PEVR Rebuild


Active Member
Feb 22, 2003
The Power Enrichment Vacuum Regulator (PEVR) is an important component for the pre computer '78'-'80 draw through turbo cars. They aren't reproduced and so far nobody has come up with a good alternative. I had one in pretty bad shape and recently had it rebuilt by a company called TTA Performance Inc. in Kenosha, Wisconsin (**not to be confused with the Buick vendor TA Performance in Arizona**). TTA Performance specializes in the '79-'81 Trans Am with the draw through turbo 301 engine. That engine also uses a PEVR that looks a lot like the Buick version except has a shorter stalk. The diaphram inside these valves dry rot over time and become unusable. But TTA Performance can open them up and replace the diaphram making them like new. The cost was $75.00 to have them rebuild mine. I am not in any way affiliated with them or benefit from posting this company's information. There are few companies out there still offering draw through turbo parts and services, so I thought I would pass this information along. They also have an interesting YouTube channel (TTA Performance) that shows them testing modified turbos, throttle body fuel injection, E85 fuel, a fabricated intake manifold, etc. Everything they are doing to enhance the performance of the 301 would have similar results for the 231 draw through turbo cars. Below is a picture of an original PEVR on the left and the one they modified and repaired for me on the right.


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