Long story short, I found out my old buddy Mike from www.NonStopTuning.com was in the process of building some new pulleys for the TSX and offered my car for testing. From the NST website...

The NST Acura TSX pulley kit increases horsepower via great weight reduction and the underdriving of accessories. Superior to other available kits, NST kits also offer an Overdrive Alternator Pulley to optimize output for stereo system lovers!

^^ This is really a plus for people like me who want to add a nice audio/video system in the future, because the NST alternator pulley will charge the battery and run the electrical system just like the stock setup!!!

Each kit is carefully crafted from 6061-T6 aircraft aluminum, tested and balanced to high tolerances. Every NST pulley is hard anodized for exceptional durability and is available in a choice of colors: Blue or Graphite Gray.

Here are a couple pics...





http://www.nonstoptuning.com/pKitHonTSX.htm

 

at last, any dyno sheet results?

 

 

DIY pics? Dyno?

 

And a quick pictorial of my installation...

 

Dyno sheets and charts coming very soon...

 

there is no replacement for the large pulley?

 

It looks to me like they left out the splines in their pulley. So they're relying on the "key" to drive all the accessories?

IMO, that is a bad design. You're putting all that force into the key. When the key breaks, you'll lose power steering, and your spark plugs will get the juice from the battery rather than the alternator, and eventually your car will shut off once the spark plugs consume all the power from the battery. The splines actually reduce the stress on the key and distribute the force to the "teeth". Since there are more "teeth" and the force acting on each of them is less, it is less likely for the teeth and/or key to break.

Anyway, just my

 

What's the part number of the shorter accessory drive belt that is required for the NST pulleys?

 

Count me as curious on the dyno as well. Please post!

 

Also, its a little dissapointing to see the pricing. That's not really 'beating' UR considering you're basically getting 2 pulleys for $200 instead of 3 for $275. There was quite a difference in the weight of the stock PS pulley vs. UR's as well, so I'm sure they're realizing extra gains there.

Still, always glad to have more options and products. Want to see the dyno now.

 

Overdriving accessories means more loads on the crank pulley. It seems counter productive... Why not simply keeping the stock alternator pulley if worry about voltage drop?

 

You need a smaller alternator pulley when using a smaller crank pulley in order to keep the alternator's rotational ratio the same as stock.

 

Yes, but by doing so, it reduces the effect of underdriving the crank pulley.

 

Is the belt the same width as the stock belt? It doesn't seem to cover the entire PS pulley width...

 

Not too excited about this one.

 

The UR ones look like they are higher quality imo.

 

since when did jtso started making incoherent posts?

 

If this pulley setup was supposed to be at a better price point than UR pulleys, then why didn't they make a powersteering pulley with the kit and offer it for $250? Only offering the crank and alt pulleys will not show accurate comparison between the two products. Dyno numbers are a must, and more information on why the splines were left out of the crank pulley would help support the product....

 

UR crank pulley doesn't have the splines either. It's becasue the stock crank doesn't use them.

 

The UR's dont have them either

 

Why would the stock pulley have them?

 

They have in fact left out the splines. As others have said, even the UR crank pulley has no splines in it. In fact, many OEM Honda pulleys have the spline design and none of the aftermarket pulleys over the past few years have duplicated this.

If you look at the pic that JT posted you will see that the actual CRANK does not have the splines on it. So if the crank does not have splines, then the crank pulley does not necessarily need them either.



I agree, the keyway does look pretty small and that may look a bit scray, but this small keyway is more capable than you think. If you take a look at older Honda B series, H series, Toyota, Nissan, etc. you will find that many of those motors actually had much larger pulleys but had very small keyways. The small keyway is very capable and will last under the loads that are put on it.

 

You will actually not notice any difference in horsepower or torque this way. We are talking about a neglibable amount, maybe half of one horsepower.

Your sender pulley, the crank pulley, is the one that determines how much power is sent to your accessories. The receiver pulley, your alternator pulley, uses this power in a way that is relative to the pulley attached to it.



Your crank pulley at the bottom is the sender pulley and is responsible for sending power to the accessories. When you decrease the diameter of the crank pulley you are making the associated accessories run slower, which is called underdrive. Pleople who have experience with bike gears can understand what I'm talking about here.

