I want to get your opinion on this combination. First, the reason for such an unusual combination. I was given this Hilborn pump off of an early top fuel dragster with instructions to find a way to use it if I could. It was originally on the late Johnny Lopers (Lopers Phoenix Speed Shop owner) top fuel dragster back in the '60's and early '70's. It was given to a friend who worked closely with Johnny at his shop. The friend wants me to find a way to use it instead of it sitting on a shelf collecting dust. With that said. I want to try to use it on the car I am building. It's a street/strip Gasser type street freak. 1960 Pontiac block .090 over. All new forged bottom end. Forged Ross dished pistons, aluminum GRP rods, splayed 4 bolt center caps, steel rod inserts from the center decks down into the waterjacket bottom for deck support, etc etc. So it is a well planned/serious short block for the task, not a throw together set up. I will be running twin 76MM turbos, twin air to water intercoolers, twin 750 blow thru CSU carbs on a Wenzler Tunnel Ram. All this is set up for pump E-85. I am shooting for a normally lower 1000 HP with intent to raise the boost under controlled situations for 1500 or more HP. I need a good fuel system. So this is my plan. Feel free to guide, critique, and or shoot me in the head if you feel that it's just not doable. If I cannot use it as a pump I have an alternative plan too.
This is the "NOT" set in stone plan starting from the back of the car. I have 26 gal alum fuel tank from a boat (I have). I'll add a simple low pressure electric pump only to feed a front mounted Moon 3.5 gal surge tank ( I have). This Moon tank already has a provision welded on for a Holley fuel bowl. I also hope to install the tank close to and above the pump inlet to aid fuel flow. The pump is already mounted on the engine with a Moon front timing cover, cam driven using a custom made adaptor to use a BBC drive spud. The surge tank will be plumbed with AN -12 line to the pump. The pump is equiped with a shutoff/bypass valve on the outlet side, using AN -8 line/fittings. I plan to run the outlet side to an Aeromotive bypass 4 port regualtor set at 6-7 pounds, AN-6 lines to each fuel bowl. The bypass is to return to the surge tank thru a small air to air finned cooler if needed (to fight any fuel heating from the pumping and returning).
I know the pump will provide plenty of flow for my needs. The regulator should handle the flow to the carb bowls, and bypass the rest. The outlet -8 sized line is what they used on it for the fueler so I feel that should be fine. My questions are:
1. Am I nuts?
(Likely, yes).
2. If it is doable. Are my plans OK or do they need major revamping?
3. I wonder if the bypass from the regulator is better returned to the surge tank or to the inlet of the pump?
4. Do you think a carb based fuel regulator will be able to handle the higher RPM pressure profile of the pump to bypass and not flood the carbs?
5. Do you know if the pressure profile is such that it will not unduly stress the pump under idle and or cruise conditions? Meaning, if the pump profile, at say 3000 rpm cruise, is already making high pressure, will that hurt the pump for longer run times such as a drive thru the city. Or a steady state freeway/highway run of 30 to 60 minutes without a stop? I'm trying to determine if the pump will handle this kind of environment. Since they're really designed for short high pressure runs. I mentioned the original bypass valve after the pump outlet because I could see during a cruise where I could actually run a manual cable to the bypass and open it for a bypass back to the rear tank to lessen the pressure and stress during a long cruise, plus that fuel being pumped and heated could return to the rear tank instead of the surge tank. Keeping the surge tank cooler.
I mentioned an alternative. If the pump just is not a good candidate for this kind of use, then I thought mounting the pump without the cam drive attachment. Then run a strong electric (Aeromotive A1000) pump under the surge tank, but plumb it thru the Hilborn pump with pump, fins removed to allow flo thru. The rest after the pump would follow thru.
Well I hope I didn't leave anything out. Sorry for the long (possibly boring, lol) description. Everything hinges on the pumps ability to work within these confinments/requirements. Plus it's longevity as a viable pump for many more miles than it was originally designed for. I have seen others using it for the street but they always had it on a real Mechanical Fuel Injecton (non forced induction or carbed) system set up almost exactly as designed. I also don't know what kind of miles their pumps sees.
Thank you Spud for your time and expertise on this matter. It is much appreciated.
Mark L
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