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FLYIN-9
10-02-2015, 07:25 AM
Anyone running their alternator from the driveshaft?

Browndog
10-03-2015, 01:08 PM
How about no alternator? Do you really need one?

84Dave
10-03-2015, 02:47 PM
Do you really need an alternator? Yes indeed! The difference between a pure battery @ 12.5VDC & the alternator outputting 14.3V will provide about 2000 volts additional across the secondary
output of your typical race ignition coil and down to the spark plugs. You can expect slightly more
HP out of the engine with the slightly more power out of the ignition system. How much HP is required to drive the alternator? It is well known that electrically, 1 HP = 746 watts. Let's assume the alternator has the capability of a max 50-amp output @ 14 volts. Using the P=IE formula, that's .94HP @ max alternator output @ 100% efficiency. Now..... we know that an alternator and its drive system is not 100% efficient. Let's assume 80% efficiency. That would require .19HP additional to drive the system. So...... .94HP + .19HP = 1.13HP total to drive the alternator @ its 50-amp/14V max output @ 80% efficiency. The bottom line? Install a danged alternator on the front of the engine of your race car! Your performance will improve and the engine will never feel the difference driving the alternator on the race track. PLUS........... no battery charge required between practice/heat-races/Main events! -Dave-

FLYIN-9
10-05-2015, 11:38 AM
Thanks for the input. I ran for years without one, but with this new car, I'm trying to look at every advantage possible. I've been out for about 12 years & looks like a lot has changed!!

Robertms
10-09-2015, 11:07 AM
Are you still running the 2.3 fords? Robertms

FLYIN-9
10-09-2015, 11:55 AM
I still like the Pinto 2.0 engine, but not 100% sure on running it again. I'll know after the rules meeting. The 2.3's running now haven't gained but about a few tenths since I ran 12 years ago. I still think I can bump up the 2.0 though. The only problem is, we have to weigh 2400 lbs with driver. Not sure why they want them so heavy!!