I recently installed an 620-12454 130GPH fuel pump from CPperformance on my 94 454. Since there were no marking as to inlet and outlet I assumed it was the same as the factory big block mechanical pump (in the front and out the rear) After trying for quit some time I still can not get fuel up to the carb. I have lossened the line at the "inlet" and I have fuel there but nothing at the inlet to the carb. Has anyone installed this pump? Am I correct to assume the in and out are the same? How long does it take for a 130GPH pum to push fuel 2 feet up to the carb. I dont want to burn up a starter stying to get it there.

After installing my fuel pump, I had to prime the engine before it got fuel to the carb. Almost killed a fresh battery trying. Then put a little gas donw the carb throat and firted it up. Took two times priming before it got the carb full & it would run on it's own.

Thanks, I tried that and would only sputter as long as I poured gas in carb. I finally got someone at GM who sells what looks to be identical. He gave me a test to try and and in and out are 180 out from the factory one. guess is off to buy and bend more fuel lines and see if that works.

so you have a gen 4 block and the pump is installed on the block or is it a gen 5 block with the pump on the water pump.?

Update... all be it rather late. Come to find out after some further testing and a phone call that the inlet and outlet are reversed from the factory pump. After re bending both lines it works great.