Underdrive Pulley
10-26-2005, 03:56 PM
#61
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Originally Posted by lt1camaro95
I bought the "race only" pulley for my LT1, that one is 50% underdriven and of course had really bad alternator issues. Even after i picked up an overdriven alt pulley, it was only 30% so i was still 20% from having my stock alt charge. Everytime i was sitting at a stop light my volts would drop to 9, i would have to keep the motor revved at the light. My wife drove my car and didnt listen to me and had the headlights on, AC on, stereo on, and sitting at a stoplight for about 2 minutes and it died in traffic. I am going to swap back to stock sized pulleys. But it was good for the track, I did drop my ET some.
wouldnt a high output alt help to solve some of this problem too...
also where do you find a pulley like that... i can't imgaine how small it was considering the size of the 25% underdrive one... it was prolly smaller than the stock alt pulley!
10-26-2005, 03:58 PM
#62
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Does seem a bit much,i was hoping to get10-12 rwhp with a slp ported tb and power bond pully.I'll never know cause i when with heads and cam also.I get it back friday,i'm pumped!!!
10-27-2005, 12:51 AM
#65
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Does anyone know if the car runs any hotter with the pulley installed? Seeing as the water pump is driven slower too.
Not that anyone would really be able to tell with the inaccurate gauges on our cars anyway, but just curious.
Thanks
-J-
Not that anyone would really be able to tell with the inaccurate gauges on our cars anyway, but just curious.
Thanks
-J-
Last edited by loloone; 10-27-2005 at 01:01 AM.
10-27-2005, 08:16 AM
#67
Originally Posted by loloone
Does anyone know if the car runs any hotter with the pulley installed? Seeing as the water pump is driven slower too.
Not that anyone would really be able to tell with the inaccurate gauges on our cars anyway, but just curious.
Thanks
-J-
Not that anyone would really be able to tell with the inaccurate gauges on our cars anyway, but just curious.
Thanks
-J-
10-27-2005, 10:04 PM
#68
Originally Posted by 777
3. Underdrive alternator pulley - gives more power by being easier to turn due to it's larger diameter. However, it is terrible for charging and shouldn't be used unless idle is upwards of 1000rpms.
Last edited by 777; 10-28-2005 at 08:26 AM.
10-28-2005, 08:25 AM
#69
Originally Posted by 98NBM_TransAm
I dont remember the stock idle for an A4, but say the idle was raised to 800rpms because of a cam etc. would the alt. pulley still be nesscary for an A4 car? (Since you mentioned that the M6 cars pump 12volts at 800rpms)
10-28-2005, 06:32 PM
#74
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former ASP pulley owner checking in....
The good:
1.The pulley seems to give an increase at low rpms as well as high. Some mods you cannot feel below 3500 rpm, or the car feels MORE sluggish. People are too hung up on peak power. There should be more mention of idle-3500rpm pwoer as well. That's the stuff you feel.
2.I got 1 mpg better on the highway on a regular basis.
3.The engine winds out a little faster, like you got lighter rockers or something.
4.Well-made part.
The bad:
1.The power steering feels heavy.
2.I wonder about long term crank balance problems , [front seal premature leak?]
3.Easier to throw a belt at high rpm? Tensioner issues? I never saw them but have heard...
4.I never noticed charging issue in my A4 2.73 car at idle, but high amp stereos may be another story.
5.Costs alot for what you get. >$200 for a tenth in the quarter!
6.Tough to install, if you don't do it right you'll kill your engine. [Tip: heat the thing for 1/2 hour in A 300 F oven, it will slip on with ease. DO NOT hammer or force it on. You need 1/8 inch clearance from the pulley back face to the fron of the crank lip.]
I'm not putting one on the current car.
Later,
Mike
The good:
1.The pulley seems to give an increase at low rpms as well as high. Some mods you cannot feel below 3500 rpm, or the car feels MORE sluggish. People are too hung up on peak power. There should be more mention of idle-3500rpm pwoer as well. That's the stuff you feel.
2.I got 1 mpg better on the highway on a regular basis.
3.The engine winds out a little faster, like you got lighter rockers or something.
4.Well-made part.
The bad:
1.The power steering feels heavy.
2.I wonder about long term crank balance problems , [front seal premature leak?]
3.Easier to throw a belt at high rpm? Tensioner issues? I never saw them but have heard...
4.I never noticed charging issue in my A4 2.73 car at idle, but high amp stereos may be another story.
5.Costs alot for what you get. >$200 for a tenth in the quarter!
6.Tough to install, if you don't do it right you'll kill your engine. [Tip: heat the thing for 1/2 hour in A 300 F oven, it will slip on with ease. DO NOT hammer or force it on. You need 1/8 inch clearance from the pulley back face to the fron of the crank lip.]
I'm not putting one on the current car.
Later,
Mike
I farted next to my car on the dyno and gained 13 hp 
