Lightened pulleys etc

Hey guys is there any difference between 300zx year models with the pulley's?

looking at

http://cgi.ebay.com/ebaymotors/UNDE...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

And alot of other listings have it from like 90 - 96 the same (even some NA and TT the same) but these guys seem to be speciifc, would it fit a 91 TT?

 

PZP where art thou?

You could wait on PZP to start selling his, or I would suggest trying to get on a AMS at par deal and get theirs roughly 360... but they are black which is sorta putting me off... polished aluminium is what I want.

 

Ditto

Been watching PZP's for ages but my conversion is happening in 2 weeks so I need the gear before then.

 

Don't quote me but i think i might have heard that the 95+ have a different pulley for the alternator... might have something to do with this one being so specific.

 

In a 95+ Z, isn't it a 3 rib belt for the P/S gear because of electric HICAS?

 

there are differences with the alternator and power steering pulleys based on the year of the car. courtesy of AMS:

300ZX PS Pulley - 322-1 (90-96 NA;94-96 TT)
300ZX PS Pulley - 322 (90-93 TT)
300ZX Alt Pulley - 321-2 (94+ TT)
300ZX Alt Pulley - 321 (90-93 TT)
300ZX Alt Pulley - 321-1 (90-96 NA)

contact AMS at www.amszstore.com and they'll hook you up nice.

 

Lighter alt, power steer and air con is all good. If larger than factory pulleys then it is better again if high reving big hp car, mainly if going to race track it is also good to slow everything down. This means less power drag and better for less power steering heat. One piece light crank pulley is not good for crank bearings though, as nothig to absorb vibratiion if harmonic balancer is removed.

 

An UDP will slow all accessories down ..no need to put bigger on others

I am yet to see a vg30dett get damaged from an UDP .. any real evidence?(gtr's dont count)

 

I have larger than stock water pump, power steer and alt pullleys, and an under driven harmonic balancer, as high reving race car.
Why risk it Rob. There is no evidence to say it is ok for the motor either. No facts, and no decent mecanic, or engine machine shop, or mechanical engineer, would say it is good either. The only ones for it are forum flyers and people selling them. No dyno figures to prove it either. Zeds get away with it as short crank, and GTR's all fail with one, and very relavent even though they are more prone to vibration as they have a longer crank. It does not mean zeds being V6 don't have harmonic problem, just a lot less. Vibration robs power to remember. The engine could actually make less power with one.

More info on a previous thread here.
http://http://www.aus300zx.com/forum/showthread.php?t=268294&highlight=cams

 

Hi Rob260, yes he did and we fitted it and I warned him of the potential problems, we ended up refitting his OEM harmonic balancer. Although I know many zeds have them fitted and no problems, or none obvious.
I also know of an engine shop that does the od race motor, and engine dyno tested a Holden race motor, that lost power with a billet alloy engine pulley.

BLACK BEAST if you are coming racing wth us, with a big hp motor, then rather than spread parts all over the track, leave the factory black harmonic balancer, and get it balanced, as they are often out, or better still get our blue race harmonic balancer and have best of both worlds.

 

The harmonic balancer is designed to dampen or restrict torsional vibrations in the crank shaft. Removal of the harmonic balancer will typically result in the breaking of the crank between pistons 5 and 6.

 

make those ross balancers in silver or red JP n I'll get 1!

 

From the hundreds of direct installs we have yet to see any evidence to support increased wear of the VG30 Crank with the removal of the 'Torsional Dampener' (Crank) which weighs some 13 lbs!. We've been installing the light weight units from their inception back in the day and zero first hand evidence even in motors that were freshended up (rebuilt) after the initial build. The Z does not employ a 'Harmonic Dampener' as the engine is internally balanced unlike the old school motors and some other imports that use the pulley to balance the assembly. Now if the motor was not properly balanced by a machine shop to account for the Wiseco Pistons/Eagles Rods or other equivalents then I can foresee issues.

Just giving some first hand experience with pulleys on the VG motors we have built over the years

Here is an exerpt from UR's site (http://www.unorthodoxracing.com/faq.aspx#section2):

Is my crank pulley a harmonic/torsional/vibration damper or a harmonic balancer?
People are getting their crank pulleys confused with the harmonic dampers found on some domestic V6 & V8 engines. "Harmonic Balancer" is a term used loosely in the automotive industry. Technically, this type of device does not exist. The "balancer" part comes from engines that are externally balanced and have a counterweight cast into the damper. None of the applications we offer use a counterweight as part of the pulley, as these engines are all internally balanced.

