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FASS, RASP or AirDog?

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Cranks

hp/tq estimate

What fuel system is the best or most recommended? I have been looking at the RASP, FASS and AirDog? Also, which is the best for the money? I would also prefer it not to be too loud. I have a 2005 Ram which will have twins,etc. 500-600hp. I also know that these may not be ready for the 05, but let's consider they are available to work with the in-tank pump. Thanks.
 
I would have told you Airdog a month ago based on my research but they almost doubled their price after the company was sold. Way to expensive now. The RASP I have heard good things about and it is all mechanical, more expensive than FASS but less than the Airdog. I'm not sure what HP rating it will support up to though.



It's easy to find info on all 3, all 3 have had good reviews. The FASS has had a few more gripes than any of the other's but I think that's probably because there are more FASS out there than the other 2. Look them all up on your own, people's opinions are great but you can make a good decision based on your needs with all the info you will be able to find.
 
Rasp

I have a set of Twins and a set of Don M's Mach 5's and have no problem with the RASP. The more rpm's the more fuel. . plus you sill have a back up L/P in case of a problem. . It is a lot of money, But don't get cheap on getting fuel to your motor. At WOT it will stay at 16 lbs of pressure. I added all the big fuel lines too. Try looking at www.powerbypoole.com.
 
I like the FASS.

Not just because I bought it, but its cheapest! Good warranty, has all the parts you'll need to install it.

Only takes about 3 hours or less to install.

Everything is a breeze to install, just tedious and time consuming.
 
You are asking abot two totally different products. First decide if you want a mechanical system (rasp) or an electrical system. If you choose electrical know this. FASS filters are readily available, NAPA sells 2 micron for $30. 00 always in stock. Air Dog uses custom one of a kind filters, so hope they don't go out of bussiness. FASS hangs down below the truck further but not much difference in my opinion otherwise. AD will tell you you can't fill a FASS equipped truck without shutting down but that is old news and has been repaired. The FASS people have been making upgrades based on what they are seeing from the field, so the product continues to get better. A lot of the little things that caused us early FASS owners trouble have been resolved. Rasp has a lot of good points. I have not seen one installed yet and my imagination may be the cause for me not wanting one. I like my fuel lines tucked in against the frame and am not sure I want another pulley hanging off the front of my truck. With that said it seems to be a bulletproof setup. Maybe the best for overall reliability. I'll put my upgraded FASS up there as I feel very comfortable with it now.
 
I was a little leary of the RASP also but mine just survived 2400 miles on the Alcan hwy. Beat the truck to death and the RASP performed flawlessly on my 3rd gen. I've got pictures in my readers rigs gallery.



Richard
 
Wow that doe look nice. Better than I expected. Wonder how the fuel lines will hold up over time. I am pretty sure there is no push lok hose rated for suction. Hose on the supply side of the pump would be the only hose in question. Not flaming RASP here, FASS uses the sam thing on the supply side to thier pump. I have seen problems on Diesel generators using push loks on the supply side. Usually on old hose or stuff with crazy bends in it. Hose can suck closed. I have SS braided n my supply just to be safe.
 
I have tested the push lock hose and fittings up to 1,500psi. At 1,750psi it let go pushed the same hoses and fittings back together they would only hold 350psi.
 
I have tested the push lock hose and fittings up to 1,500psi. At 1,750psi it let go pushed the same hoses and fittings back together they would only hold 350psi



I'd like to know if anyone has installed a RASP on a 12 valver or if it would support the higher demand fuel pressures they need??..... Andy
 
With the right spring in the bypass fitting I don't think pressure will be any problem at all. During some trouble shooting I pinched off the return from the RASP and SLOWLY increased rpm. At 1300 rpm I was already at 37 psi. Pressure and flow are no problem at all. If you could see how slow this little pump turns for a given output you'd be amazed. I know that there are people running it closer to a 1 to 1 drive ratio but the ratio that it comes with is more than enough for my needs.



Richard
 
I am very comfortable with the pushlok fittings and do not doubt them. The problem is with the hose and not under pressure. Pressure ratings tell you zero about the hoses capabilities to remain open under suction. The supply side of the pump is under vacuum and sees no pressure. As far as I know none of the hose used with push lok fittings is rated for use as a suction hose. It usually works well unless kinked or I have also seen older hose seperate and suck closed.
 
I've been wondering about this subject for a while also. I'm planning on installing the Comp that should be here in about 3 days and some twins and injectors somewhere after that as soon as my warranty is up and I have a new clutch. I'm pretty much sold on the FASS for now at least so here's the big question for those like me who haven't really done their homework.

What does the FASS for my application cost???

-R. J.
 
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