Yea but its NOT an ENGINE damper, so changing it out will not harm the engine. This has already been demonstrated time and time again, try searching here, my350, or 350zmotoring for analysis of the stock crank pulley.

 

here we go again,

people who have the pulley defend it with their life, those who dont say its not a good mod to perform....round and round we go...

 

it's not about going round and round....
I would also point out, that someone with say 10 or 20k on this mod, and using that to prove no ill effects, misses the point of the question and possible issue.

Based on the pics and description posted last night, the water pump, power steering, and alternator are all driven on a solid hub, and the only part driven on the rubber mounted hub is the AC ???

This really doesn't have the basics of a dampend pulley then, unless (and this is a reach) they determined that the AC is the only device with enough 'yank' to have effect, so the back half of pully is rubber gripped....

it is an odd one, engines tend to have fully dampend or solid.... this is a first for me to see a half-dampend....

so the question is - is it for damping, or is/was it just their construction method ?

 

In the other pulley thread somebody said they were going to split the OEM pulley in half to determine IF in fact it had a rubber ring which would support the hypothesis that the OEM pulley does act as a dampener. This was supposed to be the 'final answer' to the pulley dilemma, but I am not exactly sure what became of the test.

 

Yep, that rubber bushing is an elastomer rubber that acts as a damper at various rpms on the VQ. The older VQs have a similiar design. Running an UDP on the VQ most likely will not cause any failure because the VQ's crank is short and the block/crank are super stout and reinforced. I had an UR UDP on my 96 Maxima for about 1.5 years and noticed increased engine vibrations (high order vibrations, grainy) and my car wasn't an ounce quicker over the span of tons of runs and multiple days at the track.

 

yes I actually have yet to see any numbers or evidence regarding the gains in HP from a pulley...maybe someone can post dyno results?? HOWEVER, those who DO have the pulley also state there is a def. increase in acceleration and its a noticeable improvement...something I would like to see for myself!

 

Ivory_G is going to stop by my house tonight and shoot some pixes of my 5AT pulley.

I agree that we are running round and round.. if not for the simple fact that every time someone asks a question on this topic, we have a bunch of folks quoting old/non-related info (Denon article), do not have the mod - but have a comment, and/or are reiterating hearsay.

Those of us who have the mod, have done oil analysis/tests (repeatedly) and have run the mod street and track for 20k miles & counting are seeing no ill affects.

I was supposed to see my engine shredding itself. If that were a FACT (not hearsay) I would not be receiving an email from Blackstone Labs with positive reports saying "Great wearing engine Ted!"

For those that keep posting that this is a bad mod, please post up just one oil analysis that shows the UR Crank Pulley is destructive/hard wearing to the engines internals. And I say UR, as I will not put my name to any other pulley that I have not installed or run tests on.

Otherwise, please consider stopping your continual promotion of inadequate or misleading information. Only those that run & test the mod --- or endured a non-FI'd CATO'd engine first hand with only the (enter brand name) pulley as a possible cause, have the proper reference for posting real information in these pulley threads.

Lastly... "scientifically" thinking to have a proper comparison for the what the [enter brand name] pulleys actually contribute in HP, you need a control dyno on a coupe / sedan (6MT & 5AT) with no other performance mods. Then you need dyno's for the [enter brand name] crank pulley.

Unfortunately, most folks get around to the crank pulley after multiple other bolt on mods. I myself (see current mod link below) have dyno'd with a group of G35drivers (and have been published in Sport Z Magazine) at 264.3 rwhp in my 5AT sedan - - - with the sum of all my mods. Most recently, I have converted the 5AT crank fan to electric fan.

Now I pose this... the crank fan is driven not on the crank, but BY the crank. If I removed this from the load, am I not toying with the "balance" of the crank system?

And if I am, why do 6MT's come as e-fans, stock? Does Nissan do something different to our cranks? Again, this is just curiousity and welcome discussion on this aspect.

Cheers, Ted

 

Didn't really say it was something. It's just that I have more miles on my car than most of the other people had posted with no problems. And being that I'm not going to keep this car up to 100k, I'm not too worried. And the last time the car was in the shop because it sucked some water into the engine, they got it started and running. They gave the car a complete check, and nothing was out of the ordinary aside from the water being blown out of the spark plug holes. Eventually the wrong motor oil is going to do something bad to the car, or the wrong air filter, oil filter, whatever. I'm sure if there was a mod out there that was proven to ruin your engine in less than 20k miles, people wouldn't get (maybe some would). You only hear rumor about the disasterous effects of what could happen. Why did we even buy a car that needs a dampner? Guess we all should've bought BMW's or something with an in line 6 right. Then we wouldn't have to worry as much. Bottom line, if your modding your car, your doing something most of the time that is shortening the life of the engine in the first place.

Later,

Ray

 

true, some mods are asking for trouble if done incorrectly (FI, Nitrous, v1 Kinetix plenum)

But things like adding an additional oil/tranny cooler, PS coolers, or changing out the radiator to an all aluminum double core will add years/miles to your engine's life.

We should be sure we do not scare folks out of modding, but we should also be responsible and warn with proper real-world information.

 

Point taken and agreed.

Later,

Ray

 

I like you Ted (like that matters) - I mean it is good to see someone thinking things through.

I came into all this injust the last few weeks, so I am looking for info, data, COMMON SENSE...

If anything at all - I am most curious about the design at this point. It is interesting.
IF (and I say if) the intent is to act as a damper.... why only a small part of the thing rubber mounted ... it just doesn't add up...

I gotta believe a solid pulley here makes no difference. If the entire thing were rubber mounted that would be a different story...

also, FYI - my '05AT Coupe is all electric fan - hadn't tought about it till you mentioned it...

 

Hey now... there's another forum for stuff like this. I just don't think that forum can be found on G35driver.

All of this pulley talk has got me ready to go get one, yet again. Wonder if I'll actually install it this time?

 

neffster: don't tell my wife or girlfriend I like Ted... shhhhh....

I will likely try a pulley in a few weeks, I am hoping to have my cats so I can put them in this weekend (we'll see)

Then I will drive it for 1 or 2 weeks... then try a pulley, and see what I see/feel
To some extent I am just curious, particularly about the design of the stock one.

I will ikely have to start screwing with electronics in the car at that point. I am not sure I want to hassle Headers I might do a Y-pipe, we'll see how the cats go.

I am currently trying to determine all the things I want to do from a functional standpoint with the controls/electronics.
- VDC memory
- Full window Control from Key Fob (not just down)
- Maybe sunroof control from Fob
- Dash Indicator for Headlamps/fog lamps
None of the functions/processor/circuit work is hard, but install/connect points are always a pain.

 

It's pretty amusing that some people continue to claim that the stock crank pulley is some sort of holy balanced piece that maintains engine balance. Yea, that's why they use a cast piece of metal and glue on a rubber ring that doesn't even go all the way through the pulley. Yea sure that argument holds up LOL

 

Sickone enjoy the pulley and remember just becasue someone HERE hasn't said they've gone 100K with no problems doens't mean it hasn't happened. The Maxima sites all have several members with gobs of miles and tests and after all these years not one failure has been attributed to an underdrive pulley. If that glued on rubber was saving my engine then dammit I'll just buy a new one every 200,000 miles!

And good point re the people who do it after many other mods. I did it after the plenum and maybe a CAI was on it at the time and I noticed a pretty significant difference that was noticeable and assisted me an a 14.2 1/4 mile run the following week.