Fuel System Upgrades

[jim@foreignaffairs]

I get a lot of calls from people regarding fuel system upgrades since I have done quite a bit of R&D on the subject, so I thought I would spend less time on the phone if I wrote a quick update on what I have done so far and the results.

Many of you have installed the Foreign Affairs fuel system upgrade already, which is good. No one has ever sent one back saying it didn't improve their S/C car's running. Naturally my car has the same basic unit all of you have, though in addition, mine uses a Bosch fuel pump mounted outside the tank, an exotic fuel filter, a Aeromotive fuel pressure regulator and a return style fuel system. I have gone back to stock injectors and they work great.

I run 8 psi boost, (with lower compression high flow heads) but my car is meant to be a daily driver, pass DEQ testing, and be happy on pump gas.

Most of you who have kept up with all my fuel system R&D already know this, but what I haven't talked about yet was the fact that the Aeromotive regulator (which is adjustable from about 20 psi to 70 psi) also has a boost reference port on it that is quite handy for adding just the right amount of fuel pressure during boost conditions. Our cars don't see the mammoth amounts of boost some 4 cylinder cars do, commonly 14-25 psi and more. But it is still a good idea to compensate for boost with fuel pressure increases because boost at the tip of the injector pushes against the fuel trying to come out of the injector and leans out the mixture. Most stock cars for many years have had a vacuum line on the fuel rail mounted pressure regulator to do this very thing. You can add just the right amout of pressure to compensate for boost or vacuum changes by having a fuel pressure regulator that increases fuel pressure to compensate for boost. Putting in big injectors therefore isn't necessary, (until you get into a lot higher boost) nor is exotic electronics, they get expensive and are hard to dial in, and even then they don't do all that much if anything.

Now I know most of you don't have such a fuel pressure regulator, (our cars came with in tank regulators with no manifold pressure reference) but after doing some dialing in I have to say it is the way to go. My car has much better power with the boost port hooked up. I'm running about 48 psi fuel pressure at idle and at full throttle it goes up to 60 psi. Power comes on stronger and smoother and I can't wait to dyno the thing again. It just drives and feels SO much better! It made a big difference in low end responsiveness and midrange torque, top end power is better too, and it is not that hard to do. It was as much an improvment, if not more, as the basic fuel system upgrade a lot of you know is really good.

If it sounds like something a lot of people would be interested in, I can write again how I installed the system in my car, so you can do it yourself. While I used some of the most expensive components, there are lower cost alternatives that would work just fine. So give me feedback if you are interested, I may even put together a do it yourself kit if enough people are interested.

[krook]

i think someone already wrote up a DIY for the Foreign Affairs fuel kit, but i'd rather have a DIY straight from the horse's mouth.

hit us up with it please!

[DatSRBoi]

I agree. Sorry man, Im still trying to send you the money. I wish you could take paypal. No place takes money order with credit cards

[Ian]

I'm interested. Instructions and a kit would be great.

[StockSolara]

I'll be interested on the work it takes to do this

[Akfahad]

Jim,
You've caught my attention...What's your car at now, in terms of power? Let us know what she does after the newest dyno?! Also, if you did put together a kit, just off the top of your head, what are talking about in terms of price?

Josh

[CASTRO]

VERY interested Jim. Please do a write up and maybe suggestions on exact parts we should use. Id be willing to pay for a setup kit like the fuel lines since I want to make sure everything works together.

[jhenty]

you have seriously caught my attention. I'd be very interested in a DIY kit and write up. I'll be contacting you soon jim, thanks for this post it answered all my fuel questions.

[jim@foreignaffairs]

Well, for those of you interested in taking the next step in upgrading your fuel system, you will need to order up a few things. This is assuming you already have the basic fuel system upgrade already. All this stuff you can buy yourself and save money rather than have me send it to you. If you run into problems let me know, and I can gat what you need.

The brains of the system is the Aeromotive fuel pressure regulator. You can get it from Summit Racing Equipment (SummitRacing.com). The part number I used is AEI-13109, cost $134.95. With it you need to order two (2) -6 size fittings for the high performance -6AN fuel lines you will be attaching to it.

You will want a high flow trick fuel filter. I used a Golan (GolanProducts.com) filter #32-06AN which comes with fittings already, but you can save some money and get #40-06AN which is still servicable, looks trick and is better by far than any stock filter I know of. There are other filter available as well, basically you want an excellent quality in-line filter you can attach -6AN fitting to.

