Need help with carb choice

[Albrainya]

Hey guys I need help choosing the correct size carb. I am normally a fuel injection guy, but the particular vehicle im putting my drivetrain into will not allow clearance for the efi plenum, so i am going to go with a carb. Heres my setup:
1993 5.0, stock bottom end, B-303 cam, thumper heads, 1.6 roller rockers,
dual plane intake,t-5 trans, 8.8 rear with 4.10 gears. The whole setup is going into a 2001 focus 3 door which i am converting to rear wheel drive.(see picture)
i was thinking maybe a 650cfm carb but im not sure since im not too familiar with choosing the correct size. In the picture you can see the gt40 intake that i was going to use, but the plenum will hit the cowl, so i cant do the fuel injection. Thanks for the help
Dan

 

[Xterminator03]

How To Calculate CFM:
Engine size (CID) x maximum RPM / 3456 = CFM
CFM @ 100% volumetric efficiency

(Example: 350 CID x 6000 RPM = 2,100,000 / 3456 = 608 CFM)


But I think a 650 Mechanical Secondary will be ok.

 

[Fishhawk]

Hey guys I need help choosing the correct size carb. I am normally a fuel injection guy, but the particular vehicle im putting my drivetrain into will not allow clearance for the efi plenum, so i am going to go with a carb. Heres my setup:
1993 5.0, stock bottom end, B-303 cam, thumper heads, 1.6 roller rockers,
dual plane intake,t-5 trans, 8.8 rear with 4.10 gears. The whole setup is going into a 2001 focus 3 door which i am converting to rear wheel drive.(see picture)
i was thinking maybe a 650cfm carb but im not sure since im not too familiar with choosing the correct size. In the picture you can see the gt40 intake that i was going to use, but the plenum will hit the cowl, so i cant do the fuel injection. Thanks for the help
Dan

The CFM calculator will tell you to go with a 600, but a 650 is definatly the way to go. Go to any NMRA event and with the excetion of the big inch small block guys they are all running 650's.