My original ICM went bad after 318,000 miles and from this pic it looks like it's time to change the whole distributor. What kind do you guys recommend for a small cap HEI replacement? The car is a 1992 TA 305 TPI daily driver.




1992 Trans Am Distributor at 318,000 miles

 

IMO, just a stock replacement (new or rebuilt) is all you need.

 

If you have a good ICM & pick-up coil in a (new and non-worn-out) distributor, you should be good.

 

Since there's nothing inside that distributor except the magnetic pickup to collapse the field and a module, a stock replacement from your local auto parts store will work just fine.

Personally, I'd stick with a GM module. Aftermarket modules tend to fail too much and an OEM module can take a lot of abuse.

 

I don 't mean to Hijack, but I will for a quick reply...I degreased my '86 305 and discovered the cut on the base of my distributor. Is there a factory explanation for this, or a PO mucking about? Engine was pulled from the car with ~55,000 miles on it, with an intact wiring harness.

 

I dont know, but you have a nice timing mark now

 

The simple answer is that whoever did the intake manifold gasket (notice the not factory looking black RTV) put that notch there as a marker to put the distributor back in the exact same spot it came out of .

It's still prudent to check the timing though , as those marks make sure the distributor body made it back to the same position it was in before , but are no proof whatsoever that the distributor's driven gear is on the exact same teeth of the camshaft's drive gear as it was before removal .