-Hydraulic flat-tappet with 1.7 rockers & Rhoads lifters can produce nearly the same power as a roller for a lot less money.FEs like a single pattern cam.

Headers-bigger is not nessecarily better.Especially on the street.
Tuned headers,stepped headers can actually hurt street performance.

Single plane manifolds make more power than dual?Not so.Depends where you want/need it.
Torkers&Victors tend to make more power in the higher rpm band.
An open plenum 1 inch spacer is good for 7-12 hp on a dual plane manifold.
Port matching is relatively easy and can result in a small gain for few $.

Recurve the distributor for correct advance&total timing.
What ever you do,do ONE thing at a time.You will be able to see exactly what improved,and if it gets worse-you'll know what to un-do.

[cobra400hp]

Thank You all for the suggestions.. this is alot of info to worl with.

Budget is small but I can do this over a period of time... The headers that I have are about as big as I can get.. I dont want to have to buy another set of side pipes.... I think a little head work and a cam will do nicely. I have the Holley PreJection so I can modify the air and fuel. THanks again for all your suggestions....
Paul