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Discussion Starter · #1 ·
i know underdrives have been talked about 1000 times but i havent found the info im looking for.

my 87 GN is going to be a 90% strip car- but still drive on the street to car shows and events. i have manual steering, and an electric water pump- no AC. so all thats left is the alternator, and crank pulley

if i do the 200 amp alternator upgrade can i get away with a stock sized RJC alternator pulley and a RJC underdrive crank pulley?

i dont want my charging system to be suffering going down the track making everything else suffer. the car doesnt have a stero anymore but does have a big external fuel pump, electric water pump, dual fans, fast xfi, and some other big loads.

thanks :D
 

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Someone Crown My Ass!
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Just bypass the A/C. I had one on my old GN (Racing) and the gain was so little it wasn't worth it. Having power in these cars makes more sense.
 

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Discussion Starter · #3 ·
i dont have AC- champion delete bracket- all it is is an alternator and crank pulley
 

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My street car has a 50% underdrive crank pulley and a smaller pulley on the alt. to pick the rpm's back up for charging; made a difference at the track (>1/10), the 24% underdrive did nothing but discharge at a traffic light. Check pic. of alt. in my thread to see alt. pulley. I have had no problems with this setup for years on the street and no one makes anything less than 50% on the crank I believe. BG sold this two piece setup years ago and I think someone still sales this today. :usa:
 

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Discussion Starter · #5 ·
thanks william

i think to make the champion bracket work im going to need the smallest pulleys i can get or else it hits the electric waterpump- i beleive thats what banning did.
 
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