bubafett

The only question that I have...

Is the best way to regulate the factory fuel pressure down and still use as much as the stock fuel lines and pump etc and return lines.

I know I need a regulator. Where do I put it, how do I attach to the steel line, which fittings do I need, where to flare the line etc. and which regulator should I buy.

Fbird88

Well, different people have different opinions on this, so I guess I'll throw mine out...

Personally, I wouldn't use an AFPR when converting from TPI. TBI is another matter because the fuel pump is only putting out 15 psi. The TPI fuel pump puts out around 40 psi, and a few people have had problems (like the guy that wrote the TPI-Carb tech article) regulating it that down that far. In my case, I used an AFPR because I had TBI and the pressure difference was only 10 psi. Since you have TPI, I would do it the right way and drop the tank.

With that said, if you do decide to use an AFPR I woud mount it on the strut tower mount on the drivers' side. The fittings can usually be obtained from a hydraulic hose shop. You need 16mm-1.5 and 14mm-1.5. Hope this helps.

Mike :lala:

scauffiel

I used the Mallory to get from a TPI (the walbro replacement) pump down to a TBI, then down further to a carb. Works fine with zero problems so far (knock knock). Here's a pic:

EDIT: Wrong damn button - Look for pic in NEXT post.

Steve

scauffiel

Okay...

bubafett

Thanks for the help!

What is an AFPR.

I also dont know what BTW is.

I have however figured out WTF.

x5finger

AFPR = Adjustable Fuel Pressure Regulator

As I said in the article, I did have problems.
Any time I take the pressure to around 4.5 psi, I start hearing a muffled thunk-thunk-thunk noise. My fuel pressure needle starts bouncing back and forth rapidly. I have to take it down to about 4 psi to keep it steady. Also, if I let the fuel pump run it will start with the thunk-thunk noise. Goes away once I start the engine. <shrug> Still runs, though. Your mileage may vary...

To set this up, I was able to use most of the stock hardware. I left the stock on subframe hard line, the flexible lines, and the on engine hard lines. I just used a pipe cutter to take off the end of the blocks hard lines so I could slip on some rubber hose. I then (look at scauffiels pic for reference) added a 90 degree fitting on the bottom (return port), and another 3/8 hose fitting. I only had to use about 2-3 inches hose for either the flow or return lines. I had a spare hole on the front of my manifold, so I bolted it there. AFPR to carb only took another couple inches.

89formula#1

how exactly do u hook up one of those mallory 3-way afpr. i am gettin one for my tbi to carb swap. i am guessin the gas line goes into one port and then another line comes out and goes to the carb but were does the other line go? thanks

Blackened

Isnt it pretty obvious in the above picture ?!?

fordcrusher

It goes into that guys finger. Where do I find one of those guys? Seriously though, it looks capped off. Is it?

Fbird88

That's not a cap, that's where you adjust the fuel pressure. The front and back ports are plugged.

88IROC350TPI

I used the Mallory regulator. My only complaint is that the fuel pressure isn't very steady. It seems to bounce from 5-7 psi. No problems so far though. Not a very good picture but I have mine mounted on the strut tower and used lots of braided hose:

x5finger

88IROC350TPI: Those look like the stock subframe to engine flex lines. What AN fitting/size did you use? Or did you just jb weld a fitting in?

For a really slick setup, check out edelbrocks regulator/mounting plate kit for dual feed holleys. A plate goes between the carb and the intake manifold, and a flage juts out on the fuel feed line side of the carb. A regulator mounts upright to the plate. Either side of the regulator goes to the fuel bowl closest to it. there is a 90 degree fitting on the underside of the plate/regulator that you hook the fuel feed up to. Would work for the mallory regulator, but you could fab up something yourself real easy.

-5finger

88IROC350TPI

Accel (310-74730 on jegs) sells adapters that turn the stock fittings into 6AN. They're not very cheap though ...like $30

Coxy

I just got the fitings from earls indy, they were like $5.50 a piece. They go right on the hard line and come out to a 6an fitting.

camarokev400

allright guys prob a dumb so dont jump on me too bad, but i just bought my mallory 3 port fuel pressure regulator and i was just wondering if it was really necessart to get this 3 port one... which actually has 4 holes and the return on it... i dont understand why i would need 4 holes i see how the line from the fuel pump goes into it and comes out a lower pressure but why buy one that has so many ports if you are only going to be using 2 of them... like the picture above i see that he has 2 of the ports blocked off... just a dumb question since i already bought it its a little late now

x5finger

There are many reasons, one of which being that this is just a regulator and can be used for many applications. Some people may have tight clearances or the routing may be easier using one of the other ports. Also, as opposed to running a single line out and adding a Y to a dual carb, or even a dual feed holley, you could just at another fitting to it. The majority of people only need the three primary ports, but adding the extra two gives the product a larger market at less cost (that saved aluminum must add up! hehe..)

-5finger
"the guy that wrote the TPI-Carb tech article"

my89formula350

WELL HERES MY 2 CENTS BOUGHT THE MALLORY AFPR ALSO HAD THE MALLORY COMP 60 PUMP WENT TO CARB NO PROB READ POSTS SEEMS LIKE SHOULD WORK ,NOPE PRESSURE WOULD NOT GO BELOW 10 LPS DUE TO SMALLER RETURN LINE WENT TO HALF INCH RETURN WORKS LIKE A PRO NEVER GETS OFF OF 6 LPS EVEN AFTER A HARD PASS

T-Tops

When converted to carb from my tpi,I dropped the tank removed the fuel pump and ran a new fuel line in the tank.Then connected the lines to a mechanical pump.Also removed the inline tpi fuel filter and put a inline carb. filter between the pump and carb.