Chuck and Ryan's RCR Build

[Chuck]

Bulkhead Preparation

In an early post we noted that the car was ordered with “wings” or bulkheads located either side of the fire wall. We spent a lot of time laying out the location of the fuel pumps, coil and expansion tank. Our goal was to eliminate as much visible wiring and make the fuel system as simple as possible. We wanted to conceal the primary fuel filters behind the bulkheads. Full size patterns were drawn and revised several times as we experimented with the spacing.

We wanted to be able to easily access the filters and electrical connections hidden behind the bulkheads. Although the bulkheads can be removed after the spider is in place, round access ports were added, using plates from AERO TECH LABS, part # TF107. They are about 4 ½” in diameter. They are pricey, but the gold alodine finish adds a nice touch and they are large enough to provide good access. The screw holes were drilled and tapped.

The small tank on the left rear was opened and an oval cover plate, approximately 6 x 9 inches from AERO TECH LABS, part #TF110A was used as a cover plate. Inside this area the gaudy bright MSD ignition module will be located where no one will ever see it, along with the fuel pump relays and other electrical parts.

A layer of rubberized insulation / sound dampening was placed on the back of the firewall, which will be concealed by the bulkhead. Rubber grommets were placed where the fuel line and wires will pass through the bulkhead.

An aluminum angle bracket was secured to the chassis to hold the lower edge of the bulkheads in place. Holes were drilled just aft of the fuel tank (There is about ¾” between the back end of the fuel tank and the bulkhead – just enough space to secure the screws to hold the aluminum angle bracket.) Two six inch long by 3/16” screws were then run forward to the firewall to pull it back into position on each side.. Without these screws there is a lot of tension placed on the spider by the firewall.

[Chuck]

Fuel System

The location of the sending units was carefully planned, so that they would be accessible from the access panels on the bulkhead and not interfere with the support brackets. The primary hole was drilled and five small screw holes were drilled and carefully tapped. The sending units were assembled, flipping over the electrical float sensor (which we discovered were upside down when we tested the units while wiring the dash).

Holley HP 125 fuel pumps were selected. They are likely more pump than needed, but have some noteworthy features. They use a gerotor type pump and thus should be quieter. There shape is suggestive of the original style pumps. But most important, the black and polished finish looks cool!

Holley in line fuel filters were connected between the fuel pick ups and the fuel pumps serving as the primary filters. They are small and compact and fit neatly behind the bulkhead. These filters will likely be replaced early on, since they will pick up the bits of debris in the tank left behind while building the car, despite every possible effort to keep the tanks clean. They can be easily accessed through the bulkhead access plate.

To prevent back flow of fuel Aeroquip check valves, AN-06, were added between the primary filters and the pump. These are also concealed behind the bulkhead.

Some may wonder why we used such an obscenely large fuel filter: a Perma Cool fuel and water separator. First, it has input and output ports ideally suited to the GT, with two inputs each on opposite sides. Second it is a high volume filter with fine filtration (25 GPM and 2 microns). Third, it is also a water separator (a feature of limited significance, but cool none the less). Fourth, the filter element has a long life (24,000 miles) and is easily replaced. Fifth, it fits neatly in the space available. The filter shell was painted our usual low gloss engine black to make sure it blended in with the other hardware. (We use this color for just about everything that is painted black. It matches the power coated chassis perfectly).

A Holley pressure regulator, 510-12-804, (1 to 4 PSI) was installed, since the Weber’s are a bit fussy about excess pressure. A Holley pressure meter was installed on the opposite side of the regulator where it can be easily seen

The section of fuel line running from the right to the left side was secured to the base of the firewall opening and insulted with a reflective sleeve type covering.

A Canton aluminum expansion tank was mounted on the right bulkhead. Thick rubber washers stand it a quarter inch off the bulkhead. I will discuss ideas for plumbing the tank in a later post. The fiberglass battery cover is visible below the expansion tank in the photo below.

Red and blue AN fittings with stainless hose is certainly authentic and probably the safest way to go, but we liked the look of the traditional fittings and black hose used in the earliest GTs, so that is what we used. Aluminum 3/8” tubing was used for the longer runs, secured in place with cushioned hose clamps.

