I am looking to buy some underdrive pulleys for my 305 TBI. All the ones I have found are only for the TPI and 305/350 Truck. I know heads and exhaust amnifolds are swappable. So would the pulleys be also.
http://www.jegs.com/cgi-bin/ncommerc...16&prmenbr=361 Which one of these would I get.
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if you wanted those you should get 88-92 TPI pulleys
Well does anyone have a suggestiong of what I should get?
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www.aspracing.com
the crank pulley is the only one that is going to net you any power. Type the ASP part number into summitracing.com, i believe they sell them for cheaper
the crank pulley is the only one that is going to net you any power. Type the ASP part number into summitracing.com, i believe they sell them for cheaper
Senior Member
i just went with the March two piece 88-92 pulley kit for my LO3.i picked up an honest tenth in the quarter mile.Only thing i dont like about them is the battery doesnt charge until 1500 rpm because it slows all your belt driven junk down
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Quote:
Originally posted by Dennis91RS
i just went with the March two piece 88-92 pulley kit for my LO3.i picked up an honest tenth in the quarter mile.Only thing i dont like about them is the battery doesnt charge until 1500 rpm because it slows all your belt driven junk down
You installed both the underdrive crank and the underdrive alternator pulley?Originally posted by Dennis91RS
i just went with the March two piece 88-92 pulley kit for my LO3.i picked up an honest tenth in the quarter mile.Only thing i dont like about them is the battery doesnt charge until 1500 rpm because it slows all your belt driven junk down
Senior Member
yep the crank pulley is smaller than the water pump and the alternator pulley is just a tick maybe like a couple mm bigger than the stock one
Supreme Member
I'de suggest putting the stock alternator pulley back on to get the charging back at low rpms if you are concerned with that.
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yeah, use the stock alternator pulley. First i installed my crank pulley and had no charging problems so i said, "what the hell, might as well install the alternator pulley", killed the alternator in about 4 months.
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So you get an altenator with a lifetime warrenty and let it die every 4 months 

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90RS305
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Quote:
Originally posted by PyRo9862
So you get an altenator with a lifetime warrenty and let it die every 4 months
Originally posted by PyRo9862
So you get an altenator with a lifetime warrenty and let it die every 4 months

Supreme Member
My dad had pulleys on his Bronco for like, 2 years without a problem. Its how you drive the car. We drove it 90% highway. If you do alot of idling, then you might have a problem.
March does make a set that increases charging capacity.
March does make a set that increases charging capacity.
Here is a set will these suffice. Pulley set 88-92 camaro/Firebird 25% crank/23% alt full @950 rpm They are ASP-540801 on summitracing.com
Senior Member
im not worried about it cause i only drive the car to the local dragstrip and once in a while cruise in