alternator

[Coleydog]

If your engines only makes 140 HP you could lose 2-3 hundredths, if you're making 500 HP, not so much.
Had a El Camino 350 2 bbd, turn the AC on it would drop from 60 to 55 mph, with the 454 it never made a difference.
Another example, a grownup can pick up a 50 lb bad of feed, a 4 year can't. = HP

[Ed Wright]

Originally Posted by Coleydog

If your engines only makes 140 HP you could lose 2-3 hundredths, if you're making 500 HP, not so much.
Had a El Camino 350 2 bbd, turn the AC on it would drop from 60 to 55 mph, with the 454 it never made a difference.
Another example, a grownup can pick up a 50 lb bad of feed, a 4 year can't. = HP

And, cut it off in an EFI car, injectors open slower, leans the car. I played with that on the car I race now. Even after I tuned the WOT air/fuel ratio, I found nothing. Put two 16 volt batteries in it, picked it up a couples hundredths, no alternator & belt in the way. Starts quicker. Has to be hotter spark & starter speed.

[Bob Mulry]

Hi all,

Do you guys want to know a way that's so easy that a caveman could check an alternator for output??????

[Hacksaw]

Originally Posted by Bob Mulry

Hi all,

Do you guys want to know a way that's so easy that a caveman could check an alternator for output??????

Like maybe touching the case with steel bar screwdriver?

[Bob Mulry]

Originally Posted by Hacksaw

Like maybe touching the case with steel bar screwdriver?

I guess that you're an old guy using old guy tricks???

[Hacksaw]

Thanks. I didn't know I was old until you told me. LOL. My pops and brother were into the auto elec rebuilding business and I guess my brain retained some of their knowledge.

[cad]

I know this is an old thread, but I think tech shutting off my kill switch, while running, smoked my HOP alternator. Tech was the prior weekend. Alternator worked great for about 12 runs. Coincidentally, my race partner's ECE alternator took a crap the prior run to mine.... He teched last weekend same day as me. Both of our alternators are wired like K&R's diagram.

Any evidence of this, or ideas?

Originally Posted by Eman

On the one wire alt. if your battery is in the back how are you wiring it? I run a powermaster one wire, been on the car for almost 20 years and had to replace the regulator once. I've spoken to Powermaster,Mechman and East Coast electric and they say to run direct to battery, not the cutoff switch. They said that shutting the power off while the car was running could hurt the alternator and they don't recommend it. Called NHRA and they were very vague about having power at the alternator all of the time even with the main power switch off. I know many tracks when they tech will shut the car off from the cutoff switch as their test.
I'd say shutting off the power to a 1 wire alternator at WOT would not be recommended by the manufacturers.

[Tom Goldman]

Originally Posted by cad

I know this is an old thread, but I think tech shutting off my kill switch, while running, smoked my HOP alternator. Tech was the prior weekend. Alternator worked great for about 12 runs. Coincidentally, my race partner's ECE alternator took a crap the prior run to mine.... He teched last weekend same day as me. Both of our alternators are wired like K&R's diagram.

Any evidence of this, or ideas?

From what I've learned from 50 plus years in the auto trades ,yes the alternator manufacturers are correct ,the internal regulator can be damaged by shutting off while running.
I personally do not like having a hot lead at the alternator due to safety concerns of an internal short or other failure when the car is stored in the trailer or shop. My solution is to use a inexpensive marine battery disconnect relay between the battery and the alternator cable . the relay is controlled by the switched side of the master disconnect. I have not experenced alternator failures since using the relay and have had the power shut off tested at several National events. costs around $35 on Amazon

[CMcAllister]

Battery disconnect solenoid controlled by a switch in the drivers reach in Stock.

Legal or not? I've been told no. Rule book says it has to be "functioning".

[Eman]

When my alternator went bad, possibly from shutting off the power while running, it caused the alternator to draw the battery down. The alternator was still charging while running but would kill the battery while sitting.