Please enlighten me

NonStopTuning · 04-11-2011, 05:58 PM

Quote:

Originally Posted by ChipsWithDips

What sort of bmw engines? From what I've heard and read, harmonics play a more important role the longer the crank is. If they were I6 that's a big difference from V6.

I'm still curious what the harmonic frequencies of a given crank would be and how those are determined. The hope is that the frequency is high enough for our motors that it's only an issue at a rpm higher than we are using (10k or something)

This topic has been discussed in great detail in the COMPREHENSIVE NST thread, linked above.

As a very short review...

1. No one has ever reported engine problems with NST pulleys for the 180SX, 240SX, 350Z, 370Z, G35, or G37.

2. The 370Z engine is internally balanced and the crank pulley does NOT serve as a balancer. Some engines do, this one does not.

3. When it comes to the natural harmonics/vibrations, the RPM range where the second (dangerous) wave could/would occur in such an engine would be near/upwards of 10,000rpm. A range that this engine will not see.

This is not a BMW engine. There are certain engines that we do not choose to build pulleys for, due to the concerns of vibrations and the concerns that certain communities have... whether valid or largely based on theory. The Nissan community has been using NST pulleys for years without issues.

To remind everyone again, we use our own products on professionally built RACE CARS that live at redline on race tracks. We use our own solid pulleys on these very cars. In order to be competitive we need these engines to be powerful, rev happy, and most importantly, RELIABLE. We would not use our products on these cars if they were not safe.

Much more info in the COMPREHENSIVE NST thread...
NST (NonStopTuning) 370Z VQ37HR Pulley Kit Review w/ Dyno Charts