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drgrumpus's Achievements



  1. No Megasquirt. We use stock ECU with custom card to customize fuel maps at WOT. The O2 sensor trim is deactivated. Spark plugs showed all 8 cylinders lean. Two plugs had tips blown off.
  2. Chris, very true. We run on an inertial "roller" dyno. True, not a good simulation of WOT, constant speed like banking at Daytona, but we use it for back-back testing. I think we will pull back to 32 degrees total advance and keep A/F at 12.1. We'll go with bigger injectors to get the duty cycle back to about 80%. Maybe re-activate the O2 adaptive function in the ECU. BTW, I have built 13.5 CR engines for sprint racing(not ford small blocks) and had to use 112 octane fuel. At $10 a gallon or more these days, that is not an option for us cash concious endurance guys.
  3. Compression ratio NOT 13.5. We run 9.4, just a tenth over stock. 34 degree advance at high rpm was optimum on dyno.
  4. Our engine was set up on the dyno at 12.5 A/F with O2 sensor adaptive loop defeated. I call it a fancy carburetor. Ignition set at 34 degrees constant above 3500 rpm. Engine geared to run between 3500-5500 rpm. Fuel pumps sized and tested to have 70+% excess flow at peak power. However, fuel injectors at 92% duty cycle. 93 octane fuel came from the Sunoco station on International Speedway Drive close to the speedway. Clean, capped 5 gallon fuel jugs. We have tested fuel pumps fuel pressure, and set an adjustable pressure regulator at 12.1 A/F for next race. Also installed wide band O2 sensor and readout on instrument panel. Ran two days SCCA sprints in May-no trouble. Heading to Nelson Ledges in July and I am still worried.
  5. Just curious if anyone else lost an engine at Daytona due to lean detonation? I was with Rhino Racing 1993 Mustang #288. We ran fast until lap 67 when we detonated two cylinders and trashed the engine. If anyone else experienced this, please let me know. I have questions about fuel source/octane, and ECU setup.
  6. I was reluctant to respond, but I heard those complaints in the 1960's. I thought this country had evolved.
  7. thanks for the info. I wonder if returning to the top of the surge tank is upsetting the float switch. I plan to return to the bottom of the swirl pot.
  8. Installing a surge tank in our '86 Mustang. Thinking of a float switch to warn driver (via red light) of low level. Maybe a second float switch to energize in-tank boost pump. Any ideas out there? Grumpus
  9. Back to what Bill Neace said about us Rhinos with the '86 Mustang. thanks for the compliments and the offer to become an honorary Hillbilly. I'm sorry, but my New England Yankee twang will never pass for southern Virginia hillbilly. We enjoyed talking with you, but we are still smarting from squandering that 5 lap head start on Sunday. We'll meet again. Pm me if you can spare time from fishing. Mike French
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