Auto X-prize competitor: 80MPG '87 Mustang WITH MUSCLE on E85

tuna55 wrote: There's no free lunch - an electric water pump takes the same amount of power to run as a mechanical water pump. Normally far more because of losses. Power is power, whether measured in watts or hp. Volts * amps = watts period. You can't change that.

True, but in most instances, the mechanical water pump RPM is tied to engine RPM where as the electric water pump arrangements I have seen are set up to run at a constant RPM. When I was in college a guy I knew was working on a research project converting a Ford 4.6L engine to use an electrical thermostat and electric water pump. IIRC he documented a 5% increase in MPG by operating the engine a more steady temperature over all operating conditions and with the lower speed, constant RPM electric water pump.

Constant temperatures are easily achieved by a thermostat. Perhasps the pump itself was more efficient than the OEM version, but that's about all the gain you'd see, because the power spinning the electric pump will increase with RPM too, perhaps not by as much.

I think the premise was to achieve more stable temperatures with the electronic thermostat and the electric water pump turned at a constant RPM regardless of engine RPM. At lower engine speads there probably wasn't much of a difference, but at higher engine speeds, when the mechanical water pump was still turning at some function of engine RPM and losing efficiency, the electric was still turning at the low RPM. Part of the research was to show that the engine would cool more efficiently at a lower pump speed. Unfortunately, that isn't an option with a mechanically driven unit b/c the engine would overheat at idle from the pump being driven too slowly.

I think the guy's full of crap as well. E85 typically has around, IIRC, 80% of the energy of gasoline meaning right there you have a 20% jump in fuel consumption. So if the Mustang got 24 MPG on gas, doing the same thing on E85 would now mean 19.2 MPG. This is real; my customers with flex fuel cars complain about that all the time. So he's starting out with a 20% ass whoopin' even before he works his electronic magic. Of course, by now the oil companies have paid him off just like they paid off the guy with the 300 MPG carburetor.

The problem with electric anythings on a car: the battery has to be big enough to store power for all the different items to work and that battery must be constantly recharged. That means the alternator has to be capable of enough amp output to run all the electrical accessories yet still have enough over capacity to recharge the battery and an alternator that big will still need quite a bit of power to operate. This can easily be seen by running a gas generator and then using it to operate a high amp draw device, the engine slows down and the throttle then opens to bring the gennie back to the desired RPM.

So you can cut parasitic draw by removing, say, the water pump drive from the drive belt system but you add back the power drawn by the alternator and now your parasitic draw savings is not so great.

Some of the drag race guys run everything (water pump, fuel pump, steering pump, etc) from electric motors to cut drag and do this successfully. The difference: they operate on a 'total loss' system meaning no alternator to draw engine power, the battery must be recharged after every run in order to keep all the electrics operating in the correct voltage range. That's one reason a lot of them run 16V batteries and they can get away with it since typically the time they are running the engine is measured in minutes.

Did anyone watch the Mythbusters episode that tried to bust / prove some of the high MPG myths? The 300 mpg carb was one. (Why didn't they test the tornado!?!?!?)

Many drag racers actually run alternators, including my pops on his old super pro cars (high nines) and super stock cars (low nines) even with two 12V batteries, because the ignition takes away too much power without the extra amperage to make the belt savings worthwhile. This is even charging the battery after every run.

To show how times have changed, we used to build 'total loss' battery powered ignition systems for the old 6V points and condenser Honda dirt bikes. That way you could remove the flywheel and magnets for the ignition and the motor would then rev like a 2 stroke. Most of us ran them off of lantern batteries and they would go all day on one of those. The real hardcore weight loss guys would run C batteries and they'd be good for one 20 minute moto.