Pontiac Big Chief intake question

[nosnerd]

spiros motor had EPD 420s .....his motors were getting smaller and smaller by the mid late 90s.....from 540cis down to low 420s....he tried three combos iirc back then...


alan

[Adger Smith]

I believe the Pontiac head was an original spread port design by Lee Shepherd that Brodix ended up casting. I have had 2 versions. A 427 casting number that was a 18 deg and I now have a 386 casting number that is a 15 deg. There was a cast intake for them. Seems like Edelbrock did it. (I would like to have one) The Big Chief/Big Duke heads have a different port spread and their intakes don't fit. I have a Dart Big Chief intake I tried (I'll sell it). They had bigger chambers than the newer design Duke/Chief heads. I've been told they make good NOS heads.

[nosnerd]

To clarify my previous statement, the Brodix "Pontiac" version of heads I have seen that are straight-out-of-the-box, unmolested heads do have siamesed intake ports, not spreadports. A friend of mine has a set, I'll see if I can post some pic's if I can get over to see them. Those heads in that original photo ARE Pontiac heads, you can tell from the scalloped out areas above the exhaust ports. I also remember seeing Spiro's car run with that engine combination in NMCA Super Street back in 1994-95. Chuck Samuels at Fast Times Motorworks was building his engines then. I believe that intake you have there is for the non-spreadport versions of the Pontiac head. I recall an article several years ago where someone was running a 470-ish engine in Super Street in an orange 1969 Camaro that had one of those intakes on it. The story writer stated it was a "very rare" Edelbrock manifold for Pontiac heads. It too had siamesed intake ports. Not trying to be an a-hole, but I know what I know and I've seen what I've seen. If I can get some pic's of those unported Pontiac heads my buddy has, I'll prove it.

you are thinking of duanne waldrop..i had asked around at the time about that rare eddy intake..it was over 1000$ at the time..



i took this pic in the S/S pics at memphis FSC 96....man the carnage there!!

[RowdyRed]

Hi there, I'm new to the board and realize this is an old post but was hoping someone could answer a few questions for me. I have an old 632 with what I was told are Pontiac Big Chief heads. The heads are both stamped "Pontiac". One is numbered 10093385 and the other 10093386. Long story short, I'm trying to find intake gaskets and was wondering if anyone knows which are the correct ones? I have some gasket material and can make the gaskets if need be, but I was hoping to figure out if there are any still produced that would fit right on there. The other thing I'm wondering is if anyone happens to know anything about the exhaust flange angle on these heads. I'm trying to run vertical headers which previously fit on a stock BBC but I'm not sure of the difference in angle between the two? Are the Big Chief 10093385 and 10093386 heads 15 degrees?
Thanks in advance for any info you can give me!

[shoedoos]

00R0R_eOUU0V9xISr_1200x900.jpg

Just dragging this up again because I spotted this in a craigslist advert......anybody know who made the intake adapters? In the advert it said Meaux has something to do with the heads...

01313_bvJIx2akFVz_1200x900.jpg

[Frankshaft]

spiros motor had EPD 420s .....his motors were getting smaller and smaller by the mid late 90s.....from 540cis down to low 420s....he tried three combos iirc back then...


alan

Any idea why? I will tell you, lol. Its a heads up lb/cube deal. And, the smaller engine with the same parts otherwise, runs way more rpm, and he can be lighter, another advantage. What happened? He went faster and faster. I wonder if anyone will get the correlation.

[Adger Smith]

The adapters are probably hand built by someone. they are adapting a non spread port manifold to Spread port heads.
The 385/386 heads are made as 18 degree.
It is common to mill them to 15 deg.
The odd numbers were because one head came as a blank head, no seats and guides the other came with seats & guides.
I can't remember which was which, but I'm thinking the 385 was the finished head.
They are the same as the 427 head with the exception of original port runner size.
The 427 came with bigger port runner volume.
Depending on who did the chambers they are usually very NOS friendly.
The plug location is also very good for less timing and the piston dome is usually small.
Back in the day I did quite a few engines with those heads.
I still have one bare set of the 385's.
Don't sell those heads short.
There are more modern better heads, but those are still pretty good.
The adapters and intake are probably the weak area of what I see in the picture.
A Big Chief/Big Duke intake can be modified to fit & might be better than the adapters.
You might give the guys at Profiler a call about an intake.

[FC-Pilot]

00R0R_eOUU0V9xISr_1200x900.jpg

Just dragging this up again because I spotted this in a craigslist advert......anybody know who made the intake adapters? In the advert it said Meaux has something to do with the heads...01313_bvJIx2akFVz_1200x900.jpg

Looking at the picture there are a number of unique modifications to that setup. The water outlets, the welded in rocker stand spacers and a few other things besides the intake setup. Adger is right, that intake setup is probably limiting its potential. I have had my hands on four or five sets of those heads and they all made good power. Yes there are better heads out there these days, but if they are not beat to death and are complete they can be a really good bang for the buck.

Here was my favorite engine we built with them. I loved the stack injectors on it.


Paul

[smlblk_ron]

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