Alternators

tkr

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What kind of alternators are you guys running on your trucks and buggies? What amperage rating have you found will run all your added lights and fans etc..? We're running a rabbitt engine in our race car, and in the beginning we were running the stock alternator wound for 90 amps. With all of our lights and fans running at the night race, the voltage was dropping down to between 12 and 13 volts. I never took the time to check the actual amperage draw, but figured it was too close to our limit. So I bought a 140 amp single wire GM unit from Jegs. It worked great until the beginning of the Kartek race when it quit charging altogether. I sent it back to East Coast Auto Electric who built it, and they tell me we were spinning it too fast. I know a lot of other buggie guys are running the little Bosch units with some pretty small pullies. Do they ever have this problem? Should we switch to one of those? Any other advice?

Matt Nelson
Team Kwik Racing
 

rdc

- users no longer part of the rdc family -
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Matt,

Why not just run a pulley to spin the GM unit at the right RPM? We ran a GM in the 7S I work on and it did fine with engine RPM's up to 7500.. Heat is the only thing that killed them for us. But we had the header right under it and heat shieds solved that problem.

Tony
<A target="_blank" HREF=http://www.y-not-productions.com>www.y-not-productions.com</A>
 

tkr

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As of right now, that's the plan. I was just wondering if anyone else has had better luck with other alternators.

Matt Nelson
Team Kwik Racing
 

Kritter

Krittro Campbell
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We run a custom wound 140 amp. If interestred I can get you the contact for the winder.

Kris
<A target="_blank" HREF=http://www.dmsrace.com>www.dmsrace.com</A>
"Jesus loves you, everybody else thinks you're an A-hole"
 

tkr

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Kris -
what kind of alternator is it?

Matt Nelson
Team Kwik Racing
 

desertracer

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On our car we have been having many alternator troubles, currently we are running a powermaster that is a GM style that cranks out 80 at idle and 140 at higher rpm. We have been having trouble getting enough charging out of it. Our crank pulley is pretty small on our motor so we are not giving the alternator enough rpm for it to spin and excited to charge the batteries. Does anybody know what a proper ratio size of pulleys is supposed to be to get enough charging? I have heard that the crank pulley should be twice as large as the alternator one but not sure. I hope we can get this figured out for the night race, we are running 6 lights and all the fans so we are going to need every last bit of power.

MDR #112
 

tkr

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The guy from East Coast Auto Electric told me with sustained RPM above 5,000, you should run 1 to 1 or very close.

Matt Nelson
Team Kwik Racing
 

ntsqd

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The general rule I was given is that the alternator should spin about 6k-6.5k at the engine speed the engine is operated at the most, and that you should not exceed 10k alternator shaft speed at redline.

TS

"It only seems kinky the first time"
-- Bumpersticker seen in Lost Wages
 
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