E46_M3

I'm currently contemplating the necessary fuel pump upgrade (along with pressure reg, 650/740's, etc on an EJ25/ '93 JDM WRX) and wondered which route others had taken.

Though the Walbro seems a popular choice I wondered what others had done, and I'm specially interested in anyone with info on having used Bosch.

Is there any sound reasoning for having an external/internal (to tank) pump. It seems that Bosch are quite often mounted externally by other car manufacturers. Is it just whatever the designers happened to opt for? I realise that certain pumps have a greater capability to 'pull' fuel rather than 'push' etc.

ZEN Performance

If you don't want over 450hp, stick with the walbro. Otherwise look at a larger intank pump, like the bosch (there are others too), if you need good fuel surge resistance for track use, then consider an external pump with swirl pot.

E46_M3

thanks for your input Zen

Bob Rawle

You could always do this, I used the 044 Bosch pump as I have gone thro' three Walbro's in the last two years. No problems down to 1/8 tank so far.

bob

Dark Blue Mark

Looks quite tough Bob!

harvey

iTrader: (48)

The Walbro is ok for medium power to the level Paul suggests. Say 450 bhp or in that area +/-.
Above that I favour the 044 Bosche and my preference for both is in tank.
On both Bosche and Walbro installations, by adjusting the angle of the pressed bracket and the pick up sack I can on occassion add over 60 litres of fuel so the system is picking up to the last couple of litre.
On a new installation I am about to copy Bob's idea so that under heavy acceleration when the fuel runs to the rear, even on low fuel load, there is still pick up.
I also have a "fuel tank sump kit" on order and wait with interest to see what it is, maybe just a few plates to weld into the bottom of the tank.
Incidentally, I have found O/E ver 6 STi fuel rails operate OK well over 500 bhp.