Stage 2 alum. head??

[NCTURBOS]

Are there multiple casting #'s to these heads? How does someone know they are purchasing a "good" set of these heads?

The reason I ask is because one time when at Dave Weber's I was comparing one of Terry Houston's heads to another one there at the shop. Terry's intake port had a better angle to the valve than the other head. Both the roof and the floor of the runners were higher. This appeared to be in the casting and not done by a head porter. If the roof of the runner on the other head would have been ported to match Terry's it would have been so close to the underside of the valve spring pad it would have been too thin, and maybe break through.

I guess what I'm asking is, what should I be looking for in a set of Stage 2 heads?

Also, am I correct in saying that the only "downside" to these heads would be some drivability? Are there any mechanical failures associated with these heads?

Thanks In Advance,

Keith

 

[Mac in SD]

I'm not sure I can help you with early and late casting numbers, but I can tell you that later castings had higher ports.

On the driveability question: THEY'RE GREAT, and don't let anyone tell you otherwise. Of course, the assumption is that you'll have a 3300-3500 stall 9-inch type torque converter. The thing is, you can't go very big on the cam...mine's a 222/218 hydraulic roller. When flow goes up, you can cut down on duration. I've got a 274-inch motor with S2 heads (2.125 intake / 1.625 exh) and a 62-1 turbo (temporary - T76 BB on the way), and I can light the tires at will. Plus, no cracks! Don't buy the old chestnut about S2 heads not working on the street.

 

[turbodave231]

The Buick Stage II V6 Racing Engine booklet by D. Emanuel talks about changes that were made to the 25500030 aluminum head.

" The most recent version of the Stage II head features a recontoured combustion chamber, additional bosses for mounting multi-shaft rocker arm assemblies, rocker gasket surface raised .150" compared to earlier versions and the intake port roof raised .100". "

So it looks to me like not all Stage II heads are created equal.

Dave

 

[NCTURBOS]

Dave,

Where is this booklet available from?

 

[KendallF]

I ordered that book from Barnes and Noble online; it's short but useful. I have a set of brand new early S2 aluminum heads, and a set of later castings. The later castings have the port roof raised, and what I'll call the "swirl ridge" between the valves is more pronounced on the later castings. They are the same casting number.

I was at Duttweiler's last week for part of a day and he had some revised-yet-again castings that featured a tall boss for the upper "extra" 3 bolts and some other changes. They had a Buick Motorsports casting number but I don't know what it was..

Talking with Ken about head design, he mentioned that the Indy square port head was a very good design for high HP and that Gallina's car has these on it now...I found that pretty interesting.

Ken and his wife were super nice as usual and put up with me hanging around and picking his brain for tips.

 

[NCTURBOS]

Barnes & Noble...

I just checked their online site. I didn't find anything by author or keyword!!??

 

[turbodave231]

If you can't find a copy I could scan it and email it piece by piece.
We should get Ken Mosher to post it on the "other " GN website.
Good reading.

DR

 

[KendallF]

This ought to bring it up...looks like it's unavailable now tho. Keep the ISBN around and search the used book sites; you'll probably find one.

http://search.barnesandnoble.com/booksearch/isbnInquiry.asp?userid=527BJ614K5&isbn=0942099001