Anyone who has worked on the Bulldogs know they have a huge blob cast around the guide which isnt necessary and the guide protrudes way to far into the bowl area. its way deeper than it needs to be , to the point the undercut area of the supplied valves is up into the guide more than .175" when the valve is closed. this really kills the intake flow on such a nice raised port head..i have no idea why they did this.

thought i would post some pics on what to do as a fix and pick up about 50 CFM

the guide length is 2.350" which is way to deep into the bowl. I cut the back .350" and also install Kline bronze inserts as every Bulldog head ive seen has poorly honed guides that are very loose at the ends compared to the center. they still flow 290 to 295 with a 2.150" as they come.

installing a 2.250" valve with a much taller undercut area on the stem to take advantage of shortening the guide back .350" the stock valve undercut stem height is 1.475" from the valve face, the 2.250" valve has a 1.610" , this is why the guide can be shortened quite a bit(2.00" final length) and still offer enough support. the intake will flow close to 350cfm with this work alone and no upstream port work,,leaving it as cast. raising the roof right from the guide all the way to the manifold face will get you 380,, widening the bowl and walls to the max , its possible to see 395 to 400

 

I had a customer bring in a set of Bulldogs recently. Biggest piles of crap I've ever seen. Visible porosity on nearly every machined surface, rocker stud holes pulled out etc. Thankfully I was able to talk him into going a different direction.

 

What's a Bulldog head? I thought the Olds heads never made it to market? I remember Caddy heads, but thought the Olds were just prototypes.

 

must have been one of the first sets.

they did have casting problems on the early ones. Of the three sets I’ve had through my shop, all get pressure tested. They were fine, just like this set.

the casting and machining is very good on all the ones I’ve seen… except guide honing

 

they did get made. I’ve had three sets i worked on.

dont know how many total

 

They have a few nice things going for them.

the intake surface of the head is plus .140” over a stock head, which raises up the intake.

the roof of the intake port can be raised .800”

a D shaped ex port that exits a lot higher with stock bolt pattern

Factory intake port layout

 

 

Wasn't there two versions? I thought there was a street and race version. This sounds like the race version, going off the old magazine article and the claimed number. You probably had 3 more in hand than nearly everybody in the Olds world. Terry Fritsch bought them off Bulldog I believe or so he said and continued their tradition of taking money without delivering heads. They looked pretty promising, too bad.

 

.......and, then, didn't Wise buy the molds when Fritch went bankrupt? That's where they died, I believe.

 

No, I think Wise was a whole new Con job. Mark(Cutlassefi) dealt with him, man to man, it ended with Wise pulling his usual BS. Wise's heads on a SBO required a big block intake, the BBO, spacers. I saw Terry trying to peddle the former Bulldog's somewhere just a couple of years back, long after Wise started.

 

Huh.
Nothing like a good head thread for the winter.

 

The Bulldogs and the Z do have a lot of similarities.

here’s a few shots of the Z heads used on our 2019 Race Engine Challenge piece.

notice the exhaust exit height and shape is the same. The port all the way though, same.

the port in the Bdog can go up to the height of the Z if you wanted.

Z ex and intake face. The head height, width and length are the same. So to me, the Z was a Bdog with changes made to raise the intake port. The combustion chamber is quite a bit different between the two. Z very compact and a better design

these went 400 at max lift

 

The Wise head is basically a reconfigured SB2 head. I believe Dick Miller was a dealer for the Bulldog stuff for awhile.

 

I know unWise was peddling the SB2 thing when these first came out. i think that was his sales pitch...they aren't anything like it

the SB2 intake has a semi rectangular port, the valves are rotated in the chamber , int angle is 11deg with a 4 deg cant, the two inner ports go through the pushrods, not around the outside of the intake p rod like Olds. the SB2 is a semi symetrical/mirror intake port layout,,,both outer ports are identical to each other while also being a mirror image of the other two. none of that stuff is in the Z heads,,,,it couldnt be if he wanted.

the ex is even less similar

 

I only know of two in the beginning. a small port one for small blocks(min CS 2.50 sq") and the big port version. there may have been a CNC ported one later on?

 

Very cool you get to work on these. So little info on them, thanks for sharing the info and pics.

 

These are going on a Rocket Racing block in the neighborhood of 535”

ill post the progress of the build..I’m only doing some head work..the owner is finishing off the rest of the head work and engine.

it’s going in a 70 W30 post car which will use all the original cold air induction and hood. So it’s going to be a challenge to fit these tall heads and an intake under the factory hood.

Pump gas

 

Dale, more specifically I was told that DIMENSIONALLY, the EXTERIOR was closer to an SB2 than any other raw casting. Sorry for the discrepancy.

 

sounds cool!

 

I think this guys son's YouTube channel is Mod Everything. He was Twin Turbo Charging an Olds 260 and they discussed this build on that channel. I really don't why they don't let Dale finish these heads, he is obviously capable. Hopefully, the guy knows what he is doing and doesn't wreck your work. A Rocket Racing Block build is going to cost a fortune no matter what, proper head work is key to feed that beast.