I recently changed my exhaust system from what I thought was a 2 1/4 (was 2 inches)exhaust with turbo mufflers. Then new mufflers exhaust is 2 1/4 with Delta Flow 40 series mufflers. Car runs good and appears to be breathing a whole lot better. It pulls strong thru first and second gear but when I shift into third it falls flat on its face like it has cut off. If I let off the gas and them get back on it it will pick up speed. I currently have a Holley mechanical 110gph fuel pump on it. I noticed the other day that at idel the fuel gause only showed 3-4psi. Does it sound like I may have a fuel issue ? Before I changed the exhaust I didn't have this problem.

its not the exuast and 4 pounds aint enough fuel pressure so start there .did you crush your fuel line or kink it when you changed the pipes

My car did the same thing when it was too lean (jetting). It would stall, then come back as soon as I backed off. Check the things above 1st. 3-4 psi may be ok at idle. I think you need around 5-7 reving up.

Sounds like fuel pump to me. I used to run the Holly pumps in my goat but they just wouldn't hold up to the Houston heat. Switched to the BG HR 220's and solved my problem. I case you are wondering why I used two pumps, one is a back up. Been stranded to many times.

Had the same problem once, wasnt exhaust or fuel pump. It was a bad gas cap that caused a vacuum in the tank. And to GTO68TX I have a lot of friends that have had fuel pump problems. I run a Mallory pump and its about 18 years old now. Never been a problem.

THanks guys.