much like a lightened flywheel/clutch, there is actually no inherant HP gains per se, but the engine revs so much smoother and faster than before... you really have to watch the needle to keep it from bouncing off the rev-limiter...

I have 10K+ miles on mine and I've had zero problems (the belts squeeked for about 3-4 days, then I tightened the belt and everything's been perfect since)

2003.5 BS coupe 5AT
Clear Corners, Alum. Pedals, Pro-1 Intake, Resonated Test Pipes, UR Pulley, CF Engine Cover, GReddy EVO II, Kinetix Plenum, Hotchkis Sways

 

No problems at all here, i love them!!
14.5k miles here!


Martin
2003.5 BS G35
Nismo Aero/Sport Package
0-60 5.4 - 1/4 Mile 14.16 *GTech* and on 19's!!

 

My personal slant on this issue is that I will not be installing my pulleys until AFTER the factory warrenty is over. It's not worth taking the chance that IF I do develop any engine/alt/AC/or who knows what else..... problems. Having my warrenty voided because of a undersized pulley, whether it caused the problem or not, is just not worth it. In my discussions with a Infiniti service manager, it was recommended NOT to install the pulleys as ANY warrenty issue will be DENIED. The MOSS act will provide you some protection, but at a cost for a lawyer, that could easily cost more than the repair.

But it's up to each individual to decide on their course of action. Mine is not to install until the warrenty is over.

2003 G35 6MT DP Willow
Mods:
Aluminum pedals - Sirius radio
Rogue short shifter/titanium shifter
Z-tube/K&N filter

 

There was a lot of debate i've seen about the Dinan article. Most of his work or theory is based on a straight six engine I believe. With a much longer crank and completely different pulsation characteristics I wonder if that theory can even apply to the perfect V angeled short cranked 6 with internal balance?

2003.5 DP 5AT Sedan
14.2 @ 97.18
Z-Tube
K&N Drop In & Airbox Mod
10 Wire Hyper-Ground
Crawford Plenum (V4)
UR Crank Pulley
Hotchkis Sways (M/M)
Polk EX-3500 Tweeters/Shock Sensor/H-Liner

 

It's not theory. Engineers can and do measure vibrations in engines. Exceeding the speed of light is theory. How much vibration occurs when a pulley is damped can be measured and is measured. I have no personal evidence that Nissan has measured their vibrations but I can confirm that engineers at Caterpillar do measure theirs. I think it's reasonable to assume that Nissan does the same.

2004.5 Coupe/5AT/Ivory/Everything but front spoiler/Nismo CAI/Crawford V5/Crawford Cats

 

Could somebody answer me this?

If an aftermarket solid pully doesn't increase apparent engine vibration, why would Nissan go through the trouble, cost and decreased performance of adding a heavier pully with a layer of rubber sandwiched in the middle to damp out vibrations?

Why does Nissan have it if it is not needed and it only adds cost and only decreases performance?

2004 G35 6MT Blk/Blk Sedan Stillen Air, Stillen Exhaust

 

Are the Nissan engineers just stupid. How or why did they come up with this crazy idea to arbitrarily add rubber dampeners to their crank pully?

2004 G35 6MT Blk/Blk Sedan Stillen Air, Stillen Exhaust

 

No hard feelings guys. I just have to ask the question.....

2004 G35 6MT Blk/Blk Sedan Stillen Air, Stillen Exhaust

 

no hard feelings here. IIRC, the rubber 'dampener' does not go all the way through the pulley. (I'll have to go home and check it out again.) It is just on one side of it. If this is the case, I guess we could just glue some rubber on one side of the UR pulley and call it good. No?

 

1 other thing: to anyone who has FI, does the pulley with your kit have a dampener attached to it? My guess is that they don't. I asked this question on a different thread but no one answered it. If this 'dampener' is so critical to the engine's health and longevity, why aren't the FI manufacturers adding it to their pulleys (if indeed they are not.)

 

If you can achieve the same resonant frequency and damping factor then probably yes. Good luck.

2004 G35 6MT Blk/Blk Sedan Stillen Air, Stillen Exhaust

 

sorry hydrazine. My 'question' was not really a question but more of an attempt to make a point. I guess it didn't work.

 

What was the point? That the rubber doesn't go through? Weather or not the rubber passes completely through is beside the point.

I don't see any point that adresses the question of "Why would Nissan engineers put a damper on a pully?" Why would they make it of a specific weight when they could have easily made it much, much lighter?

I tend to believe they chose a specific weight, moment arm, inertia and damping factor for a specific reason. To regulate and conrtol the frequency, Q and damping factor of a complex resonating system.

I'm not saying your engine will grenade from UR pullies. But it could reduce margin by some unknown degree.

I could be wrong. Hearing that many, many Maximas use it without problems is good to hear. Its just my cautious thoughts on it.


2004 G35 6MT Blk/Blk Sedan Stillen Air, Stillen Exhaust

 

well, anywas, back to the point of this thread.
has anyone had any engine problems? or know of anyone with engine problems?

the theoretical etc etc has been discussed way too much in other threads. lets try to keep this one non-theory.

G35s6mt/TSecu/350Z Springs&Struts/K&Nfilter+Z-tube/StillenDualExhaust /6WireGroundKit/KinetixHighFlow