The last item for now is the fuel pump. That's the heart of the system. I used a Bosch 0 580 254 910-390 model pump. The will be mounted outside the tank in front of the left rear wheel. You will need to fabricate a bracket to hold it under the car if you use this pump, I used an old ignition coil bracket I found around the shop. You can also use any pump rated to deliver at least 60 psi. The Bosch pump can deliver about 75 psi. This pump is used by a lot of racers I have noticed.

When you have your stuff, let me know and I will tell you what to get next, or call me any time 8-4 pacific time.

Jim
Foreign Affairs
503-236-2871

[CASTRO]

hey jim, is there any way this could work with the lines and filter kit we got from you? I'd be a shame and a lot of work to just take it all apart for the new stuff. Seems like from the post, if we had the previous kit, we would just need the pressure regulator as well a bosch external pump. Would those be a direct bolt on too or would any cutting/modifying need to be done to the stock hard fuel lines. Sorry for so many questions.

[DatSRBoi]

Hey Jim. I currently have a 190 walrbo fuel pump. Will I still need to buy that fuel pump you said too? And is tuning required or is this a plug and play?

[jim@foreignaffairs]

Good questions. The last first: For the most part it is plug and play as it would need no tuning, you may have to "undo" some of the fuel trims you used when your system was less powerful.

This system uses no internal fuel pump, so the Walbro will not be used.

We will use the lines I sent you already, but the new filter will be a big improvement. You can use the filter I sent, if you would rather. It will probably work fine, just change it more often.

There is no cutting or modifying of lines, it can be put back the old way if you want without replacing parts. An additional fuel line is run. The original fuel line is used to RETURN fuel to the tank. So we don't waste it. It is working for us.

In order to do this system, we have to tap into the fuel tank with a new bigger fuel line. That new fuel line pulls fuel out of the tank to the pump, then forward along the frame rail up to a filter, and to the regulator.

The fuel system I already sent you is attached to the regulator at that point. The original fuel line is attached to the regulator's return port which returns excess fuel to the tank.

[trd4life]

ahhh now i see how you did it Jim! I remember we talked about 6 months ago on the phone about your setup. I ended up doing mine a little different. I tapped the ends of the fuel rails, back to a reglaotr, then to back to the tank after the rails. I kept the intank walbro 255 but also ran a -6 feed line to replace the stock feed line, while i was at it, i added an additional walbro 255 inline.

I use the same Aeromotive regulator as you set at 30 psi using 400cc injectors. I had to lower the FP way down to get a good idle with the massive injectors, i am temorarily using an safc for tuning.

[DatSRBoi]

Im sorry, Im alittle slow. Im trying to get this down as serious as possible...

So basicly let me get this straight. We're going to disconnect the hose from the stock pump in the fuel tank and let that be the return flow hose there right. and we have to run a new hose from the tank to an external fuel pump rated at recommendation psi. which from there runs to another new hose all the way up to the fuel filter . Then it goes into the regulator and spilts out into the two lines which each goes to its own fuel rail... So with this we shall have a return fuel system?

I accidently ordered my 190 walbro fuel pump before you made this post.. Is this pump rated 60psi? And is there any way you can create an idea to use pump if its 60psi? I was wondering if that was possible or something to run the walbro 190lph and use the stock fuel line to go to your jim fuel filter, then regulator where it splits to the two fuel rail. and run a separate hose as the return fuel to your fuel tank......... Will that work? Or am I putting myself into danger because its not strong enough or the fuel line isnt big enough? Max Ill ever run is 5.5 psi pulley.


Also I went to the shop today and ask about the fittings thing -6ans like you said.. Then they asked me what type of thread? They said there are two types for imports? Can you tell me exactly which one Im looking for. Because they wanted to charge me 200 frieken labor bucks just to find out for me...............

[CASTRO]

for the fuel additional fuel line from the tank to the fuel filter... I think i know the answer to this, but is it steet braided vs. a hard line like stock?
And would length of the line be an issue when I do order it?
Would the extra line come prefitted with the fittings the same way your first fuel line kit came, or would it all be separately assembled?
About the hose/tapping for the additional fuel hose from the tank, do you think you can go into detail on how that would be done?