Well, I hesitate to get in the middle of a fight. But FWIW my brand "A" works good. On the subject of AFPR's in general, most combos don't need them anyway. So, the original poster was making a good point. Don't spend money and needlessly complicate things unless you need to.

Rich

 

I'm with Rich, you don't need a AFPR unless you actually need to chage the FP from stock.

Also, I had a bad Aeromotive regulator back in 2001/2002. I sent it in, they fixed it, and I got it back, free of charge.

I ended up selling it, and putting my stock reg. back on it. I have since replaced the stock one with the 'new style' Aeromotive regulator and have had 0 issues for over a year now.

 

Haven't posted here in a while. Came by to check past threads to see something about Aeromotive quality/problems and lo and behold I probably have my answer to why I have regulator problems.

I just this week received my replacement AFPR from Aeromotive to replace one of the original ones from years ago that was bad. The problem, fuel leakage from the vac. line. It started 500 miles after I put it on my new engine, never really though much of it then. This was back in 2000.

Fast forward to this fall and I finally realize that this is a bigger issue than I thought. I call Aeromotive and they agree to replace the older unit that was prone to failure from reformulated fuel, or so I was told. I got the new AFPR for cost, which I thought was still crappy considering there was a known problem with the original. Anyway, whatever....

So today I go to put the new one on, get everything buttoned up and sure as **** the new one leaks from the vac. line just like the old one did. So now I am a little pissed, to say the least, after spending my afternoon working on the car.

Wish I would've known about the poor quality before going with their replacement. I probably would've steered clear and looked for another brand. Now I'm not so sure I want to go with another replacement....

 

Man am I glad I cam e across this thread. I was reading up on the WS6.com and came across some AFPR dyno numbers http://www.ws6.com/mod-7.htm They claimed they gained over 16.6 rwhp by dropping the pressure to 36psi fromt eh stock 46psi.

I was looking at the Aeromotive units cause they look sturdy. You guys kinda helped me out again. Thanks cause apparently I dont need one, and the one I was gonna get has had issues. A AFPR isnt something I would do my homework on cause as stated its not many moving parts.

 

its not good to drop the press like that.....strains alot of stuff and the whole time the pcm is doing everything it can to correct a lean condition...just leave it stock unless you need more pressure

 

I've had the rail mount LT1 Aeromotive AFPR diapham go bad. I called Aeromotive, but no help. Why can't Aeromotive just sell me the diapham individual part??? I should convert to the non-rail type APFR.

It helps to know problems others have found. Otherwise you have to T_shoot these things yourself. It is better to avoid a problem. I've used many good ideas from this web-site that have worked well for my application. Thanks for all of your help. (97SS D1-383)

 

So you are just creating an excessivley lean condition? As opposed to correcting and overly rich factory set up?

 

i'm pretty sure there was a dispute over those dyno numbers years ago...b/c after a little driving the computer corected it anyway. I don't think the factory is overly rich. Alot of people do.

 

The factory programming "target A/F ratio" in PE mode is typically 11.7:1. You can pick up power by leaning it out. That's how the mail order tuners guarantee a decent (10-15) HP gain on a stock engine.

And you don't create a long term excessively lean condition by reducing the fuel pressure. Almost immediately, the PCM via the O2 sensors sees the A/F ratio in closed loop has leaned out, and starts increasing the long term fuel corrections to add the missing fuel back in. At "WOT" (PE mode), since the PCM is adding fuel via the BLM's in the high load cells, the PCM uses the Cell 15 BLM's to provide the fuel. Hence, you have accomplished nothing be reducing the pressure.... except for a very short period of time.

Why not just "tune" it correctly, rather than diddling around with the fuel pressure and trying to fool the PCM?

 

I am all for it being properly tuned, but I lost you at "Closed Loop", and "BLMs". I do not know the ins and outs of the computer, and how to tune it. I would love a good dyno tune, though I think at this stage of the game I dont think it would help me much.

I have a mail order tune now from MadZ28 now, and I guess it is ok. I know it could be better. I plan on getting Nitrous this year and probably should wait on the tune until after its in.

I can't have two tune stages can it? Where I can flip a switch and the tune changes for Nitrous when I use it at the track, then flip it back when I am driving to work can I? Ehhh Im getting off track and this isnt the right forum. Thanks for the heads up and saving me money on something I dont need, and would have bought and had trouble with.

 

i bought a holly afpr for my setup, somewhere around $170. and then i got the pcmforless tune and they say to keep it at stock pressure. i guess money down the drain.

 

If you already have a mail order tune, you already had to tell him what fuel pressure you are running, as noted in the post immediately above. He sets the injector flow constant based on that pressure. If you change the pressure, you screw up his tune. If it isn't running right, and you feel the source of the problem is his tune, get a good datalog on the car, and send it to him and at the same time tell him what problems you are experiencing. But before you decide his tune is the problem, you better have done your homework to be sure it isn't a specific problem with your engine/setup that is causing the problems.

There's a way to have a "nitrous" timing program in the stock PCM by using the TCS system part of the program. I don't know how to do it though.

You shouldn't need to have 2 tunes. You optimize your tune for running on straight motor, then use external means to alter the timing, and use the jets in the N2O system (assuming its a wet system) to get the A/F ratio correct.

Alternatively, you could run an aftermarket ECU that is equipped to handle multiple programs at the flip of a switch. I use a MoTeC ECU to handle the base tune for the NA stroker, and the second tune required for spraying a dry 300-shot.