Fuel System Upgrade questions

[TJBrown]

I am inthe process of building a 420a (machine work is being done now) and am wondering if i could go ahead and do the fuel system upgrade per vfaq.com. I was going to do a rewire, install a WALBRO 255, and install an AeroMotiveFPR. I read that it will cause the car to run rich but my question is how rich? I hope to have the built engine in the car (a 2.2 n/t) by January do to the lead times on parts and the turbo hung on it by March. Any info would great.

 

[OSXer]

Where did you read that it will run rich if you install an appropriate FPR?

Generally people run into issues when they install a 255 pump, but expect the stock regulator to work properly. In that instance it will be overran and run you rich. People still manage to run their car, but it's poor on gas milelage and worse off on power. However, since you've got the FPR listed as an upgrade as well, what is the worry?

 

[DSM97GST]

buy a afc2 or dsmlink and your worries are gone

 

[TJBrown]

I can get DSMLink now? I was under the impression that you had to have a Turbo for it to work properly. I will not have the Turbo installed until March. Maybe a little sooner.

 

[Woodsy0]

As of now, to the best of my knowledge, DSMLink isn't compatable with non-turbo ECUs. Even if you turbocharge your N/A, DSMLink won't work with your existing ECU. Good news is there's other tuning software out there.

As for the fuel system, there are more than several DSMTuners members that report running a re-wired 255 without an AFPR, although the general consensus is that anything over a re-wired 190 should be accomodated with one. The main issue with having an over-run FPR is a potentially stumbly and otherwise crappy idle, since your new fuel set-up will be pushing more fuel through the rail with the same volume being spit out by the injectors. The excess fuel over-runs the stock FPR.

If adjusted correctly, you shouldn't run rich at all, since a properly adjusted AFPR would route the excess fuel back to the tank.