Better Q-Jet for 403 performance?

[1979SE]

I have a '79 403 with a rebuilt Quadrajet, casting number 17059253, which I've pretty much decoded.  (Not sure about that last digit though, as my car is an automatic.)

The car is a dog.  Compared to other 403 engines, it is a dog.  Compared to my grandmother's scooter, it is a dog.  I've read that a stud on this unit was placed to limit the butterfly and restrict fuel delivery.  Any truth to that, and is there a fix?

Also, is there a Quadrajet (1975 - 1979) that offers better performance on the 403 engine (AT)?

Thanks much!

[77cruiser]

Have you done a tune up? Checked the timing advance curve?

[carmantx]

yea, what cruiser said, first.
"rebuilt" is a broad statement.  What parts and who built it.  Very possibly, built with junk parts and not tuned to your engine.
Get parts from Cliff if you are going to build it and get his book so you can learn all of the ways to make it work best.

[1979SE]

Those are good points and something I hope to learn more about here.  The carb was rebuilt by Holley, but I seriously doubt it was tuned for this engine.  Being a '79, I'm also concerned with mechanical limitations the carb may have had to appease new EPA regs.  I have ordered Cliff's book and look forward to digging in -

[429bbf]

i had a dog one time (1979 ford 400 in an f250 )i still have the pickup . it was so bad you had to put it in 4 low to climb a hill it would run out of power . it also got 5 mpg on a good day.( i bought it new) it had 2 problems i, carburation ,2 timing  they retarded the cam about 8 degrees from the factory, and the intake system was garbage . i changed the timing chain, installed a 4 barrel manifold and a quadrajet. the quad was from a worn out 350 chevy that you could throw a dog past the throttle shaft and it still ran 10 times better and got twice the fuel milage.fwiw

[1979SE]

i had a dog one time (1979 ford 400 in an f250 )i still have the pickup . it was so bad you had to put it in 4 low to climb a hill it would run out of power . it also got 5 mpg on a good day.( i bought it new) it had 2 problems i, carburation ,2 timing  they retarded the cam about 8 degrees from the factory, and the intake system was garbage . i changed the timing chain, installed a 4 barrel manifold and a quadrajet. the quad was from a worn out 350 chevy that you could throw a dog past the throttle shaft and it still ran 10 times better and got twice the fuel milage.fwiw

I'm hoping carburation is one of my problems.  I know my intake manifold is garbage, too, and am looking at an Edelbrock Performer to help with that.  I feel pretty good about the timing, but will take another look at it.

[428goat]

Got a clean 17058253 for sale if you are interested. Linkage free & no binding.
Rich

[1979SE]

Got a clean 17058253 for sale if you are interested. Linkage free & no binding.
Rich

Maybe so, Rich, thanks.  I messaged Cliff my specs to see if he may be able to breathe any life into my Q-Jet.  May want to pick up a unit for him to work on - will PM when I hear back.