Now, if you also added a larger accessory pulley to the mix, like the UR alternator pulley, you would further slow the alternator.

If you want to slow something down you can either do it with a smaller sender pulley, a larger receiver pulley, or a combination of both. The UR set has an underdrive crank pulley, plus an underdrive alternator pulley. The result is slow plus slow = slower alternator. This is usually not a big deal, it becomes a problem however, when people run large audio/video systems, extra lights or HIDs.

NST uses an underdrive crank pulley because it is the sender pulley. The sender determines what speed the accessories spin at and how much horsepower is used to spin them. But at the same time they use an overdrive alternator pulley (no, not bigger than the stock one) to speed the alternator up and make it more efficient. This is excellent for people with large systems etc. because their alternator now works just as it did when everything was stock.

 

I agree with other posts, the end of the crankshaft is smooth, doesn't take advantage of the splines. In addition to the key (which is driving the alternator and p/s pump, not exactly high-load items capable of snapping a steel key), there's also the bolt which is tightened to approximately 2 million lb-ft. My guess is the splines are left over from other applications using the same crank pulley that do utilize the splines.

 

Yes, absolutely, the driven pulley runs slower if the size is larger. Most people have only addressed the the rotation speed but not energy required to rotate the pulleys. Now let's get on a 10 speed bike and do some comparison. 1st gear is small gear front (driving pulley), large gear back (driven pulley). This is the typical UR pulley setup. The driven pulley is moving slower as a result (known fact). However, it also makes the biker (engine) to pedal easier (engine spins faster) with less effort than if you would moved the rear gear to the smallest (5th gear). Which bike gear setup would allow easier pedalling for the biker (engine)? Keep in mind the "primary" objective when installing underdrive pulley(s) is to allow the engine to spin easier. This is best accomplished by utilizing both front and rear gears if possible to get the maximum result. Accessories being under driven is a trade off for more power. If the sizing is done correctly, the negatve side affect of low voltage output can be reduced.

 

I agree with everything you just said in that reply. In fact, I have done quite a bit of reading while I have been on these forums and I can see that you are a very educated man when it comes to the TSX. You definitely seem to know quite a bit about these cars and performance theories in general. Keep up the good work

Like I said earlier, and like your test data has shown, slowing the alternator at the speeds that the UR kit does is not necessarily a bad thing. In fact it is great for a car running a stock electrical system. The problem arises when people upgrade their systems without taking this into consideration. Numerous people on other forums and in general, have expressed concerns about UR kits dimming their lights or not charging their batteries well. This has unfortunately led to a stigma about pulleys in general. But I hope you agree that the NST kit does provide a nice advantage for people who like to run subs, aftermarket stereos, screens, etc.

Both kits are great, I just think that the NST route is a good mix of "best of both worlds."

I am looking forward to seeing dynos from a few different people with this kit just like the rest of you

 

Yeah JTso, that belt is a little smaller than the power steering pulley. NST recommends using K070673 with their pulley kit but on the day of my install I could only come up with a K060675 at my local parts store.

By the way for everyone interested, NST will be looking into building a new power steering pulley for our car pretty soon. When my new PS pulley is ready to be installed I will be sure to use the correct belt

 

hp curves
[


torque curve



i have the dyno files monday so i will post those then.

 

Its getting late so im going to head out, I have notice my typing is getting bad meaning its time to sleep goodnite all for today.

 

 

that looks very promising!

 

wow

 

Those dyno numbers look very promising indeed

 

Very smooth and consistant gain throughout the whole powerband. Seemslike the peak power in hp and tq is around the 6500rpm mark which is vtec....

Seems interesting. Though we would have to wait til the steerting pulley comes out and see what #s it pulls and what the pricerange it would be priced at.

 

The power gain in the dyno chart was as I expected, but not the torque gain! That is a huge torque boost throughout the entire rpm range up until the top, a similar effect to a lightweight flywheel.

 

does anyone have a UR pulley dyno for comparission?

 

I'm happy with UR pulleys.

 

Raheel616 what other mods are you running on the TSX could you list them pls?

 

Injen CAI..