[slick1983]

What kind of hps will I get if if have a 400 .30 over with some keith black flat top pistons. What kind of heads should I use and what can you suggest on a cam and lifters and rockers for high hps?

[killerformula]

Originally posted by slick1983
What kind of hps will I get if if have a 400 .30 over with some keith black flat top pistons. What kind of heads should I use and what can you suggest on a cam and lifters and rockers for high hps?

anywhere between a little and quite a bit.

K

[k-star]

What is the intended use of this engine??? Dirt track racing, drag racing, truck pulling,,,, pump gas or race gas????

How much money do you have to spend on the heads and valve train???

What kind of car is it going in???

Keith

[spinn]

x

[MI2600]

With flattops, you'll have use 76cc heads otherwise your static compression is going to be around 11:1 and may put you out of range of pump gas. If you haven't purchased the pistons yet, I'd go with a slight dished piston (12cc) and a set of Vortec heads. That'll put you around 10:1.

I'd also select a lower rpm cam. The 400 is not a high winder.

[DoubleVision]

MI2600 tells the deal, 400`s aren`t revvers, and by all means, use 5.7 350 rods and not the 5.565 connecting rods that come stock in 400`s. You don`t need a lot of mods to make a 400 perform, you can use a few performance parts in a otherwise stock 400 and they`ll surprise you. whatever heads you get for it, make sure you have the steam holes drilled or you`ll have nothing but overheating problems.

[Siggy_Freud]

Double, is this something that needs to be done on all aftermarket heads? Aluminum and cast?

[Lonestar]

Steam holes are a must on all heads due the the proximity of the cylinders.

Personally, I have always clearanced the block and run 6" rods. It decreases the tangential angle on the crank and creates a little more efficiency.

[Siggy_Freud]

Understandable but do most or even any aftermarket heads come with this done already? Or do even the "complete" setups need work done (other than surface checking).

[Lonestar]

I have never bought a set of aftermarket heads so I couldn't tell you. I suppose you should check with their respective tech dept.

I have always just used the correct head gasket to mark the spots and drilled them out myself.

[tm454]

The heads MUST be 400sbc heads....nothing else will work properly...the steam hole thing is important!!


Tazz


Rat Rods Rule!

[Lonestar]

The water jackets in all the production heads are in the same location, so you can just drill out the steam holes.

I cannot verify aftermarket heads as I do not buy them.