Underdrive pulley????
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From: Las Vegas, NV
Underdrive pulley???? Who has the best and if I get one, do I need the underdrive pulley and also the alt. pulley? What will give me the most gain, but I need the alternator to get voltage to charge and A/C to work. What belts do I need? Thanks. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
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From: HTownRacing.com, TX
Re: Underdrive pulley???? just get an ASP underdrive pulley with a 10% underdrive serpentine.
there's really no need for an alternator pulley because that is simply an overdrive pulley to compensate for the fact that you now would be underdriving your pumps and electrics.
there's really no need for an alternator pulley because that is simply an overdrive pulley to compensate for the fact that you now would be underdriving your pumps and electrics.
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From: Fremont, CA
Re: Underdrive pulley???? Im running the ASP underdrive pulley with an overdrive alternator pulley. I have a decent stereo and didnt want to take the chance of not having the juice to run it. I dont have any dyno numbers, but a significant gain will be seen. The car revs much fast too, due to less rotational drag.
Re: Underdrive pulley???? I run the ASP underdrive crank and alternator pulleys and don't have a problem. It does discharge at idle but it doesn't hurt a thing as long as you don't sit too long. You can run your battery down in a heavy traffic situation. If I get into a lot of heavy traffic I put my ac on one of the lower fan settings and put my tranny in neutral periodically and bring my rpms up to charge. With a little caution the underdrive alternator pulley is not a problem. I don't understand why anybody would get an overdrive alternator pulley as you lose hp. The first time you win by a fender length you will be glad you have the underdrive alternator pulley.
Re: Underdrive pulley???? Running a overdrive alt pulley with a underdrive ASP crank pulley defeats the purpose. You might as well put overdrive pulleys on your p.s.,a.c. and water pump and end up with a net gain of NOTHING! If your electrical system draws so much current that you need to overdrive your alt then you don't really have the NEED FOR SPEED since you must be driving around in a sound system on wheels.
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From: Troy, AL
Re: Underdrive pulley???? eallanboggs, there is nothing wrong with overdriving the alt pulley. You're not giving up much. Why? Because ALMOST all of the gain from running and underdrive crank pulley comes from slowing the water pump down. That's what draws the power, NOT the alternator. The alternator also draws less power the less power is being pulled from it. Much like a generator. You ever notice a generator engine pulling down when you add load to it? So, as long as you're not running a huge electrical drain on you alternator during racing, the parasitic drag from the alternator is almost negligable. I don't car if you overdrive it 1:2...it's not going to make that much difference.
But the waterpump, on the other hand, is a TOTALLY different story. That thing can REALLY suck up some power!
For most people just getting the ASP crank pulley (it's a %25, NOT %10, btw) will work great.
The Fluid Damper is a %10 underdrive but they do make a %60 underdrive for dry sump setups. Yes, %60! Talk about chargeing problems! <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
But the waterpump, on the other hand, is a TOTALLY different story. That thing can REALLY suck up some power!
For most people just getting the ASP crank pulley (it's a %25, NOT %10, btw) will work great.
The Fluid Damper is a %10 underdrive but they do make a %60 underdrive for dry sump setups. Yes, %60! Talk about chargeing problems! <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
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From: Baton Rouge, LA
Re: Underdrive pulley???? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Colonel:
<strong>
The Fluid Damper is a %10 underdrive but they do make a %60 underdrive for dry sump setups. Yes, %60! Talk about chargeing problems! <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">GTS SS has one of those and that thing looks like a racecrank pulley for a 5.0 mustang! It's not much bigger than a coke can.
<strong>
The Fluid Damper is a %10 underdrive but they do make a %60 underdrive for dry sump setups. Yes, %60! Talk about chargeing problems! <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">GTS SS has one of those and that thing looks like a racecrank pulley for a 5.0 mustang! It's not much bigger than a coke can.
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From: Troy, AL
Re: Underdrive pulley???? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by bomax182:
<strong> Will this cause the car to get warmer faster, or raise the temps of the water in general? </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">If it does, I've never been able to tell. I ran it with my MTI 422CI engine and despite having much of the radiator covered with my FTRA kit and tranny cooler, I never had any overheating problems (not even close.) A 160 thermostat and fan settings to match are all you need.
<strong> Will this cause the car to get warmer faster, or raise the temps of the water in general? </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">If it does, I've never been able to tell. I ran it with my MTI 422CI engine and despite having much of the radiator covered with my FTRA kit and tranny cooler, I never had any overheating problems (not even close.) A 160 thermostat and fan settings to match are all you need.
Re: Underdrive pulley???? TECH Enthusiast
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From: HTownRacing.com, TX
Re: Underdrive pulley???? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif"> (it's a %25, NOT %10, btw) will work great.</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">thanks Colonel, i was thinking the % underdrive/ overdrive for the alternator.
TransAm2002 - im unsure on the exact size of the belt, however thunder racing lists it as PN# 11-760K6 for $10.99 but i know it can be done as its where mine came from any hi-lo o'reiley for im sure somewhat less. best of luck.
TransAm2002 - im unsure on the exact size of the belt, however thunder racing lists it as PN# 11-760K6 for $10.99 but i know it can be done as its where mine came from any hi-lo o'reiley for im sure somewhat less. best of luck.
Re: Underdrive pulley???? I went with the ATI dampner and it's 10 percent underdrive. I wanted to dampner the harmonics so the engine would have it's best chance to live a long time. The ATI dampner won't give a gain, but rpm should be easier on the engine, that a stock balancer or an underdrive pulley. Just my .02 worth.
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From: Troy, AL
Re: Underdrive pulley???? I think the ATI is great insurance for engines that turn super high RPMs or even those that turn sustained semi-high RPMs.
I'm have one on my C5R engine. We're hoping for 8500-9000 RPM (not tested yet.) At this level I think the ATI is an absolute must have.
I'm have one on my C5R engine. We're hoping for 8500-9000 RPM (not tested yet.) At this level I think the ATI is an absolute must have.
