gooser

289 engine, 2 barrel.motorcaft i think. what was the airflow from the factory? (in todays terms) anyone got a clue?

kalli

300cfm at 3"HG if it has the 1.08 venturi (see stamping at the side)

Kalli

gooser

thanks. so a 390 4v may be a suitable replacement? (stock camshaft, exhaust manifold, single line exhaust) edelbrock performer aluminum intake however.

67mustang302

The key is at 3" of hg. Whoever's retarded idea it was to flow 2bbl and 4bbl carbs at different depressions I'll never know. Converted to 4bbl flow(1.5") that 300cfm is more like 215.

67mustang302

390 4v are decent carbs for a stock engine like that. It depends on what you want from it and what you're willing to spend.

gooser

what do i want from it? reliabilty, smooth idle, driveability at low and mid engine speeds, QUIETNESS, throttle response and cheap. i already have the parts mentioned.


just about the opposite as most posters around here want. not interested in high end horsepower.

67mustang302

Well, the NASCAR Busch guys are running 358" engines at 6,500rpm with 9.5:1 compression and make 500+hp breathing through a 390cfm carb. Even small carbs can make big power, but it will run great on the street on a stockish engine. It'll give you everything you want for low cost.

my77stang

i don't care what anyone else here says, a 390 is way to small for a stock small block V8. a holley 4160 600cfm will work excellent in stock form on a stock motor, and if your really concerned about going too big (which the 600 isnt) a 500 carter or a 525 barry grant would do you just fine.

remember kiddies, even the motorcrafts were 450

67mustang302

It all depends on how the carb is set up. I can garuntee you that a Busch tuned 390 NASCAR carb will outperform 90% or more of the larger carbs most people are running. The metering circuit will have a bigger effect on power than the size will. In the end though, a stock 390 4bbl is fine on a stockish 289 that's prolly only making a real 180-190hp.

1971mach1

Why not another 2 barrel ??, That will give you all your parameters. The 4 barrel
is the opposite of what you want, more expensive, louder, maybe less reliable with more moving parts, worse MPGs.
That said, I really like my Edelbrock carb for no-fuss reliability.
BTW, quietness has alot to do with your air cleaner housing. The stock
snorkle types are much quieter.