I have an engine Pontiac 400 stroked to a 461 have a edelbrock performer plus cam with edelbrock performer intake what size carb should I go with? I have edelbrock 650 now was on before stroked?

Edited January 14, 20251 yr by Jsain10
Add do

Hi Jsain10. I am going to assume that your motor is not an all out race motor, but rather a cruiser with some "spirited" driving from time to time. I am going to assume that redline for you is about 6500 rpm or less.

So a street carb - a 750 CFM carb would work well. If this were an all out race motor, then a 950 CFM carb would be the ticket. Since I am assuming a street carb - I recommend a 750 carb. 

If you think you will keep the engine under 5800 RPM, then your existing 650 carb would work.

Frosty's right. It's always tempting to over carb. If you look online, there are calculators & formulas for working out cfm requirements. Maintaining the correct stoichiometric ratio is key and you're rarely if ever going to need maximum cfm.

I found this, using my own engine as an example:

As you can see, my engine needs a piddling 450 cfm. Not enough to brag about to your friends but sensible enough to work properly.

Edited January 14, 20251 yr by Fitzy
Addition.

Have to agree with the guys...

The 650 CFM carburetor would will work fine on a street driven street engine that is normally operated...Off Idle to around  5000/5500 RPMs...

A 750 CFM...Carburetor  will work well also... Especially if you turn More than 5500 RPMS on a regular basis..But..You will have to play with the Jet sizes...In order for the Engine to Run efficiently throughout The entire RPM Range...

Two important things to Keep in mind...When Building/Tuning a really Stout Street Engine...

1)  Efficiency = Power..( Most Important )

2) Bigger is NOT always Better...( Cam/Carburetor...Etc...)

TLBT

Edited January 15, 20251 yr by TWO LANE BLACK TOP

You are sooo Going  to need to help me build this 400 for the 68 two lane !!!! 

Oh, hi. I'm still here. I mighn't be as knowledgeable as TwoLane but am a damn site closer! You're welcome.

1 hour ago, Fitzy said:

Oh, hi. I'm still here. I mighn't be as knowledgeable as TwoLane but am a damn site closer! You're welcome.

Aww 

i still love ya mate 😜

Aw look - it's a bro hug! Kiwi and Fitzy!