Quick Question

[Pal]

do i need to re dyno tune the safc after putting in my new walbro fuel pump

cheers for any help

Eric

[fr0st]

You won't need a tune. You fuel pressure reg keeps the pressure constant at the injectors so increasing the fuel pressure/flow before it won't affect it.

[Pal]

thanks frost

[mitchy_]

does that mean we can spam now?

[Pal]

go for it ,i got what i needed

[RRob]

A retune wouldn't hurt. Could of been running out of fuel top end before and tuned to suit the dying pump...

[Steve]

Theoretically, the FPR will keep the pressure constant, in reality it does usually result in a slight increase in rail pressure and you car will be running a little rich

For the few $$$ it costs to get a car on a dyno, and check your AF ratios, it isnt a bad thing, alternately, put a fuel pressure guage on there, and see what its reading - should be 2.55kg at idle, 3.05kg at atmosphere. Most decent workshops will have a fuel pressure guage, will take maybe 15 mintues to check the pressure, if that.

[Pal]

thanks steve, i may just hold on to it and get some money for a dyno then put it in.

[chrissso]

Hey,

I replaced my fuel pump because my fuel pressure was dropping from 50psi to 40 on 10psi of boost and high revs.

I wouldn't have changed my fuel pump if I had enough pressure, so I can only think that you've changed your's for the same reason, or you were bored and/or wanted to change you fuel pump.

Because I changed my fuel pump to a Walbro, I now had 50 at full revs, on the current tune, and the afr's went rich, so I needed a retune.

So, If you change your fuel pump due to a dropping pressure at high revs, then chances are yes, you will need a retune.

[Duncan]

Definately put it on a dyno. When I installed a walbro it ran fine at load and medium revs, but ran out of flow at hight revs making it dangerously lean.