starts and runs but doesnt stay running - carbed

[nicefighter80]

85 306 roller with edlebrock rpm intake(dual plane), holley 600 cfm carb with vacuum secondaires, MSD 6AL box and a msd cap, vacuum advance dist., gt40 heads, carter external fuel pump, 3/8(i think) braided steel fuel lines, stock serptine belt set up, i think thats all i can remember but feel free to ask
imhaving problems getting it to start but once it starts its not wanting to stay running, the carb, wires and plugs are brand new.

im thinking its the timing because when i threw the light on it, it was reading around 25 at 1500 rpms is that even right?

 

[nicefighter80]

i got it to run, but it has a off idle hesitation and im know sure why any ideas?

 

[DonMaximo]

Off-idle hesitation ?

Check your squirter on the carb...with the lack of info... can't really determine if you're coming in rich or lean and causing the hesitation.

 

[84Ttop]

Deffinatly sounds like a carb issue. What's your fuel pressure?

 

[nicefighter80]

FP is at 6 psi carb is a brand new holley 600 cfm vac sec. i think im leaning out but i didnt think i would lean out off idle could the timing be to retarded?

 

[84Ttop]

Has it done this since you installed the carb? I have seen a lot of problems w/ the new holley carbs. The menthanol they put in the fuel these days really eats at the coating on the metering blocks. If you pull the carb apart to clean it, you will find a ton of flaky material in side it. I would start there, and if that doesn't help maybe try a bigger squirter.

 

[nicefighter80]

well the carb is new like its never been on the road new it will idle fine but when you drive it, its got a bad hestitation till 2500 rpm im not sure why

 

[Celeb]

Turn the idle mixture screws all the way in and then back them out a turn and a half. Hook up a vacuum gauge and shoot for the highest vacuum at idle while adjusting the screws. Turn them both equal amounts, maybe a quarter turn at a time while checking vacuum.

 

[nicefighter80]

what will turning the idle screws do? not saying your wrong i just like to understand the concepts so i can help people trouble shoot on down the road