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Filter before Lp

Can’t find my Walbro pics. This one is from PMDCable.com. IIRC, the way things worked out, the filter looks like it is downstream of the pump but, trust me, it isn’t. A 180 off the pump is required to feed the IP
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Member Buddy posted his set up back in 2009. Not sure what pump he was running.
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If you get too tall of a filter, you’ll have to adjust things to get the set up inside the frame rail.
 
As WW pointed out, the FRC-10 is/was supposed to be for a DS-4 but, the point is moot as Walbro doesn’t list them on their site anymore.
FRB-5 (45 gps at 8-11 psi) is supposed to be for non-electronic injection pumps though the one I bought through a site vendor was offered with the OEM LP to OPS plug and worked fine for my DS-4 pump. I forget who got it from me.
Specs on the various Walbro Pumps can be had chasing this link to the FR series pumps page.
Or, https://www.walbro.com/fr-series-fuel-pumps/ if the inserted link doesn’t work.
I checked a few of them and didn’t luck into one better than the FRB-5. Your searching may discover one that is.
 
@Paveltolz does it keep up with the fuel demand under load? I'm curious since every LP I have tried always gave me good pressure at idle but as soon as I went under load like accelerating up a freeway on ramp pressure would drop to almost nothing till I was up to speed!.
 
@Paveltolz does it keep up with the fuel demand under load? I'm curious since every LP I have tried always gave me good pressure at idle but as soon as I went under load like accelerating up a freeway on ramp pressure would drop to almost nothing till I was up to speed!.
Add up the cost of all the ones bought and compare it along with ip lifespan loss and mechanical repair time to determine when one of the big boy LP becomes worth it.
 
@Paveltolz does it keep up with the fuel demand under load? I'm curious since every LP I have tried always gave me good pressure at idle but as soon as I went under load like accelerating up a freeway on ramp pressure would drop to almost nothing till I was up to speed!.
Sorry Amigo, If I wasn't gifted the AirDog, I'd still be running the Walbro but, passed it on to someone else back in 2013 and can only say I don't remember it dropping off more than a few pounds at WOT. If it had, I think I would have remembered...being pretty unhappy about it. Plus, I wouldn't have passed on a POS to anyone.

Currently, BigT runs the FRC-10 on his 94 and I think he had one on his 99 too. I understand they may drop to around 4psi but, I'll let him chime in on actual experiences. Whether choosing the Fass, AirDog, Raptor, Carter, Walbro or something else, They're all an improvement over OEM. Truthfully, it comes down to the $$$ you're willing to spend against the manufacturer's reputation. For a while there, Walbro had a great rep and then it fell off. Leroy was selling the FRC-10s for a while but now he's marketing kits for the Carter, Fass LP (not the filtered versions), AirDog Raptor and AirDog DF-100 if that tells you anything.
 
Not saying walboro is a pos, it is equal to or better than the AC Delco EP158. The pressure matches the 158, but lasts longer. Adding the higher cost and modification required it is questionable to me to be worth it. While 4 psi isn’t as bad as going into vacuum, it is shortening ip life.
I stayed with the ep158 because i had a db2 in my trucks and hummer that doesn’t want over 8psi. I made a deal with the napa guy and bought them from him bringing my old one each time. They lasted about a year and he hassled his delco rep and would get me Delco discount credit because of it. If you can get it to maintain that pressure and it oives for 4 years- maybe worth it.
To me - $300 vs $425- (maybe dating myself by price) the extra $125- $200 is worth the longer ip life and no more worries. Then the better flowing LP can live pushing through finer filters.
2c
 
As WW pointed out, the FRC-10 is/was supposed to be for a DS-4 but, the point is moot as Walbro doesn’t list them on their site anymore.

I called Walbro and asked why I couldn't get these anymore. They retooled their factory during the slowdown from the lockdowns and they simply haven't made another production run of these.

One other difference of note is the higher pressure pump would pump on a timer regardless if it needed to move the plunger or not. So it was a steady ticking from the FRC. The lifetime in hours on their site is less than the FRB and this is likely why.

The FRB will pump when needed. So you open the water drain and you hear the pump click faster.

