Fuel System: '63 Super Hawk - Boost Reference Port Question

[High_Noon]

I have been a Studebaker Driver’s Club member since about 1984, but I am new to the forum. I have a ’63 Super Hawk that I do not drive very often at all. The problem I am experiencing is that the fuel evaporates from the carburetor bowls and I must prime the carburetor manually, which as you can imagine is a PITA, especially since it’s supercharged.

Many years ago, I added a small electric pump to help resolve this issue, but this old electric pump does little if anything and I plan on removing it.

I recently ordered a Holley Blue electric pump, Billet By-Pass regulator, a delete plate/gasket, a ½” spacer (that will be placed between the top of the carburetor and the supercharger top cap) and a fuel pressure gauge. I plan to address the return fuel line that runs off of the fitting at the top of the original R/2 mechanical fuel pump with this Billet regulator: https://www.holley.com/products/fuel...s/parts/12-879. Although I would prefer a Mallory set-up, I believe that the Mallory kits are overkill for this application, not to mention that they are substantially more expensive.

I believe I have the “equalizer line” issue sorted, but I wanted to see if the members here agree with my plan: The 1:1 Boost Reference port (a feature of the Holley Billet By-Pass Regulator) has a brass fitting at the top of the regulator (which I linked to above) that I plan on running between the regulator and the 1/2" spacer (I will drill and tap a brass fitting into the spacer). This way, the vacuum line will be on top of the carburetor and between the top of the carb and the supercharger carb top cap. The 1:1 Boost Reference of the Holley regulator should properly address the Equalization Line issue. One of my concerns was the screened breather hole with internal flap that is on the top of the carburetor-supercharger top cap – that it might interfere with the vacuum of the 1:1 boost reference port feature of the Holley Billet regulator – but the Holley tech dept. told me that would not be an issue. The return fuel line at the bottom of the Holley regulator will be utilized for a return fuel line back to the tank and will properly address that issue. I plan on mounting this regulator by using a bracket at the location of the mechanical fuel pump delete plate for a neat and easily accessible installation.

So, what say you regarding my plan? Thanks in advance for any advice.

[bezhawk]

That valve on the carb bonnet is closed at anything above idle, so you should be fine. You could also just run a line from the stock fitting on the supercharger to the boost reference port of the regulator. same difference.

[High_Noon]

bezhawk: Thanks for the reply. I will look into that.

[doofus]

Hi, Noon, your "equalizer line" is actually a reference line so the fuel pump will keep pressure a few pounds above "Boost Pressure". My old R/2 mech pump has worked at 18 Lbs and survived ( The Head Gaskets Didn't,) the key to carb priming is Drive it more often, simple. enjoy your work and let us know how it works out. Luck Doofus

[High_Noon]

doofus: Thanks for the reply. Yes, driving it more often resolves the carb. priming issue; however, I am unable to drive the vehicle regularly as it's stored hundreds of miles away from me and has been for the last 8 years. I try to get my brother to drive it every few weeks but he rarely does so both due to his schedule and the fact that he doesn't want to fool with priming the carb every time he drives it. At 80, my Father cannot open the hood any longer due to its weight. So, easier said than done. Hopefully, I'll be able to bring it to my location soon.

[doofus]

So, up the creek and no paddle. in that case i believe you are on the right track. enjoy the supercharged performance! Luck Doofus

[High_Noon]

I've been working on the project for a few hours a day for the past 2 days, because it's quite hot and humid here. I probably have one or two days of work left to complete the job (a few hours a day). The biggest challenge so far has been to find a suitable location for the Holley Blue fuel pump, since it must be mounted low and fairly close to the fuel tank. I found a location for the fuel pump, but the screw-in 85 micron filter that screws into the pump is within a few inches of the left rear shock and also within a few inches of the muffler, but I really cannot find a better place to mount it. I will post some photos when the job is complete.

I have also mounted the Holley Billet By Pass Regulator, which I ended up mounting on the inner fender, since the mechanical fuel pump was much lower than I remember and even with the delete plate, it's an entirely unsuitable location for mounting the regulator.

I also decided to run the boost reference (equalizer line) from the port on the supercharger to the regulator, as bezhawk suggested above, which was how it was originally run to the mechanical fuel pump.

More to come.

[High_Noon]

Installation is complete. When I finished I ran up to the service station to get 5 gallons of fuel, poured it into the tank, turned on the ignition, waited 30 seconds for the fuel pump to do its work, turned the key and it fired right up! The only issue is that the fuel pressure gauge that I attached to the Holley Billet By Pass Regulator is showing 13 psi and it should be 5 psi. I adjusted the regulator pressure valve all the way out and it still shows 13 psi. I will call Holley technical support tomorrow. If anyone has any ideas on how to trouble shoot this issue I would be very appreciative. Below are some bad mobile phone photos. The vehicle is dirty:


Holley Blue Fuel Pump (that's one of the mufflers on the lower left of the photo):



Holley Billet By Pass Regulator:



Engine w/ Supercharger:



Front Left Quarter:



Rear Left Quarter:

[High_Noon]

Regarding the fuel pressure problem, I contacted Holley and they think that the Billet Regulator has a bad diaphragm. They are overnighting me a replacement unit.

[DEEPNHOCK]

A Holley Blue pump is a race pump.
Loud, noise wise, and requires a regulator to get the PSI down to the carb level.
Not badmaouthing it, but it is overkill for your setup.
A slightly smaller electric pump, with a regulator and a return line would solve all your problems.

Oh, and put a heat shield on that pump.
It is close to the muffler.

[High_Noon]

DEEPINHOCK: Thanks for the reply. Yes, I realize that the Holley Blue is a racing pump, and is likely a bit overkill for this application, but the Holley Billet By-Pass Regulator is adjustable from 4-65 psi, (it also has a return line and a by-pass port/equalizer line). The regulator comes pre-set at 7 psi, so it should be a relatively simple procedure to set the pump at 5 psi. As far as the noise, it's perhaps just a bit louder than other electric pumps I've tried, but I like to hear the noise so I know it's working. The smaller electric fuel pumps I've tried have not really worked properly on the Hawk - especially not being strong enough to prime the carb., since the vehicle sits for long periods of time - the Holley Blue certainly alleviates that problem. For these reasons, I decided, and was recommended, to use a Holley Red or Blue pump.

I agree with your assessment that a heat shield is needed for the Holley Blue. What would you recommend?

[DEEPNHOCK]

<snip>

I agree with your assessment that a heat shield is needed for the Holley Blue. What would you recommend?

Here's my idea for a Whoosh-Bonk heat shield. (A Bruce McLaren term)
Pick 3 of the bolts holding that bottom plate on. Just 3. Make it a triange.
I'd get 3 bolts that are about 1/2" or maybe 5/8" longer than the end plate bolts on that fuel pump. Get some small aluminum spacer sleeves, say about 3/8" to 1/2" long, same ID as the bolts. Fab up a small aluminum piece of sheet metal (stainless if you want all fancy). Drill 3 holes to match the Holley end plate. Put a bend on one end of the plate so it clears the muffler. (Half way between the muffler and the pump)
Bolt it on... You are all done.
Just thinkin' out loud..

[High_Noon]

DEEPNHOCK: That could work - maybe stick on some Dynamat for extra insulation as well. Thanks.

[Xcalibur]

I missed one of your posts above when I originally replied... sorry. Comment was irrelevant if it is essentially working. All the best.

[High_Noon]

I built a heat shield out of galvanized sheet metal. It's a box that covers the bottom and three sides - should work well.