aluminum intake vs iron
 

Hi guy I am wanting to build a mild 428 engine with tripower. My question is how much of a difference performance wise is the aluminum intake over the factory iron. My tri-power unit is a 66 setup. I would like to be in the 600 hp range if possible.

Performance would be the same with either, both would require some extensive porting along with carburetor mods to supply the needs of a 600 horsepower engine.

Of course there would be a weight savings with the aluminum of around 15 to 20 pounds. A factory iron intake tips the scales at 38 pounds.

Mild 428 with 600 horsepower? A bit far away from mild I’d say. :)

I say mild compared to what most people are running with twin turbos etc. Do you know anyone that does that kind of work to tripowers or am I just pissing in the wind lol

The end carbs would need to be opened up for the added flow needed as a starting point.

Maybe one of our forum members and Tri-Power experts Dick Boneske could handle the carburetor work or advise on who could do it. Intake porting I’m not sure but shouldn’t be hard to find someone in the Pontiac head and intake porting business to handle it.

ok thank you sir.

aluminum intake will work better if you need to open intake ports to match heads i just built a 461 with eheads we welded intake so it would match ports in head

Go with the factory iron one. The aluminum intakes aren't no where near as straight as the factory intakes.
Too much core shift.

I sent at least 2 aluminum intakes back before I found a decent one to have ported.

Just make sure the factory iron intake isn't cracked.

Has anyone seen or gotten their hands on Dave Wilcox's tripower intake he is advertising?

You might check out FiTech's tripower EFI setup. I remember reading about how much harder it is to get good, even fuel delivery with the tripower setups so this might take some of the hassle out and get you closer to your 600hp goal. FWIW, I'm building a pretty typical 461 (400 stroker) with an Edelbrock RPM intake and the Speedmaster heads and don't expect to hit 600hp, more like 500 and change. Getting 600hp out of a 428 and likely more restrictive intake would be tough.

How do you like the speedmaster heads?

They got caught up in Coronavirus delays.

When I ordered, they let me know they were waiting on blanks for them to machine, I wasnt in a hurry so said no problem and placed the order-- but I guess their supplier has stopped sending shipments for now. They were expected mid-March but they're saying end of May now. Good customer service, though.

If that's the biggest impact I have from Coronavirus, I'll be a lucky man.

Does anyone know if it is possible to cut the exhaust crossover out of a cast iron 66 intake?

I don't have a good picture of it, but I think you can see it here. I would not recommend it. It's a lot of work, and the cold performance is not good. My reason to do it was to have port injected nitrous, but they would not do it on a cast iron manifold.

This is the picture I was looking for and couldn't find.

I've got one like that, too. The heat riser passage was removed and the dividers between the left and right runners were machined out. It was ported to match the 722 heads. Dan Whitmore used it on Glory Days '65 GTO. The car ran mid 10's in the '80's with that manifold.

The car had 722 RAIV heads, 455 .040 overbore, healthy flat tappet cam.

I think he could have gotten more out of it with some work on the end carbs. He did remove the air cleaner webs from the airhorns. But, the venturis can be machined to about 1.420" from the stock 1.312". Dan did not do that.

Yes thats it did you do it yourself Jim? what did you have to do to clost it back up?

Yes, I did it myself. I used drills and a cut off wheel. Although my heads are welded up, something needs to be there to support the intake manifold bolts. I used some aluminum bar stock and had it cut to fit.

Malgotech
 

This is MALGOTECH father of GLORY Days 10.5 inch tire
3500 with driver DAN WASWAY AHEAD OF HIS TIME, IF ANYONE EVER SEES THIS PLEASE MESSAGE ME. I WANT IT BACK. IT WOULD EASILY GONE MID NINES IN GLORY DAYS