Is there a chance that any 1970 Z-28's came with a 10 bolt rearend?

No. 1970 was the last year for the 12 bolt.

If it is a 71+ Z28 it will have an 8.5" 10 bolt.

Thanks i had someone telling me some 70 z's had 10 bolts put in them after the GM strike however i didn't think the strike was until 71-72?

Just to be sure, I asked this question over at NastyZ28 for you:

http://www.nastyz28.com/ubb/Forum24/HTML/001637.html

Thanks very much, im pretty sure they did not have a 10 bolt but wanted other opinions. 350/360HP LT-1's needed the 12 bolt.

It looks like the guys over there agree that the 10 bolt was never put behind a 70 Z28. Are you looking at buying one or something?

Yes buying one this weekend, all correct with the exception of the rearend.

Cool!

If you haven't joined over at NastyZ28.com yet, please take the time to do so, and head to the original drivetrain topic so that the members there can tell you all you need to know about originality. They won't steer you wrong.

-Bill

the 300HP 350 with a 4spd had a 12 bolt. A Z shouldn't but they were doing anything to get the new model out.