wrd1972

Looking for information on the fuel pressure regulator.
Some say it works, others dont.
Who wants to speak to this:
http://www.ws6.com/mod-7.htm

According to this graph it looks like a very produvtive mod.

rskrause

Much safer and more certain to simply tune the car properly by PCM reprogramming.

Rich

Injuneer

OK.... now go back and read the "NOTE:" under the graph, which clearly explains that the PCM compensated for the change in fuel flow through the injectors, and all the power gains shown in the graph disappeared as the PCM adjusted.

It works because stock programming for power enrichment (PE mode) is to rich, and reducing the fuel pressure temporarily leans it out. You can get the same gains, and make them permanent, simply by reprogramming the PE tables in the PCM.

96capricemgr

I will agree with Fred and Rich.
Though I feel compelled to ad that this would cost you more than doing it in the pcm and the pcm work has the oportunity to tweak the timing and in the case of an A4 car the shift points and such as well.

The aftermarket would like you to believe that an adjustable regulator is a good way to tune but then again they sell more crap designed to take your money than make your car fast.
An adjustable regularor can be used by a knowledgable person INCONJUNCION WITH PROGRAMMING to achieve certain goals but for someone with a basic car who doesn't understand exactly everything going on and make the computer work with it they are just a waste of money.

rskrause

Yeah, you're right. We use them all the time on highly modified cars as a gross tuning tool. If it's to rich or too lean everywhere, adjusting the FP is a good way to start to get the whole fuel curve back into the ballpark. For a mildly modded car, it would usually be a waste.

Rich

Injuneer

Mine works fine.... but the only thing I use it for is to run the fuel system at 58psi. Helps the injectors flow more, reduces duty cycle, and helps minimize the upsets to the injector flow rate due to minor variations in pressure.... e.g on a hard launch, when the entire mass of fuel in the supply line is pushing back on the fuel pump. I don't even think I'd play with fuel pressure for a rough cut at a tune.... its still easier to hook up the laptop and make a couple minor changes. But then, I'm not using the stock PCM.

Procharged94Lt1

Yes, they do work as in they adjust fuel pressure, but as many have said its basically a waste on a stock car, you can get more power elsewhere with the $$.

The computer does a fairly decent job in tryin to compensate for changes that you make to it. Until you start throwin major parts at it you should be fine with the stock tune and pressure...

96capricemgr

A stock car can benifit from a pcm tune, a regulator could be used to get fueling right at one point and just screws up the rest unless you go into the computer too. Listen to injuneer prime example of how one can be used in skilled hands and even as a user of one says DON'T TUNE WITH IT.