Adjustable fuel pressure regulator

[Coelacanth]

Anybody have one they're not using? I like the look of the black Accufab BREG model but I'll consider anything that's working and comparable. Thanks.

 

[TurboTom72]

Hi. I have an Accufab unit that's going to be put up for sale soon. Just waiting on new parts to arrive before I list it. $100 plus shipping.

 

[Coelacanth]

Thanks Tom, and a few who PM'd me. I bought a billet Kirban's unit from one of you. Much appreciated!

 

[Dennis Kirban]

If you got a Kirban one you own one of the best.....sold over 25,000 of the ones for the 5.0 Mustangs..in the Mustang world it is known as the billet one or Kirban one...they just don;t realize it comes from a Buick company as we sell to the major Mustang suppliers.......all made in the USA by one individual since 1990......we also get 4 versions made for the Porsche market as well....

denniskirban@yahoo.com

 

[Coelacanth]

Thanks Dennis, good to know I'll be running one of the best. So regarding fuel pressure readings, you're supposed to "disconnect the vacuum line" and look for 37 - 43 PSI. Which line do you disconnect, the one coming from the top of the pressure regulator adjacent to the front end of the fuel rail? Mine's still stock at the moment. I saw with key on, pressure was over 25, and dropped to just over 20 when idling, with the vacuum line connected.

I want to get some baseline data before installing the fuel pump, hotwire kit and do Earl's suggestion for a battery-to-frame ground wire.

 

[Coelacanth]

Well, it's a good thing I installed a gauge on the rail because it's showing me my fuel pump is slowly dying. I'm only getting about 37 or 38 PSI with the vacuum line off. I already have a Walbro pump & hotwire kit, that'll be going in the car hopefully before the weather gets too cold. I also received that Kirban billet adjustable fuel pressure regulator. It needs a polish but more importantly, the orange O-ring it came with has a few nicks in the outer edge. Does anybody have one or two of those they could send me? I went to Gregg Distributors here and they had nothing that would match (a bit too large I.D. and too thin).

 

[Joel.e]

37-38 is normal for the stock regulator

 

[Coelacanth]

According to my instructions for the AXiS interface & chip, fuel pressure needs to be 43 PSI with vacuum line off...so that ultimately needs to be my goal. I should be able to get there with the new fuel pump, hotwire kit and adjustable pressure regulator. But back on topic, this Kirban regulator shipped to me in working condition but the orange O-ring attached to one of the I/O tubes probably needs to be replaced and I would like to know where I could find one. I'll upload a pic later tonight.

 

[1KWIKSIX]

Why not contact Dennis Kirban?
I'm sure he can source one of those "O" rings for you

 

[bison]

Viton o rings will work. You can pick up an assortment for about $10 at most auto parts stored. I only use 2 or 3 sizes in the entire box before I have to buy a new box but it's silly way more convenient to replace the box when I run out. If you don't work on these cars often an assortment will last you forever


Sent from my iPhone using Tapatalk

 

[Coelacanth]

Why not contact Dennis Kirban?
I'm sure he can source one of those "O" rings for you

I did, he said it's not an item they stock. Which seems strange because the O-ring looks like it's specific to the regulator. Here are some "before" pics, this unit needs a polish job pretty badly. The diaphragm inside looks good, no cuts or tears. I think the pics capture the little nicks in the outer edge of the orange O-ring.

 

[DR BOOST]

isn't it the same as a fuel injector o-ring?

 

[Coelacanth]

After 600-grit and 1000-grit wet-sanding (ran out of 800...dammit!)...tomorrow I'll rub it out with rubbing compound, that'll hopefully take care of the swirlies.

 

[Coelacanth]

isn't it the same as a fuel injector o-ring?

I've never had my injectors out, so I don't know.

 

[Coelacanth]

Here's a before/after shot of the restored FP regulator...turned out really sweet.

 

[Coelacanth]

I'd like to install this bad boy this evening, but I have a couple questions. My baseline fuel pressure readings seem low, maybe 37 - 38 PSI with vacuum line off; with what I believe is the original fuel pump and OEM regulator. I'll be upgrading the pump & adding a hotwire kit in the next week or two, I realize the original pump is probably not cutting the mustard anymore. I'm not installing the adjustable regulator to over-compensate, I just want to install it because it's an important upgrade, going forward.

My question is, will installing this Kirban regulator and adjusting the pressure back up to the 43 PSI that's recommended by my AXiS chip & interface do anything bad to my original pump? Will the weak pump actually prevent me from adjusting pressure up to 43 PSI?

 

[Coelacanth]

Well, I went ahead and swapped out the OEM FP regulator for the Kirban adjustable one. Turned the key, no leaks. Started the car, no leaks. Let it idle for a few minutes and I was easily able to adjust it up to 43 PSI; with the original regulator, it never exceeded about 38 PSI. My AXiS interface & chip instructions say to adjust FP to 43 PSI, which is why the original unit never getting even close to that was concerning me.

I went out for about a 10-minute test drive, it seemed to pull harder...I did a little brakestand, and I launched just after boost barely started to register with the lights on the dash--maybe 4 pounds?--and discovered that I'll be needing to upgrade something else--my rear tires! I previously needed to build up boost to at least 8 or 9 pounds before the tires would start to spin. I realize the original dash boost indicator lights are far from accurate but the fact that my tires started to spin after boost barely began lighting up seems to indicate I'm really making progress with this car...and 235's on the back just aren't gonna cut it anymore.

Looks like drag radials--255's at least--will be added to the "must have" list for next season.

 

[Pronto]

Add a real boost guage to that list. The stock boost "guage" is as useless as tits on a nun.

 

[Coelacanth]

That's true, of course...and I have plans to add a 3-bar MAP sensor and feed a line to a UTCOMP-PRO device...winter project.