hi guys are the chev turbo 400 a bolt in to replace the ponty 400
cheers  

The only difference between the TH400 used in a Chevy and the one used int he Pontiac was the Pontiac trans had a notch cut out of the top of the bellhousing. The bolt patterns are exactly the same. The Chevy TH400 should bolt right in.  

thanks phil
i can look for a chev just to get it going again cheers  

Don't waste your time looking for a Chevy trans, it won't bolt up. The bottom bolts are spaced the same width as the middle  bolts on the Chevy (look from the front of the trans, the bottom bolts sre directly below the middle bolts), on a Pontiac the bottom bolts are spread wider apart than the middle bolts by about a half or 3/4 inch. Buick, Olds and Caddy also used the same pattern as Pontiac, so look there first.
Steve