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Suburban_Tyler · 10-23-2013, 01:43 AM

I was doing some reading about fuel pumps and pressures and come across this on another forum. Thought I'd share if it's not already here somewhere.

Here is a little fuel pump tech…..

Just a little background. I’m installing a 2004 5.3 in a 9 GMC Sierra. When the fuel pump question came up I read that you needed to use a Delco EP241. To double check this I called S&P and they said also to use a EP241. Just for giggles ( after I installed the EP241 in the tank and truck ), I checked the specs on these pumps. Now what I got were specs from Airtex book where I work at Carquest.

EP241 ( E3210 Airtex) = Flow= 40 gph & PSI = 65-75
Now that pressure reading is right on the head of the pump at the lab and if you take into account filters and lines and lengths, it’ll probably equate to 50-55 psi… should be.

I wasn’t to impressed with those # and did some checking. I went up in years and found the EP381 pump used in the early vortec trucks, cyclones, ect….and here are it’s #’s

EP381 (E3270 Airtex) = Flow = 50-60 GPH & PSI = 80-90
Here again that psi rating is under perfect conditions at the lab and on the head of the pump. It should yield you a 70-80psi in the vehicle.

I called Airtex and talked to their guy Craig there. He confirmed these numbers I have here and inquired what I was working on. I told him and he said.. quote “ you should never use a EP241 on a vortec or LS1 motor” Craig went on to explain that it would work but the pump would be working itself to death to maintain the pressure and that would shorten the lifespan dramatically. He also explained that the EP381’s were manufactured with a new thin magnet design which yielded a lot higher torque that the EP241’s. They were specifically designed to work on Vortec & LS1 style engines. Also he said the current draw on the EP380 would be significantly less than the EP241, less current = less heat=longer life.
The EP241 is designed to work with TPI & MPI and should only be used in this application

I had my pump out fixing a split hose anyway so I went ahead and got the EP381, well our Airtex E3270.

Just wanted to pass along this little tid-bit of information. I know you guys with newer trucks already have high flow high pressure pumps in the tanks from the factory. But maybe this will help others with their modifications.

10-23-2013, 01:43 AM	#77
Suburban_Tyler Registered User Join Date: Aug 2011 Location: Jefferson City, Missouri Posts: 62	Re: Help with fuel system design for LS1 install I was doing some reading about fuel pumps and pressures and come across this on another forum. Thought I'd share if it's not already here somewhere. Here is a little fuel pump tech….. Just a little background. I’m installing a 2004 5.3 in a 9 GMC Sierra. When the fuel pump question came up I read that you needed to use a Delco EP241. To double check this I called S&P and they said also to use a EP241. Just for giggles ( after I installed the EP241 in the tank and truck ), I checked the specs on these pumps. Now what I got were specs from Airtex book where I work at Carquest. EP241 ( E3210 Airtex) = Flow= 40 gph & PSI = 65-75 Now that pressure reading is right on the head of the pump at the lab and if you take into account filters and lines and lengths, it’ll probably equate to 50-55 psi… should be. I wasn’t to impressed with those # and did some checking. I went up in years and found the EP381 pump used in the early vortec trucks, cyclones, ect….and here are it’s #’s EP381 (E3270 Airtex) = Flow = 50-60 GPH & PSI = 80-90 Here again that psi rating is under perfect conditions at the lab and on the head of the pump. It should yield you a 70-80psi in the vehicle. I called Airtex and talked to their guy Craig there. He confirmed these numbers I have here and inquired what I was working on. I told him and he said.. quote “ you should never use a EP241 on a vortec or LS1 motor” Craig went on to explain that it would work but the pump would be working itself to death to maintain the pressure and that would shorten the lifespan dramatically. He also explained that the EP381’s were manufactured with a new thin magnet design which yielded a lot higher torque that the EP241’s. They were specifically designed to work on Vortec & LS1 style engines. Also he said the current draw on the EP380 would be significantly less than the EP241, less current = less heat=longer life. The EP241 is designed to work with TPI & MPI and should only be used in this application I had my pump out fixing a split hose anyway so I went ahead and got the EP381, well our Airtex E3270. Just wanted to pass along this little tid-bit of information. I know you guys with newer trucks already have high flow high pressure pumps in the tanks from the factory. But maybe this will help others with their modifications.