.....stopped engine right away-parked it. Fixed fuel leak. Changed and flushed oil twice. What brand lifters and or cam if I decide to replace are reccomended?? Has 150k miles on orig. engine. I should rebuild or do a crate, but finances are limited. Going to tear down top end too inspect cam, see how bad if any damage- runs fine-just makes a single lifter noise.

What about putting in the "hotter" 1985 305 tpi cam from GM??

This is my first post. Hi to all.

Hi and welcome...I'm pretty new here too and don't really feel qualified to be the welcoming committee.;)
If your engine is an 86, like your sig, the TPI cam will work. At some point around 84-85, I don't recall what year, GM changed the block from the traditional flat tappet cam and lifter to factory roller lifters. The cams are different between these 2 engines and won't interchange. The 88 305 -350 TPI cam is a little better than the 85 cam also. Are you familiar with the lifter adjustment procedure?? They are adjustable and with that many miles should really be adjusted. Hopefully that will get rid of the tick and keep the engine running for a while longer.:)

Hi, thanks for the welcome. Yes, 86 5.0, same as sig. Mine has the hyraulic flat tappet. I am going to inspect and adjust valve lifters this weekend. From listening to noise with a stethescope, I can here the tick noise coimg from what sounds like middle area near #6 ex. lifter.

I have read about that change too. I think somebody wrote it was in 86 or 87, I know have the typical hydraulic flat tappet lifters though.

I have researched the adjustment procedure and have done it before.
I will try the adjustment first and let you know. I hope that makes the nosie go away.

OK, I couldn't ermember when the change was. You would have to stay with the 85 cam then or get an aftermarket one. You have an endless choice in cams !!

Good luck with the adjustment..:thumbsup: