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Fass system questions

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Looing into a TST & exhaust soon, but have a couple of questions?

Twin Turbo Questions

I am thinking of buying a fass system but i would like to know how well it performs? From what i have read it doesnt eleminate the factory pump. Has anyone checked fuel pressure before and after? TIA... ... ... ... ... ... ... . Brad
 
I would look at the RASP system it looks like a awesome piece, no electric pump to deal with and no moving parts to break

the fass system is just another electric pump but it is a good one dont get me wrong it will work good too but the RASP in a belt drive pump



Scott
 
On a 12v Brad suggest keeping the OEM lift pump and feeding into it, at least when I talked with him the other week he did. MDW has a pretty extensive write up on installing a FASS on a 12v and I spoke with him just this week about it (if you do a search you will find his post). It is not quite as simple of an installation as it is for the 24v guys, that is if you plan on removing the OEM fuel supply. Fine tuning the fuel pressure and equilibrium with the OEM overflow valve could be a bit time consuming.



After a couple conversations this week I am planning on staying with the OEM lift pump if I do not find any visual air bubbles in my fuel line (installing a temporary clear vinyl hose inline from the OEM fuel filter to the injection pump). Certainly there may be air in the fuel that I cannot see but that is not of a huge concern for me as the visual air is causing a more severe problem IMHO.



For more volume I will use and aux pump that I can turn on and off when necessary (similar to the system from Haisley).



JMHO
 
I'm running a FASS; completely bypassed the stock pump. Drained the stock bowl; cleaned it out; put dry filter in it. It's there if I ever take the FASS out. I have an '03.
 
The FASS eliminates the stock lift pump and fuel filter housing (if you want to remove that too). If I lived in a really cold climate I would probably take the filter out of the stock fuel filter housing and drill and tap the inlet/outlet for AN barb fittings to get full flow through it and also have the fuel heater still in place. I took mine out but I am here in California (No need for a fuel heater).
 
Go RASP no electric pump to deal with i hear there great,

i hear there has been problems with the FASS setup

there have been a few Threads on them in here
 
Fuel Pump

For us 12v guys can a person install a pusher pump back by the fuel tank and tee it into the supply line, i have one that is able to work with diesel fuel and is rated at 7psi, will this hurt anything? :confused:
 
nfox, I personally do not see any need to do this but I do not think that it would hurt either. Some of the higher HP guys are running a aux electric pump that plumbs into the side of the injection pump at the banjo bolt. This is to make up for the lack of volume of the OEM lift pump in extreme HP applications.



For others, BPonci has a 12v and the recommended installation of the FASS on a 12v is very different than that of a 24v. I believe that is why he started this thread.



Brad, have you made any decisions or been able to get any additional information
 
I have had the FASS now for over 15,000 miles. It is setup to completely bypass the OEM lift pump and filter assembly. I check my fuel pressure where it goes into the VP44 and have a pretty constant 13 - 15 PSI. The system is very heavy duty and solid. I have had zero problems with it. The RASP sounds great but I personally would stay with a FASS as I like the simplicity of the electric pump, setup, design and layout. As far as it being an electric vs mechanical I am not worried. The starter is an electric motor as well and we all rely on it. Everything goes bad in time. If I get 100,000 miles out of the FASS I will be extremely happy.



Phil
 
Brad.

When I first put the FASS on my truck I set the fuel pressure at 26 lbs. After a year it was still at 26 lbs. The guy who makes the Preporator called me and told me that they set the Preporator at a higher pressure for 12 valve use. I think it was either 32 or 36 lbs. My pressure stayed constant even at 3/4 throttle for a couple of seconds. I would like to do a better test at full throttle. I had the shop that did the test put the longest line they had on the gauge and hand it to me once I got in the truck. Had to steer and shift with the right hand while I hung out the window and held the gauge with my left hand. Not sure how long the pumps will last holding the higher pressure for our p7100s. Double the pressure, probably less life. Would like to know if there is anything to the air removal claim. Preporator guy says his removes air better than FASS. Preporator also uses a 2000 rpm motor instead of the 3000 rpm motor that is used on the FASS. It might be a good idea to check the amperage on my motor holding 26 lbs versus the amperage draw on one maintaining 15 lbs for a vp44. At least it would show how much harder the motor is working. As they flow 100 times as much fuel as is needed a person might be able to use a slower heavier duty motor, and flow less fuel at the same pressure. Just thinking on the keyboard.

RonA
 
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