F.a.s.s. Fuel System

[bobo]

hey any one ever try or use a F.A.S.S. fuel system on an E9? or an E7? Im thinking of getting 1 for the superliner but not sure what one to get. bobo

[peterj]

I had one I put on a 3406 cat. Didn't make any more HP. It did make easyer start. It is just a fuel strainer, then a high cap elec pump, then another fuel filter, with another return line to the tank. It also has a fuel heater built in.

I had trouble with the electric motor/pump freezing up. I don't think there worth it for the cat. The mack fuel system is a lot like the bosch on a mack. Increasing the transfer fuel pressure does NOT make more HP.

The filters cost more too.

If you had a old leaky fuel system it would hepl, but why not just fix your fuel sysstem, ie new hoses and fix suction leaks. Ihave one in the shed I took off... locked up motor!!! Put a new filter head and new lines on the truck , it ran just as well as it did with the FASS....

Thats just my opinion...YMMV..lol

[Underdog]

More snake oil, I say. I ran a Fuel Preparator(same principle as FASS, they stole the technology) on my E-TECH 427 for three years with no advantage in horsepower or fuel economy. When I replaced fuel lines and converted to single draw/single return, I removed the unit and put it on the shelf where it sits. If anybody would like to try it, I will send it along with exta filters for the cost of shipping.

[bubbamobilin]

hey any one ever try or use a F.A.S.S. fuel system on an E9? or an E7? Im thinking of getting 1 for the superliner but not sure what one to get. bobo

I ran a fuel preporator on an 1989 Superliner with and mechanical E7 400, it made all the difference in the world. The truck never ran well when it was below 1/2 tank of fuel and the primary filter was always half empty when I would change it. It definitly helped with the power and fuel economy. It helped with the power so much I was able to go from a 4:42 ratio to a 4:17 ratio with a T2090 transmission and the engine was able to pull it without modifications. When the fuel preporator went bad I replaced it with a FASS system and we are still running it to this day. I also built a 1990 Superliner with an E9 500 and before I ever put it on the road I installed one on it too. I am still running the E9 500 also. I will never be without one of these systems as long as I'm running trucks with mechanical injection pumps and mechanical supply pumps. I talked to an engineer at the Hagerstown Powertrain Plant and he told me that as long as the electric pump could maintain 1 pound of pressure at the supply pump it was a benefit.

[bobo]

I ran a fuel preporator on an 1989 Superliner with and mechanical E7 400, it made all the difference in the world. The truck never ran well when it was below 1/2 tank of fuel and the primary filter was always half empty when I would change it. It definitly helped with the power and fuel economy. It helped with the power so much I was able to go from a 4:42 ratio to a 4:17 ratio with a T2090 transmission and the engine was able to pull it without modifications. When the fuel preporator went bad I replaced it with a FASS system and we are still running it to this day. I also built a 1990 Superliner with an E9 500 and before I ever put it on the road I installed one on it too. I am still running the E9 500 also. I will never be without one of these systems as long as I'm running trucks with mechanical injection pumps and mechanical supply pumps. I talked to an engineer at the Hagerstown Powertrain Plant and he told me that as long as the electric pump could maintain 1 pound of pressure at the supply pump it was a benefit.

Im thinking the same as you. On a mechanical pump, and inj's., which is crude system how could it not help, by pushing the fuel a bit and refining it. On an electric pump/high psi inj. I dont think it would help. Thats why Im asking. A few years ago when I was shop foreman we installed taggers(fuel atomizers)they didnt do a thing on the c15's but old mech E7 400 gained almost a half gallon.

Bubbamobilin what f.a.s.s part number do you use? thanks bobo

[ThaddeusW]

These type of units are popular with diesel pickup guys looking to turn the fuel way up. Supposedly they can keep a thirsty, modified injection pump well fed when the foot goes to the floor. If you are not turning up your engine or using serious fuel system mods then I would not bother.

[theakerstwo]

These type of units are popular with diesel pickup guys looking to turn the fuel way up. Supposedly they can keep a thirsty modified injection pumps well fed when the foot goes to the floor. If you arent turning up your engine using serious fuel system mods then I would not bother.

I will agree with that. On a stock engine thare had to be a problem with the system to gain any power with the Fass.

[bubbamobilin]

Im thinking the same as you. On a mechanical pump, and inj's., which is crude system how could it not help, by pushing the fuel a bit and refining it. On an electric pump/high psi inj. I dont think it would help. Thats why Im asking. A few years ago when I was shop foreman we installed taggers(fuel atomizers)they didnt do a thing on the c15's but old mech E7 400 gained almost a half gallon.

Bubbamobilin what f.a.s.s part number do you use? thanks bobo

Bobo,

I'm not sure which f.a.s.s unit I'm running but I will check it out and get back to you. My E7 is running the f.a.s.s system and my E9 has a Fuel Preporator. I think I would take up Underdog's offer to pay shipping on his unit and try it. He was trying to run it on a E-Tech engine and these engines have a better supply system and I don't think the benfit is as great.

[Underdog]

The offer still stands. My unit is about 7 years old it has been sitting on my shelf wrapped up in the original box for 3 years. It was working when I took it off. Be glad to give it up to anybody thinks they can use it.

[bubbamobilin]

The offer still stands. My unit is about 7 years old it has been sitting on my shelf wrapped up in the original box for 3 years. It was working when I took it off. Be glad to give it up to anybody thinks they can use it.

My friend Dan has a 94 CL with an E9 and he might want to give that thing a try. I'll talk to him and see.

[bobo]

More snake oil, I say. I ran a Fuel Preparator(same principle as FASS, they stole the technology) on my E-TECH 427 for three years with no advantage in horsepower or fuel economy. When I replaced fuel lines and converted to single draw/single return, I removed the unit and put it on the shelf where it sits. If anybody would like to try it, I will send it along with exta filters for the cost of shipping.

Hey Underdog I will take you up on the offer! (thanks bubbamobilin) do you ever come up to ontario? hamilton area? if not how do I get the money to you? got paypal? bobo