3SX Pulleys: Need Feedback

[Stealth1109]

The whole power thing has to do with the inertia (and rotational momentum) of the object. Compressed into its most basic idea, the more weight something has and the farther the weight is placed from its rotational center, the more torque you have to apply ot it (in this case, the torque is provided by the belt). So, a lighter pulley with less weight concentrated on the outside will require less torque from the belt to turn it the same way, thus freeing up some power (in theory anyway). This is the same reason a lightened flywheel works well, because the same amount of power applied to a lighter flywheel will get it turning much more quickly than the heavy one since it has lees intertia.

[theonlypheonix]

you know guys, maybe one of these days you'll convince me but then again you really don't have to either Its just that you see all these claims for this product whether the unorthodox, 3SX, or some of the less known brands but where are the dyno numbers on our cars??

There was just an article in one of the magazines, they did a dyno test on some other car, I forget, with one of the underdrive pulleys and at 6000- 7000 rpm there was around a 7 HP gain. But this was an underdrive pulley and the increase was due to the slower turning accessories (underdrive), therefore less
parasitic losses. Unless your at the drag strip or AutoX, how often do you hit 6-7K rpm? Ok, some of you do on a daily bases and for those of you that do, ok you get 7 HP at 6k rpm. Then theres the rotating mass point, this is easy to understand, simple physics. Yep when you accelerate it will require less HP beause your about 4 lbs lighter, but in HP terms not very much.

If you really search the intenet for the topics of harmonics, they are brought up for every type of engine, auto, aircraft, boats, etc. True dragsters rebuilt the engine every race or at least after a couple races. I not ready to rebuild my engine that often. Look at it another way if your planning on making some real HP you will replace your pistons with something like JE's Now if you run 10 hp more then stock with JE's and your engine blows up, not a very good mod, right?? In my terms a good mod is a performance enhancer without negative side affects and certainly its not a performance decreaser.

Alright, alright I'll quit

[Audiophobe]

Phoenix, you really are a great guy, but when I asked about the dyno numbers on your header deal, you were on me like stink on a monkey. Now with the pulley, you want data!

[homer3000gt]

search the board, numerous discussions about pulleys.

1. stock pully has a harmonic dampener.
2. 3SX, orthodox dont
3. Busch DOES
4. excessive engine wear WILL be caused by pulleys w/out harmonic dampener
info

[SUTHNR]

Here's DYNO numbers.

http://www.3si.org/portal/forums/sho...t=bauer+pulley

QUOTE:
"Before pulley;
317.0 Max Power
345.0 Max Torque

After pulley;
322.5 Max Power.
351.8 Max Torque.

Final runs made at 1.2 bar. With 116oct Fuel.
355.5 Max Power
399.1 Max Torque (I wanted 400)

The HP and torque jump was unbelievable from 1.0 to 1.2. Remember it doesnt hold that boost for long, it drops back to 1.0 bar by 5000rpm.

I quess we all know now how MUCH the pulley helps.
5.5HP AT THE WHEELS!!!!
6.8TQ AT THE WHEELS!!!!"

EricB

[theonlypheonix]

Audiophobe, sorry it was not meant to come across as a . The headers are brand new, in fact not even made yet, how could we have numbers at this point? For now best guess is using the numbers from a similar engine in the eclipse. Now these pulleys, esp the unorthodox, however have been around for a some time.

I guess what I'm saying is that I would like to see our suppliers, developers, and manufacturers take a little more responsibilty for the products they are selling us I'll will be trying to get Vision to supply us with dyno numbers for their new headers. I think its only proper from the development side of supplying quality parts.
Maybe I've just spent to much time in development and an expecting tooo much of other developers??

Ok, SUTHNR that's great but is there any similar numbers on the 3SX pulley which is not an "underdrive pulley" ?? Maybe on a non-turbo besides.

[Bluv69k]

got mine on today and it runs great. Hard to tell the increase since I also installed new turbos.

[SteveVR4]

More Dyno #'s
http://www.unorthodoxracing.com/dyno_maxima_2002.html

I know this is a Nissan, but it is an NA with similar setup as 3S NA's . There also are many more #'s posted as well.

As far as the 3SX pulley, here is what Unorthodox says about pulleys:

"Unorthodox Racing lightened underdrive crank pulleys on average can provide gains of 5 to 12 HP and 4 to 8 lbs.-ft. on normally aspirated engines and 8 to 16 HP and 8 to 18 lbs.-ft. on forced induction engines. Higher gains are possible. For example, a Nissan 300ZX twin-turbo saw gains as high as 37 HP and 45 lbs.- ft. on the dyno just by replacing the stock crank pulley with our Ultra S lightened underdrive crank pulley.

Power gains are obtained in two ways. First, and most important, is the weight loss. An average of 2.7 HP is gained from every pound lost off the crank shaft. 85% of our gains are from weight loss.

The rest of the gains are from underdriving, which accounts for about 15% of the total gains. We do not push underdriving for two main reasons. Our main reason is to keep charging systems, air conditioning, power steering, and water pumps moving fast enough for every day driving. Second, not much horsepower is gained from extreme underdriving. In most applications all of our underdriving is done with the crank pulley, not the accessory pulleys. This is done so maximum weight loss can be achieved at the crank where most of the horsepower gains are found."

Hope this helps to clear up some issues as far as HP anyway and 3SX's pulley

Steve

[SUTHNR]

Originally posted by theonlypheonix
Ok, SUTHNR that's great but is there any similar numbers on the 3SX pulley which is not an "underdrive pulley" ?? Maybe on a non-turbo besides.

Probably 1 hp less than the Unorthodox as the UD is only 3 ounces lighter. As far as hard numbers, 3SX does not have a dyno - there is one right across the street (2wd dyno) but I can;t seem to keep the crank in the car long enough Turns out this time is was apparently a WICKED bad turn on the flywheel - turned at an angle - nearly destroyed a clutch in 300 miles, and I'm convinced it's was threw out the crank and bearings so fast. Friggin machine shops......

Now the adjuatable cam gears... We did get some numbers from a customer - said he dyno'd the car, installed the cam gears, and redyno'd the car. Picked up 28 ft/lb of torque!! Not much on the HP side, but good for torque. That was a TT customer, running +2 advance on intake cams, and -3 retard on exhaust cams. NA guys are running similar/same setups but haven't received any dyno feedback yet.

EricB
Hopeing to get my car back before the next millennium.

[theonlypheonix]

thanks Steve and Eric for that clarification, I do realize that you are posting info from the Unorthodox web site. And that generally dynos don't lie but then there are tolerances in any measuring device. I guess where I get stuck on this is that from basic physics principals one can not explain how this HP is being made from just reducing mass. From underdriving that is easy, you are not putting as much HP in the accessaries. But from reducing the mass?? Well unless you're running the bearings "DRY". The only way there should be any appearant HP increase would be only under acceleration. Simply stated a mass at rest stays at rest and a mass in motion stays in motion unless acted upon by an out side force, otherwise you have some pretty high friction bearings.

Being an engineer myself I know there are ways that we, as engineers, play with the numbers to kind of present things to make the point that we want to make. Anyway I sent off an e-mail to Unorthodox to try to get them to explain how they arrived at the claims they are making. Thanks anyways.