I just installed a new walbro fuel pump and eliminated the fuel pump relay and resistor. Im using a maft pro set up and had things tuned pretty well prior to the upgrade. Now with the new fuel pump my afr is below 10 at idle. Is this common when doing this upgrade? Do I have to start reprogramming mt maft pro? Just looking for some insight, thanks.
Walbro fuel upgrade and Maft-Pro
- Thread starter teebone
- Start date
Your pumping in more fuel now then you were with the original fuel pump. do you have an adjustable fuel pressure regulator?
loki2043;1260330 said:
No, the people at horsepowerfreaks said the stock fpr would do the job. I'm wondering if I should just reprogram my maft-pro to take advantage of the fpr not being able to bleed off extra fuel rather than going back to the stock pressure for my 550 injectors.
Yes, you'll have to do some retuning every time you change the setup, especially if it involves fuel delivery.
GrimJack;1260407 said:
Do you think the stock fpr will do the job or is this a necessary upgrade when going with fuel pump upgrade?
you have gone backwards in terms of "normal" upgrades. electronics are usually last after mechanical (fpr, pump, injectors). I dont understand how the tccs is not compensating here unless you have ptt engaged on the maft. The ecu compensated just fine at closed loop when i swapped in the walbro with an afpr compared to a stock pump.
Personally, I think the aftermarket afpr is a must. That said, some have gotten away with their stock unit...teebone;1260421 said:
Assuming you've properly rewired the fuel pump for 12v, I'd say it's absolutely necessary to get an AFPR. You're getting a lot more flow out of the pump. You need to play with fuel pressure to first satisfy the TCCS. Once you hit a good range, THEN tune with electronics.
Pulling that much fuel with a piggyback is never a good idea.
Pulling that much fuel with a piggyback is never a good idea.
shaeff;1260601 said:
This is exactly what I was going to say....pulling a lot of fuel is NEVER a good idea with a piggyback...when we had a piggy back on our truck it ran like crap when having to pull that much fuel with it....got an AFPR and all was good....
After driving the car and reading up on things, I think I am going to get an aftermarket fpr. I there a particular afpr that is better than the others?
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