The pulleys on most of the new import and smaller domestic engines have an elastomer (rubber ring) incorporated into the pulley making them look similar to a harmonic damper. The elastomer in the OEM pulley serves as an isolator, which is there to suppress noise from the engine accessories; the A/C compressor, P/S pump, and alternator. This is what the manufacturers call NVH (Noise Vibration & Harshness) when referring to noticeable noise and vibration in the passenger compartment. It is important to realize in these applications, the elastomer is inadequate in size and durability to act as an effective torsional damper. If you look at the pulleys on some imports there is no rubber to be found at all. We have samples of these, mostly from Acura/Honda B & D Series engines, Nissan Altima, 1.8L Eclipse, 2.3L Fords, Chrysler 2.2L's, and 1.8L VW's just to mention a few. Most owners who have installed our pulleys notice the engine actually feels smoother. This is result of replacing the heavy crank pulley with our crank pulley. NVH is variable and unique to every car. NVH will increase with the installation of an aftermarket intake and/or exhaust, for example. Think of OEM intake systems in newer cars, they use baffles and resonators in the intake to quiet all the intake noise. Aftermarket intakes eliminate these resonators and create dramatic increases in engine noise from the throttle opening and closing. So to most tuners, certain types of NVH can make the driving experience more enjoyable.

The purpose of a traditional harmonic damper is to protect against crank failure from torsional movement and frequencies of high amplitude. This is not necessary in most modern engines because of the many advances in engine design and materials. Factors such as shorter stroke length, smaller displacement, piston dwell time, piston pin off-set, power output, etc., do determine when and how these harmonics and torsional movements occur. More importantly the actual tune of the engine, espcially with modified vheciles, is the biggest factor in potential engine damage. Poor tuning leads to detonation which is an engine killer that no damper can stop.

Again, there is a lot of internet hearsay about solid crank pulleys. When engine problems occur, too often people are quick to blame the pulley first, rather than taking the time to look logically into why there was a problem. We hope that after reading this you will understand our crank pulleys better. Top

 

Bolts what do you mean by typical? Ive seen many many Z`s with light UDP`s and ive never heard of any crank problems. I would assume that typically there is no problem.. and that it is rare to find a problem ?

 

It all sounds good but why did Nissan and other OEM use multi piece crank pulley, with rubber, and havey for areason also, and it is a harmonic balancer. No hearsay the Zed harmonic balancer is the same as what GTR's use, and as mentioned on GTR's all fail if solid pulley is fitted.

Not hearsay or stories, this is how the facts of physics, and engineering, not bling talk. On most Zeds it is hard to notice the added vibration that is increased, whilst other cars is very noticeable. For the questionable gain, why add vibration to your car, and potentially wear out the bearings faster? It is hardly seen and better to use a lightened flywheel and other pulleys, with no disadvantage.

Finally WhiteNigth and others, NO it is nto teh end of the wrold and plenty fo zeds run non harmonic balancers solid light weight pulleys with little to no issues. THere are defenite cases I knwo fo in big hp cars that had issues with bearings, but if not big hp and not raced then you get away with it. BUT for what gain to risk ratio.

 

Well we call it a torsional dampener in our trade here Used to dampen unwanted noises and not balance the crank as a Harmonic Balancer does. The VG is balanced internally as stated prior. As for the Inline 6 on the GTR it is a totally different motor and very susceptable to vibrations at higher RPMS and failure even with stock Pulleys.

Once again I speak of our experience 'directly' so you may have different first hand evidence for the VG's or preferences? All our high HP builds have used these with zero failure rates to date since the 90's. As such I see no evidence to support hightened failure rates with the use of a lightened pulley from our sphere.

Regards,

Vuk@AMS
www.amszstore.com

 

In the rare case that if the crank fails without a harmonic balancer it would typically be around pistons 5 and 6.

 

Correct very few failures, although quite a few with increased vibration. It is more of a problem if big hp, and driven hard circuit racing. Talk to an engineer rather than sales guys re the facts of why it is not good to use these, although plenty do with little problem. I still say why would you?

I even fell for the sales pitch many years ago and had one on. Later getting it modified by Ross balancers to make it sort of a harmonic balancer, with vulcanised rubber, then going back to stock before getting the Race homonic balancer as per below blue one with Alen key bolts and vulcanised rubber.

 

I had a light weight alloy pulley for all of 2 weeks. There was a definite increase in engine harshness. IMO that cant be good.

Changed it back to the OEM pulley. Its obvious this is how it is meant to be.