lt1 underdrive crank pulley w/o the different alternator pulley?
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can u just use the crank underdrive pulley and stock alternator pulley? will it make any difference?
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if u use the stock alt pully with a smaller underdrive pully, ur alternator will be charching much less, ur voltage gauge will drop down and the battery will die very soon
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Maybe with a stock engine but his mod list looks to include heads and cam which would result in a raised idle, eliminating any charging issues.
UD pullies are not particularly worthwhile, you get like .1 from pulling the belt, if the pullies are 34%ud it stands to reason maximum gain is .034.
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I ran the crank pulley w/o the alternator pulley for about 15k miles. Then one night, I was at the track, in line for my next race. Some dodo brain dropped his tranny in the middle of the track. By the time they had cleaned the track off, my battery had discharged (I was sitting there idling). I put the alternator pulley on and have not had a single problem since then. And the voltage on our inaccurate in-dash gauge is higher now as well (duh).
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I ran the crank pulley w/o the alternator pulley for about 15k miles. Then one night, I was at the track, in line for my next race. Some dodo brain dropped his tranny in the middle of the track. By the time they had cleaned the track off, my battery had discharged (I was sitting there idling). I put the alternator pulley on and have not had a single problem since then. And the voltage on our inaccurate in-dash gauge is higher now as well (duh).
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I purchased ASP 847600 underdrive pulley for the crank, ASP 520004 overdrive pulley for the alternator, and a Gates belt.
Just remember, if you change the pulley now, you will have to change your belt as well because the alternator underdrive pulley is smaller in diameter than your stock pulley.
Just remember, if you change the pulley now, you will have to change your belt as well because the alternator underdrive pulley is smaller in diameter than your stock pulley.
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I put the asp pulley on the crank only and have had no problems with anything charging wise for 30,000 miles. LT1 altenators are 140 amps that's pretty beefy. do a big 3 upgrade first if you are that worried
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I never have put on the alternator pulley and ran 80k in a 6 speed and over 100k in an auto. It can be done and I have never had a problem with the batteries giving out early. If you are worried about it spinning too slow at idle, have the idle bumped up a few 100 rpm.
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A non-********, serious, response by me to the OP: If you do a lot of stop-and-go driving, or have a sound system (I'd say even the Monsoon 10spk might be enough) then I'd get the Alt pulley as well, just to play it safe.
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