Guys with Holley TBI - Third Generation F-Body Message Boards

chevyz71man · 09-05-2007, 03:17 PM

Just thought I would share this. Today I went on a hunt for some bigger injectors or something to use in the GM TBI 220 TB. But instead brought home only the fuel pressure regulator. Reason being is you can open up the pressure regulator and take the plunger deal out of it. The removable piece that the spring rests on and the bolt moves. Then insert it into a holley unit. Now you can adjust from 22psi to 41psi in my case with the stock spring. But there is a catch. You need to find the fuel pressure regulator from a newer fullsize van. Like 93-95. Because they ran about 28psi from the factory, and used a different plunger. The other much more common style plunger has the piece that sticks out of the housing so you can see the tension. Works great though, now I just need bigger injectors for the holley.

I also noticed the recommended replacement injector for the 502-6 are the 85pph injectors at 21psi 60pph at 12psi. Which would make sense being they say run 11psi as a factory replacement. These are also the same injectors used in a commander 950 so I am sure they can take some pressure.

327Chevy · 02-20-2009, 08:33 PM

This is exactly what I am looking for. A way to increase the pressure on my holley 670 TBI.

Has anyone else tried this? It seems like such a good piece of information, I wonder why there were no responses since 2007?