olds 307 and 403

There is one locally for $250 Canadian. What is their real world rpm range?

olds403

It is my favorite intake to run on a trans am. Will clear the shaker hood using a 400 drop base and 400 shaker.
They dont show up that often

olds 307 and 403

I agree. I am currently 4 plus hours away from home training for CN Rail. I will probably send my Wife to pick it up. Almost positive it is the SBO version.

cutlassefi

Depends on the engine size, heads, cam etc.

66-3X2 442

It was the intake of choice for Olds S/S racers.

olds 307 and 403

My 358 is around 9.5 to 1 with the 218/218 roller cam but I am planning on SEFI, as you know and new Edelbrock heads. What about a 9+ to 1 424 ci with an undetermined cam with aluminum heads? Even a ball park is fine. Just curious what this intake is like and where it starts making power?

bccan

I have been happy with Street Dom on my engine. Only downer is inability to open up the runners to anywhere near the BBO size, there’s no material there like Perf RPM. Someone on the forums had one that was welded up & possibly ported accordingly. It might have been “gr442” and he referred to it as the “Frankendominator.” It was quite some time ago & my memory is hazy, I only vaguely recall because I meant to see if I could buy it but never pursued it.

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olds 307 and 403

Thanks I assumed there was limited material for opening the ports from the picture of it. Almost nothing Oldsmobile, especially speed parts around here.

cutlassefi

Stick with the RPM.

olds403

If edelbrock would have made a SBO intake with enough material to run BBO olds heads and easily fit under the hood of a Trans am back in the day they would have done well. RPM of course is the obvious choice….just a PITA to get under the hood

71 OLDS

I'm running the HSD on my 374 build in my 70 Supreme and the lower height allows me to run the breather with no clearance issues. I'm running #6 heads not Ebrocks so can't speak to that. To answer the original question my motor runs strong up to 6,200. I've never gone past that but I assume it could probably go up to 6,500 with no issues. I'm also running a larger cam and Rhoads lifters. The car granny drives great and idles at 800 RPM smooth as glass. It feels like it has no power up to about 3,500 RPM and then all the power comes in. From 4k to 6k the car pulls strong.

bccan

Wow, I thought I was the only one that paints aluminum intakes! Maybe we should start a club.

71 OLDS

Haha nice! I like it!. I love that look. Did the same on my BBO in the 71 442 with the Torker:

olds 307 and 403

I painted the Performer to look stock when I put 350 in my 70S. It is currently held hostage at the machine shop. I also made that dual snorkel out of a 307 and 260 air cleaner. I will probably buy the Street Dominator intake. Glad to hear a real rpm range, kind of what I thought, being a single plane.