so here's my story:
i bought my 1990 IROC about 2 weeks ago, but getting it started every time gives me trouble. When i talked to the previous owner about it, he said he had advanced the timing belt for maximum performance. Now my question for the people of this forum is; how do I go about changing it back to factory default setting? That's all I really want.

 

if it is an iroc with a 305 tpi then it doesnt have a timing belt. it has a timing chain. you would have to pull the front cover and bring it up on top dead center and see if the dots on the cam and crank gear line up.

 

thats what i meant....thanks

 

I don't think the PO actually advanced the timing by repositioning the timing gears by removing them. Use the timing procedure in the TGO Tech articles.