BigE

iTrader: (2)

I'm relatively new to carbs as I have only messed with fuel injected vehicles. However, my father has a 1986 Trans Am with a 305 that has been converted to a stand alone carb setup (as opposed to the electronic carb or whatever the factory stuff was). He bought the car with an Edelbrock Performer intake and an Edelbrock (Weber) carb already installed and running. However, the throttle shaft was worn leading to some drivability issues and he wanted a Holley so I got him an 80570 Street Avenger per Holley's recommendation. Long story short, we removed the running Edelbrock carb and installed the Holley. Pumped the throttle and fired it. She started right up but wouldn't idle. She won't start unless you give a little throttle and it won't stay running unless the throttle is slightly pressed. Holley touts this carb as being preset and extremely close out of the box. They have several adjustment procedures listed, but I don't want to go trying them all without some sort of direction. Should I adjust the idle screw, the idle mixture screws, the choke position, fast idle screw or ?

Thanks all!

P.S. They also neglected to mention they don't make a bracket for the cruise control cable. Gotta figure that one out, too. Not to mention the trans is making noise. But carbs are simple, right?

1 FMF

iTrader: (1)

on the trottle bracket, the side of the carb that the throttle cable attaches, there is an idle stop screw. Or, if you disconnect the throttle cable and manually open the throttle on the carb then release it the spring pressure closing the throttle will stop when it hits the idle stop screw. Turn this screw clockwise (inwards) 1-2 turns to raise the idle, and it should let the engine idle without having to touch the gas pedal or anything, or even have the throttle cable attached to the carb. Once the engine is running for 5 minutes and is warm, and the choke is fully open, you can adjust this idle stop screw to get the idle at 700-800 rpm. Don't turn any other mixture screws, the carb should work right out of the box.

Other thing to check is make sure the electric choke is connected, and you may have to adjust the choke mechanism. lot of times the choke will be too much and the engine will stumble for the first minute until the choke heater opens the choke.

ZONES89RS

iTrader: (25)

Just up the idle screw till it will idle at your desired RPM. Then make sure you have it timed so it fires up instantly if you have been messing with the timing at all. Carbs are VERRY simple and they are screw driver friendly, i cannot figgure out where a lap top plugs in but i manage. From there it should be as stated from the factory, within ajustment.

BigE

iTrader: (2)

Thanks, guys! I'll give it a try. Is the curb idle speed screw not set from the factory or was mine just too low for my application?

ZONES89RS

iTrader: (25)

Well, count how many turns it goes in, if it is less than 2 then you can go 2 turns out completly and see what that does for you.