I assume things went south and the resulting pictures are result? I also assume that since you have the key, it didn't come all the way off. But just bent. The chunk of the pulley is probably on the freeway somewhere.

I of course can't say what happened but it looks like the key got bent over, thus causing the timing problem. But does the ecu/engine use the pulley to verify timing? I don't see any marks on the pulley. Unless that's what those small circles are for?

I do think it was an install problem. Now this is only my guess. When you put on the pulley, you have to line up the key to the notch on the pulley. Then carefully tighten everything down. But if the key somehow slides back and doesn't sit all the way on it's notch on the crank, I can see the how a piece of the pulley could break off from the bending of the key. ie.. key is pushed back and is sticking out of the rear of the pulley/crank notches. Now with 50% of the key trying to keep the pulley from spinning on the crank it starts to bend. Now since it's sticking out of the notch on the pulley, the bending of the key also puts stress on the back of the pulley, breaking a chunk out of it.

 

Actually the timing ring is mounted on the back of the VQ crank pulley.

IMO, the failure was related to the fact that this pulley does not use a steel key slot. Instead, it appears the entire pulley is aluminum which is no good because aluminum cannot handle the torque load required hence the reason for the break. Nissan spec ft/lbs of torque is equal to nearly 135-145 ft/lbs.

 

My ASP pulley was fine for the years I had it on. I think if it was the pulley itself, one would see alot more of these things happening. At this point, I vote for an improper install. Because if the key was installed properly and if your theory was true, the damage would be much deeper inside the pulley. Also if the key was installed right, even a large chunk out of the end of the pulley wouldn't allow it to move and change the timing.

 

I agree. All theses complaints seem to be more install related. If this product was so damaging to our cars then why is this product soo expensive in the first place and still on the market? Also, UR pulleys and others have been on the market longer than g35s and theres products for all different cars. If it was soo unsafe, why are dealerships carrying them and installing them?

 

I could be wrong, but I thought with a SC you couldn't use a light weight pulley? I've read post saying to switch back to your stock pulley if you go SC due to losing power and possible problems.

 

*cough*

 

So sitting in my car idling w/ no radio on/ I noticed my "noise" got considerably louder when I turned on the A/C. So now I'm definitely thinking it's just loose belts/ or worse the A/C pump-- which is warranty (I think) so I think I'm good.

Now got to go pay for my $30k check up..
Gonna be an expensive trip:

- 30k check up
- clean my MAF
- oil change
- tighten my belts
- Fix the A/C noise

Oh well- gots to be done.

PS- I agree with Jeff now and totally agree the pulley issue was likely due to a bad install -- and perhaps even a rough "uninstall" as to me it appears as that was when the pulley was damaged.. and maybe the crank too IMHO

 

I don't specifically recall the dimples around the edge, and I don't have a pic of the same side that's pictured, but this is a pic of the new (unused) UR CP I sold on here a good while back. Wish I had a pic of the other side, but these two certainly have some similarities. FWIW, this anodized-blue UR CP was from the first run, as UR stopped anodizing them just as I was buying mine. I wanted black, but Performance Nissan explained UR's change (and no black in stock), so I opted for a blue one they still had in stock.

I'm certainly feeling better about not having installed it. And I was just regretting it a bit no more than a month ago.


Here's a pic to compare:

 

I think you'd have to be a damn fool to put a pulley on wrong seeing that it can only go on one way My vote is still for lack of a steel key slot. When the crack bolt is torqued down to it's 135 ft/lb spec, it places crapload of stress on the face on the pulley. Seeing that alumninum is rather brittle, it may crack. The reason the timing went to hell is because the pulley most likley wobbled a bit after was broken. The reason the crank bearings went to crap is because the crank became wildly unbalanced.

The lack of a steel key slot is a major issue, IMO. Aluminum wears, especially under friction. Years ago other aftermarket companies offered crank pullies for the VQ30 without steel key lots and they found out the hard way that it's needed because the pulley will wear out and will wobble.

 

There are lots of expensive and damaging products on the market. Many of which don't show a gain like the lightened pullies.

My opinion of UR is that they're clueless about the design nature of nearly every late model OEM crank pulley on market. You can be damned sure that if your UR pulley fails and takes your crank bearings with it, they're not going to help you out. They'll only replace the pulley.

 

Dave. The pulley can only go on one way. That is true. But it doesn't prevent the pulley from being installed incorrectly. If the key doesn't stay in the crank's slot, it will poke though the back of the pulley/crank slot. Thus causing the damage you see in the picture. Note you don't see the pulley being damaged further down the pulley slot where the key is SUPPOSED to ride. Only on the inside edge.

 

More proof:

In bold, that is the EXACT setup the VQ runs.

http://www.gmpartsdirect.com/perform...CATID=895.html

Here is the OEM crank damper used in the GM's LT4. Take note of the tiny elastomer ring and how similiar this pulley is to the VQ pulley.

http://www.gmpartsdirect.com/perform...CATID=895.html

 

How well balanced are the LT4s vs Nissan's VQ series?

 

The LT1/4 aren't remotely as structurally sound as the VQ, but the V8 nature of the engine does help in terms of the torsional vibrations. With that said, my point was that the thin (slightly more than 1/8") elastomer ring is indeed a damper. Like on the LT1/4 crank pulley, the elastomer on the VQ pulley is sandwiched inbetween two pullies. Taken straight from GM, it proves that the tiny elastomer ring is a damper and is not there to quiet accessories.

I've said it many times, the lightened undampened pullies probably won't damage the VQ in the short term (sub 150K miles), but the dynos and track numbers plus the physics of a crank pulley show that there aren't gains. If it was my money, I'd suggest buying something else. I was once a sucker and bought one of these pullies for my old VQ. It did nothing, but but make for a quicker revving engine when in neutral and increased vibration. No gains.

 

Dave, we will agree to disagree. I felt gains with my udp in my maxima. It indeed reved quicker in gear than before. Now that might not show up on a dyno as you don't dyno in the lower gears that you feel a diff in. I noticed no additional vibrations.

To me, anything to get the auto 03 sedan out of the sub-3,000 rpm range asap, the better.