OK I'm building a motor for a buddy. He bought this motor all machined and ready to put together.

The heads are used Victor Jr's with mild porting. Problem is they only have the "easy" steam hole drilled in them...

Anybody have an opinion about this?

The car will be driven on the street even though the compression is 10.55 to 1.

I have searched and found no help on this one.

Thanks,
Ernie

 

All the steam holes will need to be drilled in the heads or it will overheat.

Use a 400 head gasket as a template and drill 1/4" holes.

 

I was told 1/8" holes. Wich one is it Steve?

 

Look at a factory 400 head or headgasket. It has 1/4" holes. Why would you want to restrict coolent flow through a tiny 1/8" hole and risk overheating the engine?

 

Doesn't matter what size, as long as they're there. I usually use 3/16" myself.

They're all equally easy... it's 6 holes in the deck surface. Like Stephen said, use a head gasket, mark them with a center punch, and drill. i'd be surprised if both heads took more than 10 minutes to do.

 

Before you go drilling those holes make a call to edelbrock I have heard of heads not having a water jacket for those steam holes to be drilled to. Make sure these aren't a set. The method for the drilling I use is i put a 400 gasket on the head (old one works) line up the stud holes using tight fitting bolts to drop in the bolt holes to hold it still and center punch all the holes. The holes nearest intake side of the head(closest to a stud hole) need to be drilled at 30 degree angle toward the exhaust side. The other 3 go straight down. All of this is considering you call Edelbrock and confirm that it will accept them all!



Actually on all the 400's I've seen and built they are different sizes 3/16 on 1 row and 1/8 on the other row. I have always used an 1/8 inch bit.

 

Thanks for all the feedback guys.

I have e-mailed edelbrock for their input.

Here's what I've got:

http://community.webshots.com/photo/...47236806lEljnK

Thanks Again!



Ernie

 

I have a 400SBC with NO steal holes drilled. The car stays at 180 in 107 degree weather here in Nevada. I'd say the steam holes arent absolutely necessary if you have a half way adequate cooling system.

 

Ok I have the "final answer".

Per this e-mail from Edelbrock:

"For street use, you would want to drill the 3 steam holes on the exhaust side (or lower) of the head only. For race only use, especially drag racing, one steam hole would be plenty.

RS"

I also sopke with the guy that sold my buddy this engine and he said that's the way edelbrock said to drill these heads.

They are going on as is.

Thanks for the help everybody!

Ernie