[sheerhavoc]

Hey guys I'm new to this forum.. I have a 1974 400 I was checking the head codes and I didn't find a match for them.. Anyway, I want to get some more horse out of this block and I need some suggestions.. My budget is around $2000-2500. Any suggestions??

[sheerhavoc]

Hey guys I'm new to this forum.. I have a 1974 400 I was checking the head codes and I didn't find a match for them.. Anyway, I want to get some more horse out of this block and I need some suggestions.. My budget is around $2000-2500. Any suggestions??

[Mr. P-Body]

There are almost as many formulas for making good power with the 400 as there are people building them. You need to touch the basic "bases". Intake, cam, exhaust, ignition and carb.
What is the purpose of the engine (car, gears, trans, etc.)?

[74gpman]

Depending on the use of the car, there are different ways to go. As Mr. p-body said there are many different formulas to making good power out of a 400. Since you indicated that you have a fairly limited budget, consider what needs done. If you are considering any signifigant power gains over stock (80+ hp), id suggest rebuilding the motor...adding big power to a worn out engine just spells disaster. also, remeber that certain mods like to be accompanied by others...an example would be a stout cam needs a good intake and exhaust to perform to the fullest.a great start for power is definatly intake and cam selection. Personally, I would not hesitate to recommend the edelbrock performer RPM package. this package has a good operating range (1500-6000). another bonus of this kit is that it is all dyno matched so you will know it will perform well right out of the box. Comp cam makes an excellent cam too! Since 2500 $ max is your budet the E-heads are not an option as they will eat up well over half of your $$$. I would guess that you have a 4x casting with 98 cc heads? (74 also had 46/4c, 89 cc small valve) if this was the case, you are only seeing low 8's as far as compression...this is FAR to low if performance is a priority, however choose accordingly. too high a compression is not practicle for street use ( id suggest staying around 9.5:1 compression for compatibility of pump gas.)Since there are few stock castings that will increase the 400's compression to a pump gas acceptable ratio (the early 72 cc heads make for a good choice however), a option may be to mill your current heads. This will allow for specific tuning...allowing you to in effect choose your combustion chamber volume. As always headers are an excellent!! choice to achieve high power. Now on a last note, I hate to be the one to say this, but if your engine needs a rebuild, i would highly doubt you will be able to go awefully fast on a 2000-2500 dollar budget, as machine work and new engine internals can run quite high...but this budget is do-able if you are smart about your selectins! most important to remember is that speed isnt cheap, and you get what you pay for...so choose WISELY!

[bmpmdf]

I would say a drive up to Mr. P-body would be the best bang for buck for you as his reputation is very good and he isn't terribly far from you.

[sardegna]

I just had a '74 400 block built, here's the general specs:

stock rotating assembly, balanced
Speedpro .030 over pistons, 10 cc dome (cr about 9.6), floating pins
4X heads, screw-in studs, 3 angle valve job, mild porting
Crane Energizer 272 (for good street manners)
Comp Magnum 1.52 rockers
Melling 60 psi oil pump


With machine work and parts i have about $2k in it. I haven't dyno'd it yet, but I can go sideways from a 20 mph roll. Car is a 1970 Firebird, Turbo 400 w/ 2300-2500 stall converter, 3.73 posi, 295/50's out back.


If you want a bulletproof, mega hp motor, go see Jim (mr p-body) at CVMS. He'll build you the best you can get.

[wk wood]

Sheerhavoc....Check out my post "H.P. gain on low compression 400". It is a mild combination, but would be inexpensive to duplicate and runs fine on low octane gas.