[Jimmy Sester]

I'm getting ready to switch my 2 barrell over to 4 Barrell on my 76 Grand Prix with the 400 in it. Just looking for suggestions on what intake and carburetor I should use.

 

[75gmck25]

It depends on your budget and your performance goal. A good dual-plane intake and a carburetor in the 650 cfm range (maybe bigger on a 400?) is a typical setup.

I assume they make an Edelbrock Performer intake for your engine, and it’s a frequent dual-plane budget choice. The Edelbrock RPM intake is a step up in performance. The Edelbrock AVS2 carburetor usually works great right out of the box on a street vehicle. However, you will find many guys who love the performance tuning options you get with a Holley. Quadrajets are also still popular, and may have been the OEM carburetor on your car, but it’s often a love/hate choice.

 

[BrianB74SD]

Since you are simply switching from a 2 barrel to a 4 barrel, stock Pontiac cast iron 4 barrel intakes flow very well and a way to save money. Check out the input on the net from the various Pontiac supporters. Depending upon on your mechanical confidence level, topping it off with a well sorted Quadrajet wouldn't be a bad move either. Make sure the primary throttle shafts are not worn to the extent that cause vacuum leaks. You will very likely need to address the idle circuit too when setting up your primary and secondary jetting and rodding. Armed with a little knowledge, you can do it.

 

[idrivejunk]

I am a long term Pontiac V8 user. If you want simple and effective and it is stock:

Plain Edelbrock Performer intake, plain Edelbrock Performer carb. A 750. You won't have to tune it or use a fuel pressure regulator. Despite all those performer words, it still won't be much of one but you can expect lots more fun with a four barrel.