NST (NonStopTuning) Pulleys. Info, Specs, User Data...

[YarisGuy]

A lot of these questions where brought up in the original GB thread when we all signed up for these pulleys. The vibration damper in the stock pulley is a think rubber band that hardly does much. After talking with Mike of NST on his screen name (NSTonAIM) it sounds like NST is capable of building pulleys with these rubber pieces in them, but the costs would be 3 times what they are now. The rubber is very over rated and NST has removed it in 99% of the cars they build pulleys for. The rubber has not proven to be a necessary component of the pulley in all their testing and the testimonial of thousands of aftermarket pulley users for the past 15 years or so.

.

[tk-421]

Originally Posted by largeorangefont

Adding a vibration dampner to the NST would probably double its price...

Originally Posted by YarisGuy

NST is capable of building pulleys with these rubber pieces in them, but the costs would be 3 times what they are now.

I don't mind having a bit more vibration in the car, especially with the obvious advantages that a crank pulley brings to the table. I guess I just don't understand why a rubber band would increase prices so dramatically.

[eTiMaGo]

Originally Posted by tk-421

I don't mind having a bit more vibration in the car, especially with the obvious advantages that a crank pulley brings to the table. I guess I just don't understand why a rubber band would increase prices so dramatically.

Well, I would guess a pulley is being made in a two step process (CNC mill, then anodize), but if you want a rubber insert, it would be made in a lot more steps, as two pieces of aluminium need to be made, then a piece of rubber needs to be made, and sandwiched between the aluminium. All these extra steps would need more time, and a lot more labor, and as a result, a lot more money

[tk-421]

Originally Posted by eTiMaGo

Well, I would guess a pulley is being made in a two step process (CNC mill, then anodize), but if you want a rubber insert, it would be made in a lot more steps, as two pieces of aluminium need to be made, then a piece of rubber needs to be made, and sandwiched between the aluminium. All these extra steps would need more time, and a lot more labor, and as a result, a lot more money

Thanks for the explanation. I just thought it was a rubber ring we were talking about here. Seems to be more like an aluminum hoagie now.

Great. Now I've got the munchies.

[NonStopTuning]

Originally Posted by eTiMaGo

Well, I would guess a pulley is being made in a two step process (CNC mill, then anodize), but if you want a rubber insert, it would be made in a lot more steps, as two pieces of aluminium need to be made, then a piece of rubber needs to be made, and sandwiched between the aluminium. All these extra steps would need more time, and a lot more labor, and as a result, a lot more money

Thanks eTiMaGo, you pretty much nailed that one on the head.

Furthermore on the topic of the rubber damper, engine vibrations, or possible threats resulting from elimination of this rubber piece...

On a relatively understressed near stock motor with bolt ons or low amounts of boost like what most of the people on this forum probably run, a solid pulley will not have any life threatening consiquences. The factory pulley with a 2mm (less than a 1/8th inch) damper is primarily there for wide band NVH (noise vibration harshness) supression from the engine and driveline. Removing the damper and replacing it with a solid pulley will lead to minor addtional NVH but will not harm the engine. In fact, most people claim their engines seem to run smoother with NST pulleys.

The engineering reasons are that most modern engines have a short, strong crank with, a relatively high natural frequency. The dangerous second harmonic that can cause damage occurs at an rpm that this sort of engine will never see, in the area above 10,000 rpm. Even the stock damper is not tuned for attinuation at this sort of rpm so the argument is somewhat of a moot point.

Now small engines that are pushing the limit with lots of revs, wimpy cranks, super long strokes, lots of boost and dwelling in the upper rpm ranges for long periods of time can benefit from a damper designed to deal with this sort of operation but our engine is not like this, and probably very few people with this motor on this forum push the envelope that hard. How many 1.5Liter, 400HP, 11,000RPM Yaris motors do we have on these forums?

As far as I can tell, our engine has a strong and stiff bottom end that is well built for our intended use. It has an internaly balanced crankshaft which is less like to break due to torsional vibration.

