anyone modded the factory fuel pressure regualtor
anyone modded the factory fuel pressure regualtor
I heard somebody talking about just modifying the factory FPR by just drilling and tapping the top for a machine screw and jam nut, then placing a quarter as a spacer inside or something.
is this too off the wall or has anyone else heard of this? I"m only running a mild setup so it's not crazy. I ordered a gauge today and from what I see in the stock setup and an aftermarket there dosen't seem to be much there that's worth $60 in the FPR's
is this too off the wall or has anyone else heard of this? I"m only running a mild setup so it's not crazy. I ordered a gauge today and from what I see in the stock setup and an aftermarket there dosen't seem to be much there that's worth $60 in the FPR's
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Joined: Feb 2000
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From: Schererville , IN
Car: 91 GTA, 91 Formula, 89 TTA
Engine: all 225+ RWHP
Transmission: all OD
Axle/Gears: Always the good ones
lol
I would mod a stocker before I bought another aftermarket one.
Its just as u described, do a search and u should get tons of responses that way.
Been beat to death.
If u do it and yours has any miles I would recommend getting a new diapragm, just so u dont go thru it and then have it let go on you :-)
later
Jeremy
I would mod a stocker before I bought another aftermarket one.
Its just as u described, do a search and u should get tons of responses that way.
Been beat to death.
If u do it and yours has any miles I would recommend getting a new diapragm, just so u dont go thru it and then have it let go on you :-)
later
Jeremy
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Joined: Feb 2000
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From: Schererville , IN
Car: 91 GTA, 91 Formula, 89 TTA
Engine: all 225+ RWHP
Transmission: all OD
Axle/Gears: Always the good ones
go to a Carquest store.
Or go to the part stores and look thru the catalogs.
I know for a fact u can just get a diaphragm I have before.
later
Jeremy
Or go to the part stores and look thru the catalogs.
I know for a fact u can just get a diaphragm I have before.
later
Jeremy
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Yep, thats what I did. Ordered a new diaphragm from the local parts store (Standard Ignition part, they sell both with and without the metal piece) and drilled a hole, smashed the recessed top to gain clearance for the quarter, had a nut welded to it for free, threw a bolt in there, painted it... instant adjustable FPR.
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Supreme Member
Joined: Jul 1999
Posts: 2,149
Likes: 4
From: Mims, Florida
Car: '87 IROCZ
Engine: 395 ZZ4
Transmission: ProBuilt 700R4
Axle/Gears: 9 bolt 3.70s
I believe that there may be a tech article on this matter on this home page, take a look.
But really, why mess with the stock FPR. You have to get a nut welded to the top of it and a new diaphram is a good idea. If you bought a Holley AFPR, the job would take a couple hours max and you be done.
But really, why mess with the stock FPR. You have to get a nut welded to the top of it and a new diaphram is a good idea. If you bought a Holley AFPR, the job would take a couple hours max and you be done.
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Joined: Feb 2000
Posts: 7,015
Likes: 2
From: Schererville , IN
Car: 91 GTA, 91 Formula, 89 TTA
Engine: all 225+ RWHP
Transmission: all OD
Axle/Gears: Always the good ones
Cause a qrtr and 10 minutes of work saves you about $50.
Damned regulators are $50-60 for a crappy lid with a nut on it and new plenum gaskets lol
I never would have bought one if I knew that then.
later
Jeremy
Damned regulators are $50-60 for a crappy lid with a nut on it and new plenum gaskets lol
I never would have bought one if I knew that then.
later
Jeremy
I may be able to save you from searching. Here's what I did to make mine fully adjustable:
TPI AFPR Conversion.pdf
TPI AFPR Conversion.pdf
Moderator
Joined: Feb 2000
Posts: 7,015
Likes: 2
From: Schererville , IN
Car: 91 GTA, 91 Formula, 89 TTA
Engine: all 225+ RWHP
Transmission: all OD
Axle/Gears: Always the good ones
That Vader,
Always a showoff cause he can type and import pictures and stuff :-)
lol
U realize that was for TBI not TPI right?
later
Jeremy
Always a showoff cause he can type and import pictures and stuff :-)
lol
U realize that was for TBI not TPI right?
later
Jeremy
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Joined: Jul 1999
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From: Atlanta, GA, US of A
Car: 94 Z28
Engine: LT1 w/ headers, catback, CAI, tune
Transmission: 4L60E
Axle/Gears: 3.23s
If you don't want to go to the trouble of fixing a nut to the top and making it truly adjustable, you could just get a gauge and experiment with putting a shim in the top of the stock FPR until you reach about the desired FPR. I ran a quarter in mine, supposedly added about 4-5 psi over stock, I never got around to verifying it though.
