I have a '85 TPI Iroc that I bought last fall with a bad motor. After researching and planning my build for months I just finished pulling and replacing motor. I wanted to keep this a TPI and fairly OE looking. Here is a partial list of what I used.
New GM 350/L31 4 bolt shortblock
Melling M55 oil pump
Melling pickup 55-S1
Melling oil pump shaft IS-55E
Patriot Performance 60cc assembled heads
Comp roller Cam 08-501-8
Comp Magnum rocker arms 1417-16
Comp timing chain and gear set 3136
GM Lifter kit 12371042
Trick Flow fuel injectors 24 lb. 89024
Edelbrock intake 3860
Hooker Super Comp headers
Magnaflow Exhasust
OE LTR & plenum
This weekend I finally finished it up. After priming it and getting the distributor installed properly it fired right up.
I had my son in the car with instructions to check oil pressure and keeping the RPMs around 2000 while I was checking for leaks and messing with timing.
We had good oil pressure (around 60 psi) but wan't so fortunate with the leaks
I noticed a lot of Anti freeze running on the floor so we shut it down.
Ended up being the heater hoses by the firewall were leaking badly.

Next time we ran it I was again watching for more leaks and trying to set the timing but was having trouble finding the mark, finally figuring out it was advaced way to far.
About the same time I started to notice a lot of smoke coming from the back driver side of the engine.
Had my son shut it down again. But this time I think we got it up to about normal operating temperature before shutting it off.
I say think, because the temperature gauge appears to be not working, but I don't think it got to hot.
We only had it running around 5 minutes; 10 max. but after I got the timing close, it was running good.
It looks like (and I am hoping) that all of the oil was coming from the valve cover since I did not use silicone on both sides. (I wanted to keep easy access to the rockers)
After resealing them and adding a little oil I started it back up today to get the final timing teaked and check again for leaks.
Thats where it gets ugly and discouraging.
It didn't instantly fire and when it did it ran sort of rough, wanting to stall, and worst of all, there is a hell of a squeeling sound coming from the motor. Sounds like dry bearings or a belt slipping. We turned it off right away. First thing that came to mind was the bearings in the water pump or alternator. Unhooked the belts, and the water pump, alternator, A/C all spin freely with no noise or resistance.
Now I am really worried that the noise is in the engine itself.
What do you guys think, and what can I check.
I know I didn't run it to low on oil and I had good oil pressure and I am almost positive it didn't get to hot when I ran it the time before.
This is my first real build and got all my build info right here from lots of reading and pouring through threads.
I have a ton of hours in this, not to mention a few dollars and don't want to see it end badly.
Thanks, Tim