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What's the scoop on the various AFPR's?

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Old 03-02-2024, 02:14 PM
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What's the scoop on the various AFPR's?

Been researching these on here but a lot of the posts are more than a decade old. Saw a lot of slamming the Holley ones but that's 2007. Is there a preferred one? I have a piece of junk from way back and I can't get it below 50psi with a racetronix pump. There's also BBK which doesn't seem like a favourite either. The screw is a royal PIA to access, I get that, but it's a once and done operation so the extra expense on the ease of the Holley doesn't make a lot of sense to me.
Old 03-02-2024, 04:29 PM
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Re: What's the scoop on the various AFPR's?

Not an expert on them, but I recommend using the AFPR from Southbay. Yes, the screw is a bit of a pain to adjust. But like you said, once it's set you don't have to mess with it. At a minimum, if you buy from them you'll get great customer service.
Old 03-02-2024, 04:34 PM
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Re: What's the scoop on the various AFPR's?

Originally Posted by blacksunshine'91
Not an expert on them, but I recommend using the AFPR from Southbay. Yes, the screw is a bit of a pain to adjust. But like you said, once it's set you don't have to mess with it. At a minimum, if you buy from them you'll get great customer service.
I saw that one. But it's a Philips screw. How can you possibly access that when the plenum is on?
Old 03-02-2024, 04:56 PM
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Re: What's the scoop on the various AFPR's?

Never mind. It's a 8mm, not a Philips. Not sure where I got the notion it was a screw head. Definitely would like the South Bay one but the shipping to Canada is ridiculous as are most things to this place.

Last edited by EDGE; 03-02-2024 at 05:29 PM.
Old 03-02-2024, 08:33 PM
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Re: What's the scoop on the various AFPR's?

I run the Holley and really like it, it is a more compact design that does not have the nut on the top for adjustment but a flat dial that you can adjust with your hands, no tools required. It is more money than others but seems really well built.

Here it is:

512-501 Stock Replacement Adjustable Fuel Pressure Regulator - JEGS

Old 03-02-2024, 09:21 PM
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Re: What's the scoop on the various AFPR's?

I have 350 TPI in my 87 Monte Carlo SS. I used the Holley AFPR about 5 years ago. The problem I had was the diaphragm failed after a few days, dumping fuel into the vacuum line. That was a common problem with those units back them. I hope that Holley has improved over the years. I currently used the AFPR from SouthBay.

Fred
Old 03-02-2024, 09:33 PM
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Re: What's the scoop on the various AFPR's?

Originally Posted by Fred SS
I have 350 TPI in my 87 Monte Carlo SS. I used the Holley AFPR about 5 years ago. The problem I had was the diaphragm failed after a few days, dumping fuel into the vacuum line. That was a common problem with those units back them. I hope that Holley has improved over the years. I currently used the AFPR from SouthBay.

Fred
I’ve had mine on for at least 5-6 years with no issue but that really is lousy to have one fail so quickly.
Old 03-03-2024, 07:47 AM
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Re: What's the scoop on the various AFPR's?

I've been running an Aeromotive (#13301) for over 10 years without issue. Fuel pressure is always stable and I never had to readjust it. It makes funky noise on initial priming but that's about it. That was right from day one, so I don't hear it anymore.

Never mind, I see you have the OEM set-up. Aeromotive won't fit there.

Last edited by SbFormula; 03-03-2024 at 07:54 AM.
Old 03-03-2024, 08:57 AM
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Re: What's the scoop on the various AFPR's?

Originally Posted by SbFormula
I've been running an Aeromotive (#13301) for over 10 years without issue. Fuel pressure is always stable and I never had to readjust it. It makes funky noise on initial priming but that's about it. That was right from day one, so I don't hear it anymore.

Never mind, I see you have the OEM set-up. Aeromotive won't fit there.
Geez, how do you even plumb that thing in? Must be quite a few adapters involved.
Old 03-03-2024, 09:17 AM
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Re: What's the scoop on the various AFPR's?

I was thinking that 5 years was a relatively short life, and thought I had better experience, maybe more like 20 years or better. However, my memory has limitations, so I use other means to "remember" things for me. Looking back in archives that were created on Windows 98SE machines, I found the information I sought.

Back in February of 2000 I installed the AFPR on my '86. That's 24 years, or in automotive terms, roughly the useful lifetime of three Tesla batteries. It was a Rochester unit, converted to adjustable pressure for about $1.00 (2000 cost). It still works without leaking. Holley may likely be "in business" long after I am not, but mine works.


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Old 03-04-2024, 07:16 AM
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Re: What's the scoop on the various AFPR's?

Originally Posted by EDGE
Geez, how do you even plumb that thing in? Must be quite a few adapters involved.


That was for the FIRST TPI Intake. It won't work for OEM.






Old 03-05-2024, 10:16 AM
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Re: What's the scoop on the various AFPR's?

So reason I was asking about AFPRs was I think I have an issue with mine. After @SbFormula laboriously and quite graciously and effectively helped me tune my car, I discovered a fuel pressure anomaly once I installed an AEM digital gauge. It's running at 43 psi vacuum connected. When I unplug it it goes to 50psi. With the screw fully out it won't go below 50psi. Then when I crack the throttle or hold it for a couple seconds at a higher RPM, the fuel pressure drops to around 37 psi. So I'm wondering now if there's an issue with that diaphragm.
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Old 03-05-2024, 01:51 PM
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Re: What's the scoop on the various AFPR's?

I wonder if the disc


that comes with the regulator is to thick, or if the regulator housing is to short. In the pics I've enclosed, one is with the disc one without. With it the regulator sits pretty proud. That's with the screw removed as well. The disc is 1/8" thick.
Old 03-05-2024, 06:00 PM
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Re: What's the scoop on the various AFPR's?

Originally Posted by EDGE
but the shipping to Canada is ridiculous as are most things to this place.
www.crossborderpickups.ca


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