Fun(?) with trying to install twin Hellcat fuel pumps.
Thread Starter
Joined: Feb 2003
Posts: 2,145
Likes: 133
From: East Chatham, New York
Fun(?) with trying to install twin Hellcat fuel pumps. I went to the strip last month to try and start getting some tuning data with the S480 Turbo at Lebanon Valley's strip. First pass, got a miserable 1.89 sixty from spinning the 315 DR's with just 3 psi on the brake. The middle of the track felt pretty good but then it started breaking up a little so I got out of it. Turned a 10.5 at 108mph. Back in the pits , I pulled up the log and saw that my digital fuel pressure sensor was showing my boost referenced FPR was only seeing 4x psi when the breakup was manifesting. I had twin 340's in the tank, feeding E85 to the Bosch 210 injectors. I sighed, then drove home, resolving to put in twin Hellcat pumps.
Pulled out the stem with the twin 340's and dismounted them. I had ordered the Hellcat pumps and had them beside me as I envisioned the arraignment and fitment. I had the rubber gasket from the pump 'hat' and could readily see that if I had both pumps side by side, they wouldn't make it thru the orifice. I decided to mount the one pump solidly, then made a bracket and apparatus to allow me to insert the stem/tree half way, then while holding that with one hand, I could slide the second pump onto my bracket inside the pump, secure it with a bolt and viola, it worked! But... then trying to insert it fully into the tank. Whoops... damn it. There's a bit of construction (baffles? Plastic walls with a channel in it for one pump or two pumps (the 340s) if small enough in diameter) in the bottom back of the tank that won't allow the assembled pumps to slide in.
I've come up with a second design and will try that tomorrow.
Pulled out the stem with the twin 340's and dismounted them. I had ordered the Hellcat pumps and had them beside me as I envisioned the arraignment and fitment. I had the rubber gasket from the pump 'hat' and could readily see that if I had both pumps side by side, they wouldn't make it thru the orifice. I decided to mount the one pump solidly, then made a bracket and apparatus to allow me to insert the stem/tree half way, then while holding that with one hand, I could slide the second pump onto my bracket inside the pump, secure it with a bolt and viola, it worked! But... then trying to insert it fully into the tank. Whoops... damn it. There's a bit of construction (baffles? Plastic walls with a channel in it for one pump or two pumps (the 340s) if small enough in diameter) in the bottom back of the tank that won't allow the assembled pumps to slide in.
I've come up with a second design and will try that tomorrow.
Thread Starter
Joined: Feb 2003
Posts: 2,145
Likes: 133
From: East Chatham, New York
Update: Got them in. First setup leaked as I did a poor job of converting the Vent line to a second feed from the 2nd Hellcat pump. I'd bought a stock fuel pump assembly awhile back so I took it apart and used it for a 'donor'. I also drilled and afixed 4 'bulkhead' connectors. One supplies all grounds, One for Pump#1 (fulltime pump) , one for the Hobbs actuated Pump#2 and the last one for the fuel level feed. Unfortunately, racing season here in upstate NY is over (Lebanon Valley), so, next year. I did get out a few times this year. No new bests as traction was an issue, plus, the aforementioned leaky setup was running out of fuel at full tilt. I took down a Ford lightning (probably late 90's model) that murdered me off the line. I flew by him several feet before the finish line with his MPH at 112 and mine at 131mph. I also got to race a Tesla Plaid. I thought I'd be able to show him I could keep up but dang... he flew off the line while I was back there spinning both off the line and at the top of 2nd. He turned a high 9 at 142'ish. Respect.....Next season, I won't be on the DR's the whole time and use my 28" Hoosier slicks.
