Differences in these three underdrive pullies?
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I'm looking at the 3 different pullies on www.ls1speed.com and the various forms they come in.
First the no-name:
"SFI Approved Underdrive Pulley"
This pulley comes in both 10% and 25% underdrive forms.
The next pulley is the:
"March Fluid Dampened Perfomance Pulley" which is only offered in one configuration.
Finally there's the:
"Auto Specialties Underdrive Pulley"(ASP) sold in two configurations.
Crank & Alternator pulley set or 25% Reduction Crank pulley.
Now the first no-name pulley looks like a pure race engine pulley since it has no built in dampener?
The March pulley has a dampener but they don't say what the reduction is on the pulley.
The ASP pulley has a dampener but what's the difference between the Crank & Alternator pulley set as compared to just the 25% reduction crank pulley? I don't see why their are two different setups unless one is more underdriven or better than the other?
First the no-name:
"SFI Approved Underdrive Pulley"
This pulley comes in both 10% and 25% underdrive forms.
The next pulley is the:
"March Fluid Dampened Perfomance Pulley" which is only offered in one configuration.
Finally there's the:
"Auto Specialties Underdrive Pulley"(ASP) sold in two configurations.
Crank & Alternator pulley set or 25% Reduction Crank pulley.
Now the first no-name pulley looks like a pure race engine pulley since it has no built in dampener?
The March pulley has a dampener but they don't say what the reduction is on the pulley.
The ASP pulley has a dampener but what's the difference between the Crank & Alternator pulley set as compared to just the 25% reduction crank pulley? I don't see why their are two different setups unless one is more underdriven or better than the other?
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I have the ASP crank and alternator underdrive set. The crank pulley slows all of your accessories down 25%. The the alternator pulley gives an additional 23% more reduction in rpm to only the alternator.
I have an A4 tranny. Full charge is about 900 rpm. It does discharge at idle but is not a problem as long as I don't sit with the ac on for a prolonged period of time.
For maximum hp gains get both pulleys. With your M6 should not be a problem with charging. If you do a lot of city start and stop driving and have an A4 then get just the crank.
ASP does make an overdrive alternator pulley (smaller than stock) to speed the alternator to almost stock speed. You would have to request overdrive alternator pulley for this set.
I have an A4 tranny. Full charge is about 900 rpm. It does discharge at idle but is not a problem as long as I don't sit with the ac on for a prolonged period of time.
For maximum hp gains get both pulleys. With your M6 should not be a problem with charging. If you do a lot of city start and stop driving and have an A4 then get just the crank.
ASP does make an overdrive alternator pulley (smaller than stock) to speed the alternator to almost stock speed. You would have to request overdrive alternator pulley for this set.
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All of the pulleys work as a dampener. THe noname one is setup kinda like the stock configuration but none the less it operates as a dampener as well. The march should also be 25% reduction