Ford vs Chevy Build-up

[jcw31]

Rich a one wire alt. has to turn around 2000 rpm to excite it for it to start charging. Once it starts charging it stays until you shut off the engine


Joe

[HandOverFist]

Originally Posted by jcw31

Rich a one wire alt. has to turn around 2000 rpm to excite it for it to start charging. Once it starts charging it stays until you shut off the engine


Joe

This one excites at 880rpm...when its working. http://www.jegs.com/i/JEGS-Performan...oductId=752892

[Sean Marconette]

Bob is right on. That crank pulley has to be close to 3.5", if the alt pulley is 2", that calculates to 12,250 at 7000 RPM. At 1000 RPM the alt is only at 1750 RPM.
Will the alt produce any voltage if you increase the engine RPM to 2000 or 3000?

Sean

[HandOverFist]

Originally Posted by Sean Marconette

Bob is right on. That crank pulley has to be close to 3.5", if the alt pulley is 2", that calculates to 12,250 at 7000 RPM. At 1000 RPM the alt is only at 1750 RPM.
Will the alt produce any voltage if you increase the engine RPM to 2000 or 3000?

Sean

From the beginning both alternators worked fine, even at idle. I guess they lasted part of one stint each at the track when I realized they were no longer charging. You can wing it to six grand if you like...it aint happening. Something inside the alternator is just not holding up it's end of the bargain.

[Alan Nyhus]

Just went through a similar issue. The one wire alternator didn't excite until 2500 alternator rpm. With the combination of a large alternator pulley and small crank pulley, there wasn't a lot of time that the alternator was putting anything back into the battery. To make things worse, the alternator had a bad diode and rectifier so it was only putting out 15 amps when it was charging. Had it rebuilt and now it works fine.

Changed the charging system to a larger 74 amp constant output alternator with a 6" crank pulley. The excite power wire runs through a heavy duty toggle switch on the dash so the alternator can be turned off during a run. -Al

[Tony Corley]

As long as he has a good alternator, his pulley sizes are fine. I have ran the same pulley set up on 7 different cars with no issues, although I have always used Powermaster 1 wire alternators.

[HandOverFist]

I'm going to try this one guys... http://www.summitracing.com/parts/tff-70686g

Listed for '85 models, but I don't see any difference in the case. Funny how the old one on the Camaro has never had an issue. What's the cheapest alternative in a Powermaster Tony?