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PeterW
08-04-2012, 08:59 PM
Hoping somebody can help with a question. I've got a TB/WP service coming up, and will replace the crank pulley. But I'm thinking about installing one of the shields which I've seen mentioned here and on NSX Prime.

As far as I can see there are two suppliers, Titanium Dave on Prime and Science of Speed. Does anybody have any experience or recommendations which one to go for? Or maybe there are other suppliers?

Sorry if this has been discussed before, but I couldn't find anything.

Peter

nobby
08-04-2012, 09:07 PM
think i got mine from TD on Prime ... no issues for me :)

NSXGB
09-04-2012, 04:26 AM
Pete, I believe TD makes them for SOS.



Hoping somebody can help with a question. I've got a TB/WP service coming up, and will replace the crank pulley. But I'm thinking about installing one of the shields which I've seen mentioned here and on NSX Prime.

As far as I can see there are two suppliers, Titanium Dave on Prime and Science of Speed. Does anybody have any experience or recommendations which one to go for? Or maybe there are other suppliers?

Sorry if this has been discussed before, but I couldn't find anything.

Peter

Kaz-kzukNA1
09-04-2012, 09:15 AM
Hi, Peter.

As NSXGB mentioned, it seems that SoS one is from titaniumdave and they seemed to offer just the light weight version. There is a heavy duty one as well.

While it seemed to be quite popular at NSX Prime and I saw this shield installed on a few NSX in UK, I have never seen or heard about it being installed on the NSX in Japan.
The owners just simply replace the crank pulley regularly depending on the usage of their NSX and that’s the recommendation from the NSX specialists.

For every day street driving condition, replacing it at the time of every TB service is enough.


I wrote the same thing below long time ago when I was asked from one owner.


While it looked to be very good product and it will protect the TB from being chewed in by the dislocated pulley weight, it doesn’t seem to mention about the main purpose of the crank pulley on our NSX.
There are some aftermarket crank pulleys available but these don't seem to be tested against the following point.


While for most of the production cars, the pulley counter weight is acting mainly for the damping purpose to cope with the sudden reverse torque/changes in the load by the aux units such as A/C compressor, etc, it is different for our NSX.


While it still acts as the damper, the main purpose of the pulley weight is to shift the resonance frequency out of the usable rpm range to protect the TB itself.

I heard from my friend that during the development stage at the engine dyno, the engineers found that at a certain rpm, there was a resonance frequency that could significantly shorten the life span of TB.

Under the normal street driving condition, it is very unlikely to stay at a specific rpm for a long period but nonetheless, it can’t be left without any countermeasures as a production car manufacture. Hence, such a heavy crank pulley.

So, even with this shield, I don’t know what is happening to the TB if the engine was kept running with the dislocated weight.

It will be the decision of each owners and for me, I have never used it on my NSX and kept replacing the crank pulley regularly.
I never had any problem over 17-18yrs or 135K miles.

Kaz

Sudesh
09-04-2012, 09:17 AM
Personally I dont think its needed as the pulley should be replaced at correct intervals, long before it gives up.

Hagasan
09-04-2012, 09:47 AM
I think the intention of the part is just as a last resort should the worse happen and the balancer fails. True if the HB is replaced regularly then the shields design intention should never be called upon but I can see why some people might like one for peace of mind. That's not to say that if you were unlucky an HB couldn't fail earlier than expected. No part is immune from failure. I recently bought a part from a UK Honda dealer brand new. The first part did not work at all and the replacement did not work correctly. Third time lucky as they say....

With the hap-hazard servicing of some cars, fitting this part may save the owner or "NSX-unaware" newcomer the unfortunate result of failure such as that encountered by a member recently. Some owners may in future simply not believe there is a need to replace the HB if their mileage is low. The shield may save them.....

I personally don't have one fitted but I don't see the harm in fitting one as long as you still check your HB from time to time to make sure it isn't broken and just spinning against the shield. As I have no experience of a failed HB, it may be that you would hear it once it has failed anyway but at least that would be before it chewed it's way through the belt covers and worse...