Pontiac 389 - Suggested Intake Manifold
 

I’ve been kicking this around for a few days and would appreciate some suggestions/guidance. I have a freshly built 1965 389 .30 Over with a RA3 cam and 093 heads. What intake manifold would you guys go with? I’m considering an Edelbrock Performer or a stock cast iron 4bbl intake. Thoughts? Thanks All.

The factory intake is perfect for a street motor, I would suggest using a factory AFB too vs the Edelbrock carb. Read Carbking's website for more on that. My 389 made 400 hp 460 tq on the engine dyno with a factory intake and carb. https://www.thecarburetorshop.com/Po...market_AFB.htm

Do you have a carb yet, if so, which one?

Thanks for your response. I have a Holley 650 Double Pumper that I plan to use. Thoughts?

Thanks, I’ll take a look. Appreciate the help.

Carb is kinda small but, not that bad if the heads are not ported. If you do use that Holley, run the Performer.

i run a performer rpm, on my stock 65 389, butt dyno says it's got more pep than the stock one.

I've ran 4 carbs so far;
Factory Carter AFB-got the car started with it, then boxed it up and put it in storage.
Edelbrock AVS2 650cfm-felt like it was EFI, butt dyno and ears said it lacked on the top end.
Holley 4160 750-really woke up the motor, but in the end it was too much
Holley Street Avenger 570-Installed this one last weekend. Still tweeking it, but i will say this...in my 65 Bonnie, if i floor it...1st gear is useless, and for some reason my interior gets all smokey and smells like burning rubber!

Yep. Smaller carb keeping the velocity up with that big manifold.


My buddy runs a 340 Dodge A body. 230/236 cam with a T2 manifold. He runs a 650 DP. Starts easy and good throttle response. I put a 700DP on it. No tuning. The ease of starting went away. Too much manifold for his combo.

The heads are not ported. I also have a 700 DP I plan to rebuild in the event the 650 is too small. Thanks.

Lol. That's great. Thanks for the information.

The only thing a Performer will get you is weight saving over a factory intake.A P RPM will get you more performance.Tom

On my flow bench the Performer or a factory iron Q jet are the clear winners over a iron 389/421 AFB Intake.

The Performer is good up to about 415 hp, the factory 67 and up iron Q jet intake is even better.

The Performer RPM will by you nothing but some lost low end torque , not make you any more HP if your heads are stock and start to limit you from running a nice big stacked air cleaner !

My carb choice would be in the 650 to 750 range.

Oh, by the way if you have a stinky idle with no back smoke then your too lean, not too rich!

A factory tripower is also an excellent option. Easy to install, set up, and stone reliable. My '65 is running the original unit still without issue. 160k miles on it from new. Good mileage, resistant to fuel percolation, great visuals, and better performance than a stock AFB, although what the other gents said about stock 4V intakes and carbs is dead on as well.

I would run the Performer RPM intake... its a great all round intake.

SPEED SAFE, AIR RAM

Tri-Power.

The cool factor is off the charts.

Of course a four barrel runs just as well or better but.....Tri-Power is just so right.

Thanks Tom. Is the Performer RPM considered more of a high rise manifold? I'm concerned about factory hood clearance as well.

Thanks for the information. I also have an iron intake from my 69 GTO so I may just use that. Appreciate the help here.

I have a Tri-Power setup that was fully rebuilt by Mike Watson (Mike's Tripowers) several years ago which will eventually get installed after the body and paint is done. I hate to put it on before and see it get full of dust and etc. while in the bodyshop. Thanks.

Thanks.

I agree. Nothing like popping the hood and seeing that tripower. Thanks.