There are a lot of Nissan guys who use underdrive crank pulleys in road racing series like NASA or SCCA. Road racing is much more punishing on an engine than other motorsports. The engine is subjected to run times lasting 23 to 45 minutes with the engine always in the upper ranges of its rpm limit. One race weekend is the equivlent of hundreds of 1/4 mile passes.

NST sponsors the first ever wheel to wheel Scion tC NASA Road Race car. This car has been using underdrive pulleys from NST with great results since day one.

NST also sponsors two drift cars participating in the professional US drift series, Fromula Drift. Both of these cars have been using NST pulleys with no issues of any kind for the past few seasons.

We could go on and on...

Is a solid crank pulley harmless to all engines? No it is not. Small, super high reving engines, when modified way past the simple bolt on stages may have problems. These engines reach critcal harmonics, past the 10,000 rpm range, an rpm often reached by certain race engines.

A mildly modded inline six will most likely be fine but one subjected to high rpm for long periods of time (90% of its life) with lots of boost will probably suffer. In this case , the stock balancer/damper is probably not adequate either.

Some of the older american V8 engines are externaly balanced and it is critical not to use a solid hub pulley not designed for these applications, or damage to the engine could result.

Our engines and most around here do not fall into the above catagories. Rest assured that your engines will not blow up and die or have a reduced life in street and even racing use with these parts.

I would bet that every "expert" that tells you otherwise has little personal, practical, real world experience with the subject.

.

[kurokoma-kun]

Installed mine last weekend, got a little over 200 miles on it now. Like others have said, faster, smoother acceleration, a good bit more bite in the bottom of 2nd gear, also much smaller "hole" in the top of 2nd/3rd. GREAT $100 mod--looking forward to NST releasing the rest of the set.

About the torque thing though--earlier post said less rotating mass means less torque, but it feels like more... How does less force to get the thing spinning affect torque? Or am I just confused about how torque works? Only explanations I can find online have too many mathematical equations...

[NonStopTuning]

Originally Posted by kurokoma-kun

Installed mine last weekend, got a little over 200 miles on it now. Like others have said, faster, smoother acceleration, a good bit more bite in the bottom of 2nd gear, also much smaller "hole" in the top of 2nd/3rd. GREAT $100 mod--looking forward to NST releasing the rest of the set.

About the torque thing though--earlier post said less rotating mass means less torque, but it feels like more... How does less force to get the thing spinning affect torque? Or am I just confused about how torque works? Only explanations I can find online have too many mathematical equations...

Thanks for the kind words! Your experience only adds to what others have been saying up to this point, and we are happy to hear more positive feedback.

And regarding your torque question, take a look at some of our dyno testing we have done on different applications. You can see that the entire power band has been shifted up at every point in the RPM band. NST kits provide more HP and more TQ at every point you look at. Less rotating mass on the engine itself will always lead to such results...

ACURA TSX




INFINITI G35


LOTUS ELISE (has some of the lightest OEM pulleys I have ever seen!)





Don't forget, NST is the only company building pulleys that is actively involved in testing products in RACE CARS. We have several NST sponsored cars in pro road racing and drift series accross the USA.

Our products are built and tested on race cars as well as street cars. We do not build products unless they provide real world gains that we can clearly observe in our testing.

[tk-421]

Originally Posted by NonStopTuning

Thanks for the kind words sir.

Actually, I believe this sir is a ma'am.

Excellent info on the dyno runs.
Just had a good chat with Mike@NSTonAIM. Excellent costumer service!
NST FTW!

[kurokoma-kun]

Originally Posted by tk-421

Actually, I believe this sir is a ma'am.

It's ok, politeness is always welcome!

Thanks NST for posting the dyno sheets! I do understand what these mean--I was just getting confused about how torque numbers are derived, could not read rotational mass/acceleration equations; guh, all those greek symbols!