[randyjrc123]

Wouls a set of 624's 1.94+1.50 make a 400 "weak" or what heads would be recomended for the street. looking for less than about 500$

[Rogers Performance]

The 624s and 416 heads are none for cracking so be careful what you by. I would look for some older castings that are thicker or put on some after market heads.





mike

[Jmark]

Head selection depends a lot on the entire engine parts selection and what you want the engine to do.

For a good low to mid torque engine, stock heads with those valves will be good on a budget. If you need more hp in the upper rpm range, then you need to get heads with bigger runners and bigger valves.

You can drill the extra water holes in any sbc head so they will work on the 400, its no biggie!

Mark

[NAIRB]

Originally posted by randyjrc123
Wouls a set of 624's 1.94+1.50 make a 400 "weak" or what heads would be recomended for the street. looking for less than about 500$

The 624 head is pretty much like the stock 400 heads. The 624 head is a lightweight casting and crack-prone. You can use these if you want but I definitely would not consider them for anything other than a stock, budget type of rebuild. I would not sink alot of dough into 624 heads. The more preferred stock open chamber type heads will be the 441, 493 and 993 head. The 882 head is plentiful but the casting is lighter than the 3 above mentioned heads. You can expect similar performance from all of the heads mentioned as their designs are all very similar or identical.

[randyjrc123]

What price will I be looking at for a good set of heads that are ready for install. I definately do not want a set that is crack prone.

[Rogers Performance]

when i do stock heads for a customer i throw every thing away except the retainers and put all new parts in rebuilt small block chevy $350.00 for a set

[randyjrc123]

what about the 461's are these the double hump heads? and are they any better than the 441, 493, 993's?

[NAIRB]

The 461, or any other "double hump" type casting are superior to the open chamber heads in terms of combustion efficiency. The compact chamber of the 461,462,291,186,492 and 041 head will yield more power, all other factors being equal than a comparable open chamber type head. Generally speaking, a good 20 horsepower over it's smogged out counterpart.

The bad part, as far as your 400 is concerned, is that if you use the early 64 CC heads on your 400, you will push the compression ratio beyond the realm of pump gasoline. You will have to use a seriously dished piston to maintain a streetable compression ratio.

[coldknock]

No joke NAIRB. I had to use pistons with a 18cc d-shaped recess to get it down to 10.17-1 on mine. Kieth Black pn.147.

[randyjrc123]

So what heads should I use where I do not have to use jet fuel..remember I want this for the street and I will be putting it in a restored short bed 67-72 truck. Should I stick to a 76cc head? or again what head should I use for this progect within reason...

This is just project and will not be used for racing by any means. Just a fun engine in a restored vehicle. Whith that in mind if I used a set of 462's or large chamber heads will I be able to use pump fuel?

[camaro409]

Look on ebay you can get a set of dart iron eagles for like 500 bucks brand new...the non blems too

[lluciano77]

Originally posted by NAIRB
The 461, or any other "double hump" type casting are superior to the open chamber heads in terms of combustion efficiency. The compact chamber of the 461,462,291,186,492 and 041 head will yield more power, all other factors being equal than a comparable open chamber type head. Generally speaking, a good 20 horsepower over it's smogged out counterpart.

The bad part, as far as your 400 is concerned, is that if you use the early 64 CC heads on your 400, you will push the compression ratio beyond the realm of pump gasoline. You will have to use a seriously dished piston to maintain a streetable compression ratio.

I have 64cc Sportsman II heads on my SBC 400. I have Keith Black flat top pistons. My ratio is at 11:1. With a little prep work and planning, I am running 91 octane with no problems.

Originally posted by camaro409
Look on ebay you can get a set of dart iron eagles for like 500 bucks brand new...the non blems too

That would be the smartest thing to do. Keep your eyes open. Sometimes you can get a good deal on AFRs or Trick Flows, etc., but the Darts are always there.

Aftermarket heads are almost always the way to go.

[NAIRB]

Leading someone to believe that you can run 91 octane fuel with a true 11.0:1 compression ratio is probably unwise. Maybe by some freakish combination, you are doing it, but most people will experience engine destroying detonation problems with this much compression on pump fuel. Of course, this has been discussed in depth in many, many threads and probably should not be rehashed in this particular thread.

[machine shop tom]

Many of the 461 style heads that came with 1.94"/1.50" valves have chambers that measure around 60cc's or less.

I know I've said this before, but it's a good idea to take new heads to a machine shop to have them checked out. More often than not they need valve work and resurfacing.