The aluminum tubing was cut and bent to fit. The ends were dressed with a fine file. We then added a bead to the ends to make the hose connections more secure with a clever little device, Earl’s EZ Bender, 40-008ERL, shown in the photograph below. Mother’s Billet Polish is great stuff that gives the aluminum a mirror like finish. Short lengths of 3/8 inch rubber hose were then connected the tubing and the adjoining connections. Hose clamps will be added later, once we are sure everything is in the right place.

[Fran Hall RCR]

Chuck..that is absolutely stunning.

[Pantera1889]

Chuck,
You guys are doing an incredible job!! Everything looks VERY professional.
Not to rain on your parade but I have traveled down the road you are traveling with your fuel system and I encountered a few problems.First,I added the exact same check valves that you have.I couldn't get fuel to flow through them no matter what I did.The release spring inside is much too strong for this type of fuel pump.I removed them and the pump primed itself almost instantly.
Second,I originally used a Summit brand 140 gph pump.That pump started leaking so I replaced it with the Holley pump that you have.It wouldn't pick up fuel from the tanks no matter what I did! I could manually prime it and it would work ok but if I shut it off for a few minutes and tried again,nothing! I replaced it with another Summit pump and all has been fine for the past five months.
I hope this helps in some way and maybe saves you some headache later.

[Chuck]

Hey Ron:

Thanks for the heads up. I know what you mean about the release spring being strong in the Aeroquip check valves, and that was a concern. Did you use a different type of check valve? If so, what brand and model?

Did you try modifying the spring to reduce the resistance on the check valve?

I also noted some differing opinions as to whether the check valve should be on the output or input side of the pump. Most seem to recommend the input side.

Thanks for the heads up on the fuel pump as well. I wonder if an effective check valve were between the pump and the tank if that would keep it primed? Seems odd that a pump like that would not be able to lift the fuel only three to ten inches (depending upon the amount of fuel in the tank).

Obviously I have not yet check the fuel system with fuel yet . . . . Thanks for your input.

Chuck

[Scott Calabro]

Hi Chuck,

Aeromotive, Earls and Fuel safe make check valves, in addition to Aeroquip.

Holley Performance Products Check Valve*251006ERL

I think Weber does too.

Cheers,
Scott

[Big-Foot]

Guys - I agree with all on the stellar job you're doing on your build.

I've covered this elsewhere but was unable to find it in the search so here goes again;

Diaphragm or Gearotor positive displacement pumps are best used in a lifting situation.

I'm planning on using a pair of these pumps by Purolator-Facet. They are made to lift fuel up to 10 feet and don't require either check valves or priming. They're not cheap but they're not going to leave me sitting there wondering how to get my car started.


The best (cheapest) place I've found them is Aircraft Spruce;
05-0082940223 PUROLATOR DURA-LIFT$140.950
Pilot Supplies, Avionics, and Homebuilt Aircraft Parts from Aircraft Spruce and Specialty Co.

They are also sold under the Thermo King brand name for use in Truck Reefer units that have to pull fuel from the truck's tanks all the way up to the Reefer engine.

More specs:
Dura-lift pump

Features:

- Self-priming with a 10 ft. (3m) lift capacity - Built in check valve to prevent back flow
- 4 hour dry run (how good is that!)
- 80 micron serviceable filter
- 30 GPH
- 9 to 11.5 psi
- SAE J1455 Certified
- Transient protection
- State of the art sealed electronics
- Reverse polarity protection
- Corrosion resistant: over 1000 hours salt spray
- Durable transparent fuel bowl
- Light weight - 3LBs (1.3kg)
- Height 7 1/4” "(180mm)
- Low power requirements - 1.4 amp average
- Self regulating (No regulator needed!)

Hope this is of some help... Please keep up the fine work!!!

[Dean Lampe]

Chuck, I am fighting the same gremlins with the Aeromotive check valves. It is very frustrating. I have 6 holley pumps in my garage now with 2 of those check valves. I should have bought better pumps the first time now I have about $800 in fuel system parts that are second rate! I will probably switch to those pumps.

