is it worth getting the UR pulley for an AT TL. what is the different between the OEM and the UR one that make it gain the power.

 

biggest difference is weight reduction - You may have some better answers if you do a search in the Performance Parts & Mods section for "unorthodox under drive pulley"

 

the pulley is just like a lightweight flywheel. no real hp gain. just less rotating mass to turn. which lets the engine turn faster.so you build power faster.

 

I checked out with unorthodox and they do not have one for the 3rd gen TL.

 

Then whats this?

 

Mods, can we get a section in the 3g garage on pulleys?


https://acurazine.com/forums/showpos...6&postcount=14

 

lembowski...

a little harsh but

 

Not harsh.............I would have linked him to it, but there was no direct link on the site as you can see.

 

UR does offer an underdrive pulley and a stock size pulley. You will notice that hte car revs out quicker. It usually is good for a 7-8 hp gain.

 

true - true

 

I have the stock sized UR Pulley and I love it. The weight difference is nuts and you feel it in the car too. Gains are the best for the $$$ Talk to Excelerate he will help you out

 

Enough said! Thanks!!!

 

I'm looking to get this mod soon,
But I have a question.

What is the difference between the "STOCK DIAM." Ultra Sc & the "UNDERDRIVE" Ultra S?

Which one will get me more power or allow the car to go faster because of the weight loss?

Thanks guys

 

The "Stock Diam" is the same size as the stock pulley. Where as, the "Underdrive" underdrives the accessories slightly by being smaller in diameter....

Both are a reduction in weight; the Ultra S will give you a slight increase in power versus the stock-sized one since it's smaller. This is granted you don't have a sound system req. more than 600 watt RMS or a supercharger. In those cases, an underdrive pulley will produce adverse effects.

 

I you are not buying a system get the underdrive if you have a big system get the stock ur pulley either way you will gain horsepower

 

In regards to the UR pulley I have these questions if anyone can help:

1. Does a stock sized UR pulley have the weight reduction to make a difference, and if so about how much HP is the difference?

2. What is the down side of going with another size pulley? Do potential problems extend to fully loaded vehicles even without a SC or 600w stereo as stated above?

3. Would a larger alternator correct this?

Please help me understand. I'm interested in the part but I want to be sure it's situationally appropriate for my car.

 

1. Yes, there is a huge difference in weight. The stock one is steal with a rubber insert, while the UR one is billet Aluminum. Much lighter( stock dia. or underdrive)

2. When sitting at a light your air will not be as strong, your alternator will not charge at 14 volts but rather 12.5-13, and power steering will be slugish at idle.

3. NO, as its not the equipment, its the pully diameters. The speed of the pulleys turning has changed.

 

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Right...
The underdrive pulley is smaller in diamtetr (slightly), thus it turns your accessories slightly slower. MOST of your power is gained from the reduction is weight (stock or undersriven), and the underdriveing accounts for the equivalent of 1HP (15% of your HP gain comes from underdriving according to UR).

2) Negatives? Turning your AC compressor slightly slower will cause it to be slightly less effecient (won;t cool as well), which may be noticeable at idle.
The power steering pump being turned slightly less may cause slight "binding" at idle, where the steering binds for a second (as the pressure build up again) while turning. Given the lack of steering sensitivity on the TL, I don't think this will ever be a problem.

I've only READ about these potential issues, and have never read anyone here complain about them. Some think there might be engine bearing risks with running these, but most are of the opinion that thisis not an issue.

3) You don't need any additional equipement to run the pulley. These issues described are testbook, and given the number of folks using them, I don't think you'll ever notice.

There may be an upside in that the undersriving of the accessories may actually preserve them a few extar thousand miles. Less cycles = less wear... again, another theory.

 

Is that for the smaller diameter pulley or the stock sized one thats just lighter?

 

They're both way lighter guys.
Do some searching and homework on these. This concept is not new, and this has been discussed many time before.

Smaller diameter pulley = underdriven... Hence the AC compressor is being "under-driven", not using full power to crank the AC but reusing that power to "go".

 

I think the underdrive crank pulley for the 3rd gen TL is 14 oz and the stock size is 16 oz. The gains will be very similar between the 2 pulleys.

 

Only for the under drive pulley. The stock size is still turning all the other pulleys at the stock speed. The weight difference just means there is not as much of a load on the motor. It will actually idle better (in theory).

 

So in theory if there is not as much load on the motor, when you do get on it its going to have less weight so it'll spin faster, so you'll build power faster right?

 

Correct, less rotating mass, therefore the power being produced by the engine is used to propel the car forward, rather then turn the heavier crank pulley. This is the same principle with a lightweight flywheel.

 

could I get a quick part number?