This engine was in a '89 IROC I bought a couple years ago. PO said it was rebuilt and from a '86 TA. Its .030 over, dbl-roller timing chain, Racer Brown Cam ground locally here in Md by 4Secondsflat.com. Its the EH4.
http://www.4secondsflat.com/RB%20Cam%20Specs.htm
It has good compression and ran well the 2-3 hours run time I have on it. I pulled it partially apart for paint and to verify the PO statements. You can see from the pics below its .030 over and the identifying ID marks on the rod caps.
I was ready to install it when I came across a Vortec 350 I couldn't refuse.
I also have the almost new 19lb injectors I bought for it too for sale.
https://www.thirdgen.org/forums/engi...injectors.html
I put it back together...new head gaskets, valve cover, front timing cover & seal, oil pan.

 

Engine is sold but injectors still for sale