Underdrive Pulley-need your opinion!
01-27-2003, 01:45 PM
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Underdrive Pulley-need your opinion!
Hey all-
I've been communicating with a gentleman at Unorthodox Racing about having an underdrive pulley made for the 3.4L engine. Here's the scoop:
For those of you that don't know what an underdrive pulley is, it is a lighter pulley that replaces the stock crank pulley. Generally, the aftermarket pulley is smaller and, therefore, turns accessories slower. The fact that it is lighter means that it takes less power to turn. Typically, you can expect to see 3-10 hp gains depending on existing modifications.
Here's the catch:
There would have to be two different pulleys made-one for supercharged engines and one for N/A engines.
Unorthodox said they would need a stock pulley to take measurements. I don't think that's a problem. I can get one from a local junkyard so that noone has to endure any down time.
I'll also be inquiring about one for the 2.7L and the 3.0L so that no one feels left out.
So, with that said, would anyone be interested if I got a group buy together?
Does anyone have any other questions/comments/remarks/concerns?
I've been communicating with a gentleman at Unorthodox Racing about having an underdrive pulley made for the 3.4L engine. Here's the scoop:
For those of you that don't know what an underdrive pulley is, it is a lighter pulley that replaces the stock crank pulley. Generally, the aftermarket pulley is smaller and, therefore, turns accessories slower. The fact that it is lighter means that it takes less power to turn. Typically, you can expect to see 3-10 hp gains depending on existing modifications.
Here's the catch:
There would have to be two different pulleys made-one for supercharged engines and one for N/A engines.
Unorthodox said they would need a stock pulley to take measurements. I don't think that's a problem. I can get one from a local junkyard so that noone has to endure any down time.
I'll also be inquiring about one for the 2.7L and the 3.0L so that no one feels left out.
So, with that said, would anyone be interested if I got a group buy together?
Does anyone have any other questions/comments/remarks/concerns?
Last edited by HaveBlue; 01-27-2003 at 02:15 PM.
01-27-2003, 02:19 PM
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I would definetly be interested in the N/A version. Do you know if the stock pulley adjustments would be sufficient for belt tension with the new crank pulley?
Or would we have to "find" belts that would fit the new, smaller pulley?
Sounds great. Keep us posted!
Or would we have to "find" belts that would fit the new, smaller pulley?
Sounds great. Keep us posted!
01-27-2003, 06:27 PM
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Having a 3.0 and seeing what happens to my lights when the RPMs drop below 800 they dim quite a bit. Isn't that hard on the bulbs? Not to mention that having it turn the accesories slower will have the same effect on my truck.
01-27-2003, 06:52 PM
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Back in the day when I used to be into Mustangs, underdrive pulley kits were one of the first mods that we would do. It was also one of the only bolt-on mods that you ever "felt" the difference. My past experience is that this is a very benificial, and very economical mod. It should work very well on N/A trucks.
That being said...
I can't see a benifit of doing this with a supercharged truck. An undrive crank pulley causes all of the accessories (like the alternator, powersteering pump, A/C compressor...) to turn slower. Each of these accessories requires a certain amount of horsepower to opperate. If you turn them slower, you redirect horsepower from the accessories to the rear wheels. This would be great in a N/A truck. But in a supercharged one you would be truning the supercharger slower, thus lowering boost.
You could make it work with a suprecharger but it would require a two pulley system. One crank pulley to slow everything down, and one supercharger pulley to speed up the blower. Someone would have to figure out the formula to get the speeds just right.
I have had underdrive pulleys on a few different cars with no problems. A couple of them had some pretty big audio systems in them and the draw was never too much to the "slower" alternator. I suppose you could encounter problems but you would have to put one heck of a load on the accessories.
That being said...
I can't see a benifit of doing this with a supercharged truck. An undrive crank pulley causes all of the accessories (like the alternator, powersteering pump, A/C compressor...) to turn slower. Each of these accessories requires a certain amount of horsepower to opperate. If you turn them slower, you redirect horsepower from the accessories to the rear wheels. This would be great in a N/A truck. But in a supercharged one you would be truning the supercharger slower, thus lowering boost.
You could make it work with a suprecharger but it would require a two pulley system. One crank pulley to slow everything down, and one supercharger pulley to speed up the blower. Someone would have to figure out the formula to get the speeds just right.
Is there anything bad about this?
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01-28-2003, 06:45 AM
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That was an issue that was mentioned by the rep from Unorthodox. He said that a pulley could be made to the stock specs but it would be lighter. So, essentially, there would probably be two pulleys available for the 3.4L, a smaller one for N/A engines and a "normal" size for S/C'd engines.
I have yet to hear about pricing. I will let all of you know when I do.
I have yet to hear about pricing. I will let all of you know when I do.
01-28-2003, 07:46 AM
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Hey all, I'm new here and figured I'd chime in and see if I could offer some advice on the pulley.
