Hey guys sorry i figured this thread had died but im unsure as of now if they fit HR's i will find out though as for the stock ones being balanced they only have a small layer of rubber in them to keep the vibration down. Those motors should not have much vibration to them if they do its most likely too late. As for belts i was unaware they were not being shipped without belts although they use stock nissan belts, remember these are not underdriven. i will see what we are going to do about that. thanks guys feel free to pm with questions.

 

http://www.atiperformanceproducts.co.../damnissan.htm

 

yes--there is no gel-fluid in the stock crank pulley--just a rubber ring on metal.

 

Ah.... I are edumacateded.

Thanks man!

 

Did you learn you a book?

 

Well I recon I ain't ready fer dat big uptown book learnin' yet. I's keep jes askin' quesjins an stuff.

 

so what you guys are saying this should be a straightforward install? no adjustments or burping of the ps of that sort? ive planned to get this kit and if its a straightforward install i might just do it myself.

 

just ordered the AMS pulleys and belts
I'll let you guys know how it goes

 

You make the decision.

The Facts

1) The stock crank pulley is two piece unit with a sandwiched elastomer ring.

2) The elastomer ring serves as a damper for certain order crank vibrations that occur during various rpms under load.

3) The clutch assembly or torque converter serves as the damper on the other end of the crank.

4) The VQ series is very beefy with 4 bolt mains and a crank girdle which makes the entire motor, including the crank, very strong.

5) Removing the dampening capability pulley can cause vibrations across the crank. These vibrations can then impact the valve timing and ultimately power.

6) No one has yet so show proof on the strip that the VQ35 pulley works.

7) Do not trust engineering speak from the billet pulley manufacturers because they claim the OEM is not a damper. This is completely wrong.

8) No VQs have been destroyed by a UDP/lightened pulley assuming the pulley was manufactured correctly with a steel key.

9) The VQ is internally balanced just like any motor built after the 1980s. The concern is what the engine, specifically the crank, does when explosions hit the pistons. These explosions place tremendous forces on the pistons, rods, and then the crank. As the explosions increase, rpms increase. As the rpms increase, certain order vibrations occur across the crank. To quell these vibrations, engineers use dampened crank pulleys as well as the cluth/TC on the other end. The term "internally balanced" is a moot point. Be VERY cautious when a manufacturer or vendor tells you "oh, the engine is internally balanced, it doesn't need dampers on the crank". This is not true and completely questions their true automotive knowledge.

10) Underdriving a crank pulley will result is very minimal gains, if any. The biggest accessory drain on the engine is the water pump and that is driven by the timing chain. The AC is the second biggest source of drain and that pulley is free wheeling when the compressor isn't engaged. The alternator can cause significant drain, but the pulley is already very small.


I dare anybody to contest what I've posted above.

 

OWNED! lol

 

fact 3.5 : many 6 m/t drivers swap out the stock "dampened" flywheel for a lightweight one without problems except noise (but somehow essentially doing the same thing as lightened flywheels on the opposite end of the engine is not as well accepted and is more controversial )

And how much dampening ability can an elastomer really provide?

True dampened crank pulleys are the fluidyne (gel filled) and the ati (internal o rings) pieces and they are slightly od and weigh close to stock.

 

its commonly known that DAVEB is against lightweight/UDPs. at this point, ive heard his banter enough that i dont even read it

 

Any of you know the diameter of these pulleys?

 

AMS And Z1Motorsports, all they do is copy other Vendors ideas and products and sell them, some times they do a little change to the products to save face, for example they copy a set of Down pipes from Specialtyz.com and they put a extra set of bungs on them and sold them.
just an example
http://twinturbo.net/net/viewmsg.asp...msg_id=2111944

 

I believe its the same as stock, just lighter in weight

Dave B,
These are not UDP, they are LWP.

Good right up though.

 

How much? Enough. Lots of engineering goes into that little pulley. The TC and clutch/flywheel act as dampers just because of their sheer weight (35-40lbs). Even adding a lightened flywheel isn't going to greatly reduce the dampening capability of the assembly unless you do something silly like add a 8lb flywheel then you're just asking for trouble with a lot of other things I won't bore you with.

For those that have a OEM crank pulley laying around, look on the back side of the pulley and you'll see mutliple little divots. Those divots match the pulley's rotating mass to that of the crank's. The pulley and crank are matched to work together.

As for the fluidampers, that is the ideal set up, but that's too costly for OEM when most people aren't operating thier motors at high rpms for extended periods. A fluidamper is a very wise investment if you're a road racer.

Also, find one real racing team that is running UDPs or lightened pullies on their engines. Do you see them on factory Nissan race cars? Hell no, you see fluidamper units. Think about that for a second.

 

You're damn right. People need to know both sides of the argument. I had a UR UDP on my old heavily modded VQ30. I tested it on the dyno and at the strip (~40 runs). It didn't do squat except introduce more vibration at high rpms, made the car harder to launch consistently, and if anything, actually slowed the car down fractionally in the 1/4 mile. The VQ30 uses the exact same pulley design as the VQ35's as well as any other Nissan powerplant on the market in the past 20+ years.

 

Yeah, forgot to mention that...what is the diameter of the stock pulleys?

 

your improperly installed pulley doesnt make all other pulleys bad.

 

You can't improperly install a pulley unless there's a problem with the pulley. The installation is straight forward and the pulley only fits one way. I strongly doubt you even what you're looking at when you pop open the hood, much less how to remove and install a crank pulley on a VQ motor.

Give me some credit here. I swapped out intake manifolds, three y-pipes, catbacks, ECUs, wired up a vacuum actuation system for the JDM variable intake manifold I installed on that car, axle swaps, plus about 6 changes to the entire setup, plus helped trouble shoot and work on tons of other cars for friends and family. I know what I'm doing under the hood.

Back to your statement that "it doesn't make other pulleys bad." Did you not read my first post. What you've stated is a moot point.