Quote:
Originally Posted by Formula413
So I was at the dragstrip the other day (how many threads on Ecomodder start like that?) and while waiting in line to make a run I would shut the engine off, wait until the cars ahead of me had moved up several spaces, start it back up and move forward, etc etc, to help keep the engine cool. A friend of mine suggested that this was ultimately counter productive because the alternator would have to do extra work to replace the charge lost by cranking the starter.........There would also clearly be a large difference between the energy needed to start the 2 litre four cylinder engine in my Escort vs the 5.7 litre V8 with 10.4/1 compression in my Firebird. Would an amperage gauge possibly be useful in determining this? Let hear some theories.
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Hey, I'm the guy that made money last weekend drag racing my 3 cylinder bone stock Geo. Lots of racers do what you do or simply get out and push, not to save gas, but to keep their motors cool. From what I have garnered from these economy forums cars like my Geo use as much gas to restart as 10 seconds of being at idle while a V8 might take over 30 seconds worth. Heat soak would not be much of a problem since every restart will circulate coolant that was in the rad in place of that in the hotter motor. I like many racers have a aswitch to turn on the fan even with the engine off. If you are bracket racing and want the car to be consistant you should keep it at your normal highway coolant temp and keep it running a couple of minutes or more before you hit the starting line. On computer controlled cars sometimes this helps out a lot.....then to keep it cool I turn on my defroster that automatically runs the fan....or turn on the AC....BUT....if you run the AC make sure you turn it off way before you get to the ready line since you'll be dripping condesation and not be allowed to rum since you are dripping liquids onto the track. I also turn my fan on every time that I am getting ready to stage, even though if not needed it will cause alternator charging drag and slow the car down, byt because it might come on during the run....remember that consistancy is the name of the game. My Horizon used to slow down nearly .2 seconds with the fan on, and it would slow down also about that much if the time trials were in the day but the racing was at night....I took months to figure this out, while all my V8 oppoments were going faster at night with cooler air I was going slower! I also tried an alternater kill switch to simply race on the battery and have no alt drag....the computer in the Horizon did not like the 12 v from the battery and the car ran like crap. On my 98 Neon the car loved running with the alt shut off. I guess it all boils down to the individual car.