[cadtech]

I have a 1980 Turbo Trans Am with the 4.9L engine. I teed a pressure gauge in to the wastegate hose and took it for a test drive. I can only get 5 psi of boost and the third boost light will not come on. The correct carburetor has been rebuilt and the PEVR is working properly. I checked the secondaries to make sure they are opening up completely. Everything seems to be working as intended. What am I missing to get to that 6 plus psi of boost?

[quizkid32]

Try here...probably better for specific turbo information.
https://ttaperformance.com/

[78w72]

Originally Posted by cadtech

I have a 1980 Turbo Trans Am with the 4.9L engine. I teed a pressure gauge in to the wastegate hose and took it for a test drive. I can only get 5 psi of boost and the third boost light will not come on. The correct carburetor has been rebuilt and the PEVR is working properly. I checked the secondaries to make sure they are opening up completely. Everything seems to be working as intended. What am I missing to get to that 6 plus psi of boost?

these engines were designed for 9psi, most were never at that amount & part of the reason they got a bad rep... a properly running 301T has just about as much HP as a 78-79 400 W72, which isnt much by todays standards.

many of these cars had an adjustable waste gate actuator valve, it will have a threaded rod that you can adjust to increase the boost to 9psi or a couple pounds more, if it doesnt have that threaded rod you can gently bend the mounting bracket to increase the boost a few psi. beyond that you need an adjustable boost regulator you can buy or make one yourself.

not too many 301T guys on this forum, check out 301garage.com for all the 301T info you will ever need. joe from TTA performance is on there too but there is so much more good info related to these cars from the forum owner & other members.