The 355 CC306 is together but when I am in first gear like coming to a stop sign or light the car dies. It will stay running if I gas it. What causes this? I had Ion tune it and I believe idle is 950rpm. Maybe IAC? with 52mm Holley...

 

If you can scan it you could probably see exactly what is causing the stalling. My guess would be IAC, but there's no for sure way to know unless you can see what's going on.

 

Have you figured out your problem? I just finished my 355 and CC306 Cam install and it's doing the same thing, it'll idle crappy, die occassionally, and is running pig rich all the time which I think is causing my stumble from running way to rich. This is what I have changed out when I rebuilt the motor 70 miles ago (Opti, plugs, wires, O2 sensors). I'm taking it to a shop tomorrow and have it scanned to see what's up, but if you figured yours out that might help me some. Sorry I also have a tune from Ion, I may have to send it back and see if something is wrong with it, but hopefully I'll find out more tomorrow. Thanks.

 

Have you adjusted the throttle set screw to get the IAC counts back into the proper range? After doing so, you will need to slot the TPS to get the voltage to ideal also. My car had issues with the fresh 383, and after we set the throttle set screw, and adjusted the TPS it hasn't had an issue since.

 

Boy you lost me on that one, I have no idea what you are talking about with the idle set screw and what not. Any help on this would be greatly appreciated. Thanks in advance.

 

Theres a throttle set screw on the rear drivers side of throttle body. If you screw it in it opens butterflies and if you back it out it closes butterflies. I turned mine in to keep butterflies open a bit and it fixed my problem. Hope this helps