fuel pumps: Bosch VS walbro

[hachirusto]

Hey guys

Just want to get some opinions about what would be a good external pump to replace my second hand VL pump

just want to gauge opinion on the Bosch 044 vs the walbro equivalent

I was leaning towards the 044 but then heard that in the last year or two the quality of them have dropped off and stuff up pretty quickly.

motor is just a NA 4age with usual mods so not chasing max fuel delivery more reliability

[Delazy]

if its just a N/A motor then u certainly shouldnt need either of those pumps...massive overkill...

[hachirusto]

so you think just get another VL pump? will have to price them up at work today , 044 is $199 from just jap

[H8CHIR6KU]

get a genuine bosch vl pump. they are a little pricey. not as much as that 044. and they should come with a 1year warranty. just ask when you buy it if it comes with its warranty.

when i was working 6 months ago, all bosch electrical items came with a 1 year warranty.

and usually if it doesnt go in the first few months she'll be right

[ke70dave]

standard ae86 jdm jo fuel pump is around 80Litres/hour at about 3bar. standard 4age fuel pressure is around 30-40psi at idle.

from this:



a bosch 044 is 200litrs/hour @ 5bar.

more than twice the size of the standard pump flow, and just under twice the the pressure

now assume toyota used a safety factor in their pump selection, of more than 3 (probably but unconfirmed). the 044 is a MASSSIVE over kill.

now some will say "nothing wrong with a huge fuel pump, keeps things safe", partially correct. if you have a fuel pressure regulator that can handle that huge flow and press (which i dont think the 4age one can), and given most people dont upgrade their fuel lines, you are asking a huge pump to pump through some tiny lines, which could lead to premature pump failure.

not to mention that you are just pumping your fuel around and around and around your HOT engine bay, as well as the heat that the MASSIVE fuel pump would be giving to you fuel. hot fuel isnt all that great for engines, as it easily boils and turns to vapour, causing such dramas as vapour lock.

also a bosch o44 is an EXTREMELY loud pump especially after its been on for a long time, heating up the fuel. it will drive you insane.

i ran a 044 on my 4age temporarilly (borrowed from a mate after a failed pump). the noise drove me up the wall!!!

my recomendation? a bosch911 pump , 95Litres/hour @ 4 bar or walbro equivilent. can be had for around $200 brand new in the bosch. probably cheaper if walbro make one this small.

i have this on my stocko 4age with a surge tank setup. i also have a fuel pressure guage and have confirmed that the standard 4age fuel pressure regulator is able to withstand this pressure and flow and produce the correct fuel pressure.

[Skylar]

Do they not teach you about pumps in some fluid dynamics unit? Pumping through tiny lines will just make the pump sit on a different point on the operating curve. Should just flow less as there's more head to fight against. Will be fine, however, running a pump at either end of the operating curve will cause premature failure.

Number 2: Stock pump moves less fuel than big pump. Big pump will circulate more fuel quicker through the rail and reg and back to the tank whereas little pump moves less fuel slower. Big pump will give fuel less time sit in the rail and absorb heat whereas little pump will give the fuel more time to absorb heat. The little pump will be better in that a lesser percentage of fuel is returned to the tank but the difference will be minor.

[claw]

unless you have changed to 12mm fuel feed lines dont bother even thinking about an 044 it wont work as soon as you open your throttle

bosch 070 is a external vl/bmw pump, cheap as chips and work forever, plus warranty is great

i ran a 070 on a standard ae71/ke70 tank and never had fuel surges just be sure not to really thrash your car when your gotting down below a quarter

[H8CHIR6KU]

external vl pumps also run 12mm inlets with an 8mm outlet.

[claw]

I know this but 044 tries to pump so much fuel that if you run standard metal lines under your car, unless only slightly opening your throttle, your car will not be able to rev at all

[hachirusto]

ok thanks guys

I was going to pick up a goss stock replacement VL one from work for about $110 but will price up the 070 and see how much they are going for