Supreme Member
Joined: Jul 1999
Posts: 2,149
Likes: 4
From: Mims, Florida
Car: '87 IROCZ
Engine: 395 ZZ4
Transmission: ProBuilt 700R4
Axle/Gears: 9 bolt 3.70s
You can not go out and do this job in 10 minutes, thats total BS.
Just to get the nut welded onto the top of the stock FPR is going to take how long???? Now if you are a welder, then maybe after you got the FPR off, then just maybe 10 minutes later you got the nut welded.
And I think that you have to weld the nut on for a good reliable AFPR. So this is a most, and a person like me who doesnt do his own welding, this part of the project is going to take an hour at least.
I still stand by what I said above, when its all said and done, I think its more effective to buy a good AFPR & install it.
Just to get the nut welded onto the top of the stock FPR is going to take how long???? Now if you are a welder, then maybe after you got the FPR off, then just maybe 10 minutes later you got the nut welded.
And I think that you have to weld the nut on for a good reliable AFPR. So this is a most, and a person like me who doesnt do his own welding, this part of the project is going to take an hour at least.
I still stand by what I said above, when its all said and done, I think its more effective to buy a good AFPR & install it.
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Joined: Aug 2001
Posts: 1,337
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From: Wesley Chapel, Florida
Car: 1991 Camaro Z28
Engine: Dart SHP 406ci T88 turbo
Transmission: T56
Axle/Gears: QP 35 spline Ford 9" 3.50 gears
I did. It came out pretty neat also. I tack welded the nut in place and filled it in with JB Weld to stop vacuum leaks. No problems. Check it out...
Last edited by pwdbychevy; Feb 23, 2006 at 08:36 PM.
Supreme Member
Joined: Jul 1999
Posts: 2,149
Likes: 4
From: Mims, Florida
Car: '87 IROCZ
Engine: 395 ZZ4
Transmission: ProBuilt 700R4
Axle/Gears: 9 bolt 3.70s
Sorry, I dont see the nut. I do see a good sized bolt.
Is the nut on the inside?
edit: your engine bay is alot cleaner than mine!!!!
Is the nut on the inside?
edit: your engine bay is alot cleaner than mine!!!!
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I spent a little over an hour, drive time to the muffler shop that did the weld included. Not that hard to take the plenum off, remove a few bolts, weld, paint, reassemble. Maybe if you want to add in the time to pick up the diphragm (had that laying around, replaced it for GP), time spent going down the street to OSH for bolt and nut... ok, couple hours. The Holley FPR (nicest one available IMO) was not on the market. The other versions did not include a diaphragm, are prone to problems (vacuum line breaking off) and are expensive, much more than my .10 bolt and .25 quarter. I could have left the old diaphragm, it was likely ok I just figured since I was there...
Supreme Member
Joined: Aug 2001
Posts: 1,337
Likes: 26
From: Wesley Chapel, Florida
Car: 1991 Camaro Z28
Engine: Dart SHP 406ci T88 turbo
Transmission: T56
Axle/Gears: QP 35 spline Ford 9" 3.50 gears
Originally posted by doc
Sorry, I dont see the nut. I do see a good sized bolt.
Is the nut on the inside?
edit: your engine bay is alot cleaner than mine!!!!
Sorry, I dont see the nut. I do see a good sized bolt.
Is the nut on the inside?
edit: your engine bay is alot cleaner than mine!!!!
Supreme Member
Joined: Jan 2003
Posts: 2,133
Likes: 4
From: Houston, Texas
Car: 88' IROCZ
Engine: 388 TPI Motown 350 Race block
Transmission: 700R4
Axle/Gears: 2.77
I did the mod, but wasn't satisfied with it. I was replacing the stock fuel ines with 3/8" stainless steel tubing, so I bought the Holley. I had to make some changes to accomodate the ss tubing and SwageLok fittings.
1.) Removed all stock tubing and retaining hardware.
2.) Replaced fuel rail alum cross connecting tubes with SS.
3.) Rotated the base parallel to the fuel rail increasing the clearance between the plenum and the top of the regulator. There are 2 alignment pins between the base and fuel rail.

1.) Removed all stock tubing and retaining hardware.
2.) Replaced fuel rail alum cross connecting tubes with SS.
3.) Rotated the base parallel to the fuel rail increasing the clearance between the plenum and the top of the regulator. There are 2 alignment pins between the base and fuel rail.

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Joined: Apr 2002
Posts: 514
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From: Deer Park, N.Y.
Car: 1983 z-28/SFC/bilsteins/adj.arms
Engine: 355sbc/Demon650dp/hedmanheaders/
Transmission: t-5, alum DS
Axle/Gears: 3.42 torsen posi, baer discs
super install, rgarcia! very neat,,,,,did you also mount a fp gauge? what pressures are you running and with what injectors? ( 19 or 24#? )
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