Hey guys,
I have an Edelbrock Performer Series 750cfm with electric choke on my 350. Basically what is happening is when I cold start it'll idle at about 1000 rpms in park and about 750 rpms in gear which is fine, but then after I drive around to operating temperature and put the car back in park the throttle revs up to about 1200 rpms which is driving me crazy. So I looked at the carb I noticed the Fast Idle Cam was keeping the throttle from returning to its starting position. What could be the possible causes of this? Its a new carb and I installed and adjusted according to the Edelbrock documentation. Could the electric choke be causing this or something binding?

Any help would be appreciated,
Thanks

 

Usually a little blip on the throttle will release it, and let the cam drop out, and lower the idle. If that's not happening, then the cam must be hanging up for some reason. Try just a quick hit on the throttle by hand, as you watch the carb, and see if you can see if it drops out. Might need a shot of some lightweight lube to free it up. Don't use anything heavy that might attract dirt.

 

Sometimes when its a cold start it will go a little high and that will work, but not after driving then putting it in park.. Thats why I was wondering if its the choke or something. What does putting it in park after driving actually do to the carb itself?

 

So I pushed the cam off of the screw and the idle drops extremely low ~200rpm. Does the fast idle set screw have to be on one of the "steps" of the fast idle cam at all times?

 

No. The fast idle screw is set to raise idle when the choke is closed. If it drops too low when it's off the fast idle cam, then you need to adjust the regular idle screw on the other side.

 

Ok thanks man, let me adjust the regular idle screw, then put the fast idle linkage back on the cam and adjust its screw. Im really not impressed with edelbrock on this, it feels real flimsy and its driving me crazy.

Ill report back tomorrow, thanks again

 

Make sure the choke is opening completely. If it isn't, the fast idle cam won't drop out of the way. Once the choke is open and fast idle cam swings clear of the choke linkage (shouldn't be touching), the idle is then adjusted by the curb idle screw on the drivers side of the carb.
Edit: Don't mess with the fast idle screw.....yet. Since it's obvious the fast idle linkage isn't moving out of the way fully as it should, another thing to try is to adjust the choke setting (round cover on the side) so that the choke isn't so tightly closed when cold. Sometimes you have to find a happy balance between what's considered closed and open.

 

So apparently the fast idle cam had never fully disengaged, so I manually pushed it off the choke linkage and set the regular idle back to normal and the car runs and drives perfect.

I then put the cam back on and it idled way high again, so I adjusted the fast idle screw down. That fixed that but still the cam wont step down! Should I just leave it off?

The choke is turned all the way to lean and its wide open.

 

You might want to do a check of the fast idle cam to see if it's dragging. Open the choke all the way, and then open the throttle a little. The cam should release and drop back to allow the idle to lower. If it doesn't, then check the travel to see if you feel anything restricting it from moving freely.
This can all be done with the engine off, or you can also turn the key on and wait to see the electric choke open after a few minutes. Then check the cam.

 

Have you adjusted the electric choke itself?