Well, ever since I rebuilt the TPI 305 in my IROC, it's been running well, but have struggled with timing ever since. I read an artice on the TBI equipped "My Generation" Camaro in this month's CHP, and basically read "initial timing is set like any other 80's computer controlled car, unplug the 4-wire harness to the HEI distributor, set the timing, then hook it back up". So I was relieved to read this, until I tried it... It won't fire with that plug disconnected! So what do I do? Something is way funky with my timing, I don't think my balancer and my tab are lining up correctly either (both seperate aftermarket... sheesh) because when I try to set the mark on the balancer to line up with anywhere between 0-15deg on the tab, it runs crappy and wants to die when given any throttle, but when the mark is WAY outside of the tab it runs well, it's basically come down to timing it by throttle response. The only problem with this is that there's always a "hole" in the RPM power-band where it runs rough. All aspects of the ignition system are new (Cap, Rotor, Plugs, Wires, Module, Coil). What should I do! I worship this pool of knowledge, thanks in advance.

EDIT: Just wanted to add that I read a simiar post, and mod "Ed Maher" noted "just like unplugging it on the old computer controlled carb set-up to do timing, since they didn't typically have the seperate connector the EFI cars have." - I guess that addresses that much... Also sorry if I've violated the sticky if this falls under "Where should I set my timing?".

 

Do not unplug the harness to the distributer. Unplug the single brown wire with a black stripe, the connecter will be breaking out of the harness right by your heater/blower box. Then set timing, if the outer ring has slipped on your balancer like mine your just going to have to go by ear or feel. Try to make another reference point on the balancer and use that to advance/retard a couple degrees at a time.

 

Thanks for the info, I'll give it a go. I've also just read that timing should be set in "Service Mode", this doesn't let the computer advance the timing.