Hello Everyone: I was just wondering if anyone knows the stock tpi fuel pump's volume rating. Vortech provides a 155lph booster (in line) with its kits and it seems to me that a stock in-tank unit would have to be able to flow at least that much or theoretically, the booster pump could draw the line dry and kill both pumps. Does this sound correct, or am I missing something?? Any input would be greatly appreciated. Thanks.

 

The stock replacement pump that NAPA sells is rated at 16gph or 60.57lph. You'll need more than that.

A Walboro 255lph in-tank unit may work instead of using an inline booster pump. But I would use both.

 

I actually just replaced my stock unit with that very pump!! I also am in the process of adding its 255lph in-line cousin as a booster. It turns out that, in my case, it may not be entirely necessary, but it's going to happen anyway. The really weird thing is that according to Vortech's old (circa 1993-95) sales literature, they advocate using a T-Rex (50gph@70psi) with the stock in-tank or 155lph in-tank fuel pumps (for the Mustang 5.0). But, if you look at the graphs on Racetronix.com or APEUSA.com, it appears that such a large discrepancy between flow rates would cause problems with both pumps. The system appears to be "top heavy" in these scenarios: the downstream pump pushing way more than the in-tank one can deliver even at 0-10psi. There's obviously something I'm missing here, I just can't pin it down. Anyway, thank you for your input.

 

You would be amazed by the number of people running FMU's who decided that instead of following the instructions, and installing the vortech or Procharger in-line pump, they would run a 255 lph in tank and call it good.

Then they would complain as thier fuel pressure fell off at full boost, or wouldn't even get that high to begin with on our dyno. I have seen this on both ford and GM's running the FMU. we have even jacked up cars and installed the pump, on the dyno, at great cost to the customer, just to shut them up about "BUT ITS A 255LPH!!! AND THE IN LINE IS ONLY 155 LPH!!!" So that they could see what we were talking about.

FMU = the extra power of the additional in-line to help keep pressure up in the range you need.

no FMU = do whatever you want.

 

My fuel pump is apparently dead (5psi output and a lot of noise). This is understandable considering I haven't yet installed my booster pump that came with my procharger. A booster pump seems like such a kludge though, and I was about to order a BBK-1630 225lph in tank pump assuming (incorrectly according to posts above) that it would be adequate without the booster. Can anyone explain why that wouldn't work using an explanation other than "I showed someone one time why on this one car it didn't work?" The reason I ask is the spec sheet for the pump says 225lph and 100psi which seems like enough but I would love to understand the physics that keeps this from working.

 

because it doesn't do what they say it will. the "boosted" version of it doesn't either.

Like I said above, get rid of the FMU and run wide band, then that pump will work fine, otherwise, quit trying to outsmart the ATI company unless you want to be posting in a thread about dead engines and blown head gaskets and get that in line pump installed.

 

geese , so I can expect fuel problems with my boosted Wlabro 255lph pump on my T-62 turbo ? I was gonna run an FMU

 

yes, unless you run a large diameter in line pump with the FMU. The solution is that under the heavy loads the geometrically larger in line pumps have the torque to deal with the heavy loads created as the FMU closes and raises the fuel pressure to the incredible levels all the while supplying a volume which is acceptable. No tiny in line pump, regardless of how much its "rated" for will do that. Otherwise they would just include 255lph in tank pumps in the FMU power adder kits.

 

the stock pump is very weak,i use the walbro 340 and i use a hot wire to by-pass the factory power lead cause in upper RPM the voltage gets reduced check this site out www.racetronix.com

 

I have the booster pump that came with the Procharger, so I guess I'll use that, it just seemed a little kludgey. Should in that case (since I already have to replace my fuel pump) I just get a stock replacement pump, or is there a compelling reason to have a high(er) volume in-tank pump with my booster pump?

 

I'd get the 255 anyways, it's hard to over fuel an engine in most cases. Besides that if you lose the FMU and go to bigger injectors and a tune you'll be in decent shape.

The reason a booster works well isn't the raw flow, it's the pressure; if you're running an 10:1 FMU with 8 PSI boost, you're talking some major pressure; even a 255 Walbro is 255lph at the rated 43 PSI base fuel pressure; The booster pump allows each pump to see a lower pressure differential and therefore opperate more efficiently.

 

Yeah, I suppose whats really a kludge is the FMU. I already have an AutoProm so larger injectors with my new high flow fuel pump would probably be the best solution to this problem.

I'm probably getting into a subject to be covered in another thread, but is there any way to get the fuel pump out without cutting off the exhaust and dropping the tank?

 

Walbro 340 and a hotwire kit is almost always enough for 10's....

HTH!

 

It all depends on what your HP goals are. The Walbro was good up to about 7-8 psi for me, before the fuel pressure started dropping (no FMU, just an Aeromotive regulator with base pressure at 52, and 55 lb injectors). I was able to add pulsewidth to make up for the lack of pressure, and keep the wideband readings steady, but I still should upgrade to a dual in-tank or a big external...