These plunger pumps are "Flow on fail" so fuel can still flow if they quit. Some the high end pumps mentioned above are "Instant engine shutdown" and call the hook to drag it home. When the brushes failed in a lift pump I was using, well, just another coast to a stop on the side of the road through 6 lanes of traffic...

Of the large pile of dead lift pumps in my graveyard the FRB-5 outlasted them all and even the pickup. Marginal for pressure just like most of the others though.
 
I called Walbro and asked why I couldn't get these anymore. They retooled their factory during the slowdown from the lockdowns and they simply haven't made another production run of these.

One other difference of note is the higher pressure pump would pump on a timer regardless if it needed to move the plunger or not. So it was a steady ticking from the FRC. The lifetime in hours on their site is less than the FRB and this is likely why.

The FRB will pump when needed. So you open the water drain and you hear the pump click faster.

These plunger pumps are "Flow on fail" so fuel can still flow if they quit. Some the high end pumps mentioned above are "Instant engine shutdown" and call the hook to drag it home. When the brushes failed in a lift pump I was using, well, just another coast to a stop on the side of the road through 6 lanes of traffic...

Of the large pile of dead lift pumps in my graveyard the FRB-5 outlasted them all and even the pickup. Marginal for pressure just like most of the others though.
Are there any good - pumps that will last a long time and make proper pressure - that are flow through on fail?
 
Are there any good - pumps that will last a long time and make proper pressure - that are flow through on fail?

The AirDog DFs are flow on fail. I’ve read that it isn’t but those comments were directed at the Raptor which is AirDog but, as already noted, a different pump set up, Mine certainly is, unfortunately but, thankfully.
I’ve read that the FASS pumps initially were not but, they were redesigned and supposedly do now.
Raptors, as noted by commenters on other forums, apparently aren’t.
Kennedy lists a $225 pump that apparently flows unpowered. Don’t know what the GPH or PSI is. He’s closed the first week or so of June.
Can’t speak for the Carter.
 
If you find a pump that is not flow on fail, there is a fix. Add a T fitting before and after the pump. Connect the two T together with a one way check valve in the middle. The check valve is to allow the ip to draw fuel around the LP when it is off(dead). But will stop the LP from pumping a loop. Basically -point the arrow towards the ip not the tank.
Low cost ones can be had for $5, About $30 puts you into a descent stainless steel unit. Hmmwvs/ Hummer uses one that is ridiculously marked up price of over $200 as their solution to keep fuel from draining back to the tank after shut off when the LP dies to ensure start up. Gee I wonder why so many hummers have ip life way under 100,000 miles- SMH. With no hard start symptoms, no pressure gauge to tell the driver, and an already slow rig that just runs a little slower accelerating and on the hiway- 99% of drivers never know a difference.
 
As I read the discussion about what is the current acceptable LP, and a question of what looks like wanting more flow, an older E-mail conversation with Stanadyn regarding the IP is coming back to my mental recall. IIRC, the DS4 does not want a lot of pressure and have something like 12 psi max on the mind. From Will's inputs, it looks like the DB2 is 8 psi. So while not directly helping with the LP question, it is a data point. Yes, I know that there are observations of pushing more than those numbers to the IP, so don't flame me for passing along the manufacturer's comments ;)

What I am hoping is driving the original question of a filter upstream the LP is that the in-tank filter (aka: sock) was removed. If not, might consider making this part of the project.

Regarding observations of pressure drop while accelerating / WOT. Once I got the fuel system straightened out (sock removal, healthy IP, healthy LP, new injectors, feed the beast mod), do not recall more than a couple psi drop while WOT. If the pressure started to drop more than a few psi under load, I had problems in the system (like the one time when somebody dumped a lot of fine crap in my fuel tank).
 
Hi all I’m back on my optimizer install after a long hiatus due to home remodeling. Just in time for the 100 degree temps here in St Louis.IMG_0246.jpegIMG_0247.jpeg Looking to source a lift pump. Was going to go with direct fit one from Quadstar but it isn’t listed on the site anymore. Did anyone find out the psi on the LP from Kennedy? I was planning on installing a filter before the LP, delete the sock and use the stock FFM. Any suggestions would be greatly appreciated. Oh I guess you can’t get transmission lines for these trucks anymore either. Have trouble sourcing these to. Thanks.
 
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