I currently own a N/A Dodge Stealth and one of the big mods for this car is an underdrive pulley, the most popular of which is made by Unorthodox Racing. The people I've talked to who have them on their cars say they make a big difference in power and are well worth the money (about $150 - $180). But, one main issue that always comes up is that the pulley doesn't have a harmonic balancer. Not sure if this will be true about the pulley for the Toyota 3.4? Some people will argue that not having a balancer will cause more stress on the engine's internals and shorten its life expectancy.
Just something you may want to consider!
-Scott
I currently own a N/A Dodge Stealth and one of the big mods for this car is an underdrive pulley, the most popular of which is made by Unorthodox Racing. The people I've talked to who have them on their cars say they make a big difference in power and are well worth the money (about $150 - $180). But, one main issue that always comes up is that the pulley doesn't have a harmonic balancer. Not sure if this will be true about the pulley for the Toyota 3.4? Some people will argue that not having a balancer will cause more stress on the engine's internals and shorten its life expectancy.
Just something you may want to consider!
-Scott
01-28-2003, 08:14 PM
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This thread kind of makes me sorry that I didn't mention underdrive pulleys sooner. I didn't realize that the Toyota crowd hadn't heard of the benifit. We need to find someone that makes them so that all you guys can experience the low buck, high yeild results that underdrive pulleys have to offer.
01-29-2003, 06:37 AM
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Update-
I just wanted to let everyone know that I sent a reply e-mail to Unorthodox about several of the questions posted here including belt squeel problems, belt size issues, alternator output, harmonic balancer issue, and pricing. I'm going to see if I can work out a group purchase so that we can all take advantage of the benefits at a reasonable price.
Also, I was thinking, since a lighter pulley takes less effort to turn, wouldn't better economy be an added benefit? Have any of you who have used UDPs in the past experienced better mileage?
In either case, if they do develop one for us, I will be the first to try it and monitor any performance improvements and mileage differences.
Also, I was thinking, since a lighter pulley takes less effort to turn, wouldn't better economy be an added benefit? Have any of you who have used UDPs in the past experienced better mileage?
In either case, if they do develop one for us, I will be the first to try it and monitor any performance improvements and mileage differences.
01-29-2003, 07:48 AM
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When I was into the Mustangs it wasn't really economy that we were monitoring. I couldn't say for sure that there was any mileage gain. Just to give you an idea, the last Mustang I owned was a '93 LX that put about 500hp to the rear wheels. At the track it would keep the front wheels off the ground for about the first 50 feet and turn 11 sec. 1/4 mile runs. Economy was not a priority.
01-29-2003, 08:16 AM
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Originally posted by tomus1000
When I was into the Mustangs it wasn't really economy that we were monitoring. I couldn't say for sure that there was any mileage gain. Just to give you an idea, the last Mustang I owned was a '93 LX that put about 500hp to the rear wheels. At the track it would keep the front wheels off the ground for about the first 50 feet and turn 11 sec. 1/4 mile runs. Economy was not a priority.
When I was into the Mustangs it wasn't really economy that we were monitoring. I couldn't say for sure that there was any mileage gain. Just to give you an idea, the last Mustang I owned was a '93 LX that put about 500hp to the rear wheels. At the track it would keep the front wheels off the ground for about the first 50 feet and turn 11 sec. 1/4 mile runs. Economy was not a priority.
So what does a 500hp get in mpg? 2? Maybe 4?
01-29-2003, 08:23 AM
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At full throttle? Less than that. I guess that it would burn a little more than 1 gallon of 107 octane in a 1/4 mile run. At 5 dollars a gallon, it was not the car that you wanted to drive back and forth to work everyday. it was pretty thirsty. 
02-09-2003, 07:12 PM
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Alan,
I'm interested! Does this provide more low end torque? I'm sorry if someone already said this above, but I didn't have time to read it all.
Thanks,
Chris
P.S. How's the write-up for the fuel atomizer and heat exchanger coming along, Alan?
I'm interested! Does this provide more low end torque? I'm sorry if someone already said this above, but I didn't have time to read it all.
Thanks,
Chris
P.S. How's the write-up for the fuel atomizer and heat exchanger coming along, Alan?
02-09-2003, 07:30 PM
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I believe it will provide more low-end torque. I think it will provide more "grunt" over the entire RPM band. Someone correct me if I'm wrong.
I need to call Unorthodox and speak to the guy I've been e-mailing to work out the details with pricing, etc.
As for the write-up, I still need to get one done. I haven't had too much time unfortunately. I promise, I'll get one done soon for ya!
I need to call Unorthodox and speak to the guy I've been e-mailing to work out the details with pricing, etc.
As for the write-up, I still need to get one done. I haven't had too much time unfortunately. I promise, I'll get one done soon for ya!
