Increase Fuel Pump Pressure

LeafPile · 12-16-2017, 11:33 AM

My 1993 YJ has a 20 gallon tank factory (with the "mod" of course). It doesn't fit well in between the frame rail, and I don't need that much fuel. So, I'm getting a 15 gallon tank meant for the 87-90 YJs.

Since these Jeeps run on either 4-5 psi (4.2L carb) or 15 psi (2.5L TBI), it's not even close to my 31-40 psi. My pump puts out 40 psi and is vacuum regulated down to 31 psi. I have three options (let me know if you have a fourth):
1. Find a pump (probably aftermarket) that fits into the new bolt pattern on the tank.
2. Put in a new regulator on the rail that ramps 15 psi up to 31 psi at full vacuum and 40 psi at zero vacuum.
3. Put in a regulator somewhere on the system (probably near the filter on the framerail) that ramps 15 psi up to 40 psi, and keep the factory regulator.

First off, I don't really like the idea of upping the pump pressure. I'm not sure this is even safely possible...

12-16-2017, 11:33 AM	#1
LeafPile Join Date: Nov 2017 Posts: 5	Increase Fuel Pump Pressure My 1993 YJ has a 20 gallon tank factory (with the "mod" of course). It doesn't fit well in between the frame rail, and I don't need that much fuel. So, I'm getting a 15 gallon tank meant for the 87-90 YJs. Since these Jeeps run on either 4-5 psi (4.2L carb) or 15 psi (2.5L TBI), it's not even close to my 31-40 psi. My pump puts out 40 psi and is vacuum regulated down to 31 psi. I have three options (let me know if you have a fourth): 1. Find a pump (probably aftermarket) that fits into the new bolt pattern on the tank. 2. Put in a new regulator on the rail that ramps 15 psi up to 31 psi at full vacuum and 40 psi at zero vacuum. 3. Put in a regulator somewhere on the system (probably near the filter on the framerail) that ramps 15 psi up to 40 psi, and keep the factory regulator. First off, I don't really like the idea of upping the pump pressure. I'm not sure this is even safely possible...