I just put a new 350 TPI in my 91 firebird to replace the 305. I am running open manifolds right now just till I get my -pipe, but I cant get the timing set, the car just backfires and spits and is very hesitant. I had a timing gun on it and as soon as you get close to zero it dies. Then I looked at the light and noticed that it will stop blinking for a split second, but it only does this on cylinders 1 and 2. And yes I have new coil, cap, rotor, plugs, wires etc.

anyone have an idea?
could it be a knock sensor?

 

are you sure you have the correct rotor position?
and firing order

 

Small cap distributor?

 

If you don't already know, the correct firing order is 18436572... Make sure the #1 cylinder is at top dead center (easiest way to find TDC is to pull the #1 spark pug out, with the coil wire disconnected, place your finger over the spark plug hole and have someone else bump the starter until you hear the pfshhh forcing your finger off the spark plug hole. Stop and that is TDC.) then set the rotor to point directly at the #1 cylinder. The post on the cap that is in line with the rotor will be the starting point as the #1 spark plug wire. Stock timing should be at 6* advanced with the spark advance wire disconnected (usually found on the pass side of the engine compartment by the heater box). Hope this helps.

 

I tried all those things already like 10 times. Nothing seems to work

 

Have u checked your fuel pressure, also make sure u have no vacuum leaks. That will cause additional frustration with gettin the timing set. Is this your first time firing it or no.. Check your plugs and make sure you have fouled them or anything.. Ur right there tho.

 

Is it a small cap or not?

 

It sounds like your harmonic balancer might have slipped and is no longer really indicating tdc. I had that problem once. I could get the car to idle but as soon as I tried rotating the distributor to get to tdc, it would die. my reomendation is to find tdc like badazta87 said and get it to idle. then take the timing light and see if the knotch on the harmonic balance is anywhere close to 0. if it isnt, then you need to replace the balancer.

 

isnt base timing on a tpi suppose to be aorund 6 degrees??

 

when i put headers on my car i put a new jegs ignition module in it. I could never get the timing set right, it had to be advanced alot to start cold.
finally one day i was doing a burnout and the car just died. Put the original delco module back in, started, ran great and could set the timing correctly.

 

Did you reuse the 305 balancer on your new 350?

Often this "dying when I get the timing set low enough" is a mismatch between the old balancer and the new timing tab. The usual "gotcha" is when you reuse an original 12:00 position balancer (like many 305s used) in combination with a 1:30 position timing tab (commonly supplied with aftermarket and universal replacement engines). The mismatch is about 30* between the two. By the time you get the timing mark down onto the tab you're already about 20* retarded from what it indicates- the engine dies.

Not sure if this is the problem for sure, but it's a common "gotcha" when swapping in an aftermarket or univeral replacement 305 in place of many factory 305s.