Hey... i'm not finding a whole lot on the specifics of installing and effects of underdrive pulleys on a Z.

Really this is just an experience question...

Can you guys tell me what you noticed on your own personal installation of U/D pulleys... How about the efficiency of your other components, dim the headlights? interior lights? etc. Just let me know how it worked out for you.


All my experiences is with V8 domestics So be easy on me.

 

Oh and how about the risk of internal damage from altering the Crank pulley?

 

For me. No adverse affect at all on anything electrical. A/C is fine as well.
If anything, revs more freely.

There are posts that suggest a pulley could lead to damage due to the loss of the harmonic balancer. Bit none of those were first hand. No one has posted anything negative (that I have read) only good.
I suppose it could have a long term impact several years down the road.

Well worth any small risk IMO.

 

i have a UD pulley on my na. The only problem u will face is when u are running a large sound system. I am pulling over 1200 watts and with the UD pulley i have been goin through alternators like crazy..plus the electric fan doesnt help either. i remidied the prolem with two 1.5 farad capacitors.

 

Performance wise its all good but the only thing that i have a problem with is the underdrive pulley on my alternater. because i have a sound system in my car the lights on the dash tend to dim when it is turned up and the sub is hitting hard.

 

So what is the best remedy for this? is there an upgraded aftermarket alternator available? Or would capacitors take care of the problem? completely... cuz i'm going to be running 1000watts or so... not really a need for more... plus i take the speakers out on race day

 

I've heard the same about the Harmonic balancer, but I think it was in Z1's tech files where they mentioned that the underdrive pulleys on the VG dont use a harmonic balancer like most traditional V6s, so Im pretty sure its ment to not come w/ one. I'll have to look around where I read that, I found it pretty suprising when I heard it since there has been so much debate over the balancer.

 

The VG30DE and VG30DETT engines have a "Harmonic Dampener" not a "Harmonic Balancer"

"Harmonic" is refered to the vibiration that a engine crankshaft produces at a certain RPM. In order to do any internal damage to either the crankshaft or the main or rod bearings you would have to run your engine for a very long extended period of time in that RPM range that produces the Harmonic Vibration harmful to the rotating group of your engine. (if it is internally balanced)

It's been said that with the UD pully, you'll wear out your crank and rod bearings due to harmonic vibration, not true, you run a greater risk of developing a stress fracture along one of the bearing journals which would break your crankshaft inhalf. Which is still highly unlikely.

"Harmonic Balancer" means, that this device is used to counter react the vibrations of a unbalanced crankshaft, and yes this type of engine could see damage at a faster rate over an internally balanced engine.

"Harmonic Dampener" which again is used on the VG30DE/TT engine is for the dampening of the Harmonic Vibrations that would be transferred from the crankshaft to the belt driven accessories such as the Alt, Power Steering, Water pump, and A/C. This is an attempt to get these devices to live longer.

I for one have had a UD pully and a aluminum flywheel for over two years now and have loved every revving RPM minute, so far with no ill effects.

If you're still are not convinced, go to any internet search engine and type in "Harmonic Crankshaft Vibrations", it's amazing the reading material that is available.

Of course you get those that say....oh....UD pully BAD......and others say...well you get the meaning.

Good Luck
LATER