Preferred S54 (and S62) swap fuel pump

[The Dark Side of Will]

It appears that the fuel pump in my '88 325iX just crapped out.

Since I'm prepping for an S62 swap (yes, still... very slowly), I'd like to go ahead and drop an S62 compatible fuel pump into

Since the S54 and S62 use similar fuel pressure, both significantly higher than the standard E30, I thought the S54 group would have some good fuel pump suggestions.

I've also seen this:

E46 m3 fp is cheap and pretty much drops right into the in-tank pump carrier.

A Walbro 255 will do fine, right? Who's the supplier who can get the real ones these days?

[e30polak]

It appears that the fuel pump in my '88 325iX just crapped out.

Since I'm prepping for an S62 swap (yes, still... very slowly), I'd like to go ahead and drop an S62 compatible fuel pump into

Since the S54 and S62 use similar fuel pressure, both significantly higher than the standard E30, I thought the S54 group would have some good fuel pump suggestions.

I've also seen this:



A Walbro 255 will do fine, right? Who's the supplier who can get the real ones these days?

255 will work great, as well as an AEM 320, Aeromotive 340, or DeatschWerks 265

[The Dark Side of Will]

Postponed this...
Car wouldn't start; acted like no fuel. No fuses blown, jumping the relay doesn't help.
Pull rear seat, pull fuel pump access door. Take jumper cables directly from battery and hit (well... with voltage) fuel pump. Fuel pump turns. Plug it back in, car starts. Drive it home and reassemble interior; car still starts.

Da fuq?

It's acting like it occasionally fuel starves, though, so I may need to do a pre-emptive fuel pump. It rolled over 200k on the clock a few weeks ago, on the original fuel pump AFAIK. I have replaced the tank, and all the hoses on top of it, however.

[whodwho]

Next time smack the bottom of the tank, sounds like the pump is failing.

They used to get towed in all the time for a no start and we would carry a plastic hammer and give the tank a whack and drive them in. If the customer seen they would get all pissy that's all it took to get running when they were stuck somewhere.

[The Dark Side of Will]

Yeah, I have heard of that before, now that you mention it.

[The Dark Side of Will]

Car refused to start a few times. it even died in traffic a few times. I smacked the bottom of the tank and always coaxed it to restart.

However, it would stumble a bit, then ramp up to an 1800 RPM idle and be difficult to drive. I finally realized that the air flow meter was crapping out... nothing to do with the fuel pump.

My dad's '87 325iS popped its timing belt a couple of months ago. It volunteered its AFM for me... should arrive Tuesday. That car won't ever need it again, as it'll most likely get a 24V swap in lieu of a rebuilt cylinder head.

[The Dark Side of Will]

I swapped in the AFM, idle motor and DME from my dad's car. My car runs *MUCH* better... I may have a performance chip in my DME.

I *also* realized that the car has an adjustable FPR, but I've never checked the fuel pressure. It would be just like the idiot who owned the car before me to crank the fuel pressure up because that makes it faster, yo. Now I need to build a pressure test rig.

[synergy141]

Have Fuel pump question for the E30 M3 swap guys with the dual fuel pumps and not the single in tank pump on the late model E30's.

My plan is to keep the stock in tank pump and run a Walbro 255 external inline in the factory location under the car.

I've read that that S54 needs 5 bar pressure (70psi) to run correctly and this walbro 255 puts out 60 psi. So I don't know if that'll work or not?

Walbro also makes a 190LPH pump that puts out 85psi.

Which one should I go for?

http://www.summitracing.com/dom/parts/vpn-gsl392bx/overview/

http://www.summitracing.com/dom/parts/vpn-gsl391bx/overview/

[nando]

keep in mind that 60psi is at it's max flow rate. it can put out more pressure, but at a lower flow rate. same with that other pump - it will put out a higher flow rate at a lower regulated pressure.

The in tank pump will help out a little bit since the walbro won't have to work as hard to suck it out of the tank. I think the regular 255 should be fine.

there's also the bosch 044/042, which is better than the walbro but they can be pretty loud and they are fairly large. I don't rember if the 044 is the external version or if it's the 042.

[FredK]

Nando is right. The 255HP will have adequate fuel output even at 5 bar.

https://www.radiumauto.com/Blog/Post/Radium-s-Ultimate-Fuel-Pump-Test-100