so recently i converted my 2bbl 1968 289 to a 4bbl
the combo i bought admittedly was a used edelbrock performer intake and 600cfm carb

intake swap was easy (thanks to this site)
carb went on
hooked up

started
just didnt want to run,
cough sputter venturi spewing fuel

reset floats recrank
fuel overflow fixed but now runs for a minute cuts off
recrank

over and over again

today i get up
totally fed up with everything
so i go to the local advance auto
and purchase a holley
hooked up
spun the engine a few times to fill the bowls
reconnected the coil and
damn it cranked right up
idle seems a little high out of the box
at 1000rpms but still

what a difference

 

Holley sucks. What size holley did you get? 600 cfm is big for a 289.

 

There are no carbs that perform 100 percent right out of the box. Obviously your old carb was in need of an overhaul, and the new one just needed some tweaking.

 

according to holleys application chart
all 289,302, and 351W require the 600 cfm
so that is what i went with



all i can say is even after a rebuild kit the edelbrock sucked and would not run

the holley fired right up, idled right at 800 rpms
no missing no surging

and after running for 10 minutes i pulled a plug and it was light brown

tells me its pretty close to be on

as soon as i get a chance to get it timed then take it for a drive we will see

 

Yeah, I have never had luck with edelbrocks. However, I have had good luck with Motorcraft carbs. The Holley is the second choice.

 

eh... My holley is a problem for me, Ive never had a crabed vehical and this is my first, Im having a hell of a time getting it right. Its a holley 600 cfm. I got it REBUILT, so that may be a problem, but i put it on and it was running WAY rich, enough to smell and see Black plugs. So i put diff jets in it, and will tune it next weekend and see how it goes. If that doesnt work, im going to advance and buying a new edelbrock 600 -Jon

 

Just get you a Motorcraft 4100 from ponycarbs,com and call it a day.

 

a) a 600 really isnt all too big for a 289/302 especially if you have any supporting upgrades.
b) its only 600cfm when the secondaries are all the way open, and lets face it.... how often is that happening
c) every nascar, and dragster runs holleys or holley clones...... i would guess they know engines and they pick holley for a reason
d) see answer c

 

A. I heard it is, at least all the calculators say around 470, so i wouldnt going higher then 500-550.
B. My secondaries are always open, but thats just me.
C. Holleys fail too easy for me, and i've had nothing but bad luck with them. I do know Holleys are run on most race cars, but that doesn't matter to me.

P.S. Like i've said before, you can get a 4100 for much cheaper at an Advance Auto Parts. It's a Champion rebuild, and they have been remanufacturing carbs for over 60 years or something like that.

 

Holleys are used on race cars, hence they rebuild/overhaul the engine after every run or every so often! -Jon