[Keith Hardy]

Would the min pressure (9 psi) be a little high for carburated applications?

PS, nice pump

[Big-Foot]

Keith - I would run a return-style pressure regulator to drop the net pressure to a more appropriate level...

Dean - I think the Purolator-Facet pumps would end all your troubles..

[Bill D]

Chuck and Ryan
Your progress and attention to detail is inspirational!! I can't wait to see the final product.

Question:
Where does the hose from the Canton surge tank hook up on the engine?

Thanks
Bill D

[Rob]

Hey Chuck and Ryan...
Frankly.... I'm getting tired of telling you guys "nice work", so .... I guess I'll say "excellent job" this time.... Seriously, as Ron stated your work looks professionally done. Kudos.

The Earls check valve in my opinion is the one to go with. It is designed for military usage, it is a flapper style valve, w/o heavy return spring to overcome. This is what I am using, after much research.

My only other comment is you may want to confirm your rear fuel loop will clear your rear clip.

Keep on rockin....

[Chuck]

Fuel Pumps Revisited

Ron McCall’s post prompted us to check the operation of the Holly 125 fuel pumps and the Aeroquip check valves; something we should have done while we still had the purchase receipts. It is a good thing we did.

The pumps worked great. They really sucked. With the bottom of the intake hose 19 inches below the intake on the pump (as low as we could get it without removing the pump from the car) it put out a stream that would make a Flowmax commercial proud.

Then we inserted the Aeroquip check valve in the intake line. Nothing. Then the output line. Nothing. Ron was right.

The Aeroquip check valve has a ball held in place with a spring. A red insert holds the spring in place. It seemed that if the insert could be backed out it would reduce the tension on the spring and thus reduce the resistance. Lacking a proper tool, we ground the edges off a ½” butterfly bit to make it fit. With a lot of effort we finally were able get the red insert out. Sure enough, the distance the insert is screwed in has a direct affect on the tension on the ball. In our application, the easiest solution was to just leave out the red insert and then stretch the spring until it just kept the ball in place with the fitting we were using; just enough tension so one could not hear the ball rattle. Now we could easily blow through it one way, but not the other.

We reconnected the check valve and tried it again. It worked perfectly. Same strong stream, same 19 inches of lift, and same result on both sides. Problem solved.

Special thanks to Ron for alerting me to the potential problem and the helpful comments of everyone. I cannot imagine undertaking a project like this without the internet..

[Chuck]

Randy: I suspect the Facet pump would be one of the best functional choices. After all, they are made for use in aircraft, so they had best be relaible. Aircraft Spruce also sells smaller Facet pumps that looks just the those used in the early GT's before the Stewart Warner pumps. The were sometimes mounted horizontally, two side by side. But they lack the features of the one you have selected. And by todays standards they may be marginal.

Bill: the 5/8" hose coming off the bottom of the Canton tank goes to the 5/8" intake on the water pump. it is visible in the picture I posted from the firewall side.

Rob: Your comment about the fuel loop on the left side clearing the rear clip is an excellent observation, which I had not considered. But the bulkheads are set in a good inch from the lip around the edge of the spider and the loop does not extend out that far, so it should not be a problem (I hope).

Keith: We have a pressure regulator between the fuel filter and the intake to the carbs to keep the pressure around 2 or 3 pounds. It is just barely visible in the pics.
Ra

[Pantera1889]

Chuck,

That is GREAT news about your pump! It is a beautiful pump and VERY quiet!
I guess I may have gotten a dud.(not the 1st time)
I thought about doing the same thing to my check valves but didn't want to screw them up.They are pretty expensive and they were on the small side for me anyway.
I have since replumbed my tanks to a common switching valve with no need for a check valve.It is the most simple setup I could come up with and it works great.


I'm glad I could help.

P.s. If anyone needs a set of the check valves,let me know! I will make you a great deal!!!

[Big-Foot]

Chuck - Guys - The Holley HP series pumps are also Gerotor design and as Chuck demonstrated are capable of functioning as "Lift Pumps".. Combined with your modified Check Valve, I'll bet you'll be in fine shape...

[Bill D]

I'm using these low pressure flapper check valves from Pegasus Auto racing