Prior broken pulley bolts were the center bolt that goes into the blower directly. This was isolated by KW to a limited set of blowers due to a probable installation error of the hub by KW. Only one person had a recurring issue here, and he is in Argentina and wasn't sending the blower back for repair, which is a likely component of his repeated failures.

Broken VTEC solenoid bolts were isolated to installs that weren't properly & evenly torqued. Everyone that had broken bolts stopped having the problem after using a torque wrench to evenly tighten them. Also worth noting other kits in the past have had failures here.

This issue has never been seen before, with the 6 pulley to hub bolts breaking. OP acknowledges there could be an issue with too tight belt tension, and also never replied about them having been torqued & loc-tited properly.

Are there any other repeat failures out there that don't fall into one of the above? All this talk about how the mounts aren't sufficient etc etc yet I just don't see the evidence for it. My 5k miles, LBPS2k's 6k+ miles, and one of LHT Performance's customers who is approaching 20k miles (including track duty) are pretty good indicators the kit can be reliable if installed properly.

 

It is a bad design, especially for the s2k's motor due to its high reving nature. The primary gear reduction of centrifugal supercharges are extremely high, imagine 10 to 1. That means when you rev your motor from 1000 to 9000 rpm in 2 seconds, the super charger has to rev from 10,000 to 90,000 rpm in the same time frame. This puts an extreme amount for stress on the components since the belt is cogged and can not slip. That is exactly the reason most centrifugal superchargers do not use cogged belts. When the belt slips it is actually protecting the components including the primary reduction gears/ pulleys, ect.

 

I guarentee that a lot of these problems are from belts being too tight also .. Mine is really loose compared to serp belt .. Haven't had a problem in a while thank god and had some good track days .. If the clogged belt is a problem..i also have not hit red line .. They should give us new pulleys and regular belts .. They put a cogged belt and the only reason I can understand is to stop slipping .. But every one says the slipping is good .. So why .. I want kw to do a test and just redline the piss out of a s2k with their kit and see what happens ..

 

FWIW I've bounced off of my "soft" AEM rev limiter dozens to hundreds of times by now. I don't do it intentionally, but it does happen sometimes. I stopped puckering over it months ago.

 

There is a difference between excessive belt slip/boost loss, and just enough slip under high duress to save the components. KW decided (I imagine) that they would use some marketing ploy to "cure" belt slip by moving to a cogged system, where it was never really a issue to begin with, just from people that didn't know how to properly tighten a supercharger belt (I ran a 3.2"/5.45" NV1200 with no slip issue and a 2.7"/5.45" NV1000 with no slippage issue) So now its proving to be a problem of poor design/move in KW's case. The Rotrex blowers use a more involved planetary gear drive which spins at twice the speed as a typical Paxton blower 50k rpm vs 100k, and I would imagine provides more parasitic resistance/load as well. Couple that with the high rpm character of the engine its mated to as was described by alloywcraft, and you have a recipe for poor reliability/longevity when you tell it to have 100% no slip from a cogged belt. I pointed out my great suspicion to the cogged system on this kit when it first came out, and its proving itself to be the case more and more as time goes by.

I hate to say this, but stay tuned for the next related cogged belt failure...

 

well what's the difference between soft and the regular rev limiter .. I don't know how mine is set up ..and difference in strain on the parts ?

 

I thought i had mention that, but yes i applied blue locktite and even tightened them (star pattern) with 8 lbs (using a torque wrench). Im also considering that even if one bolt snapped on its own, the chances of the other snapping while spinning are very likely

 

I'd have to be sitting in front of the software to find it exactly, but I think in the wizards there is a rev limit setup, and there are default %'s for how aggressively the ECU cuts fuel/ignition at the rev limiter. A hard cut is a very distinct & abrupt event, where on the milder settings it bounces much more gently. Jeff Evans set mine up this way by default. I don't know if that's just what he always uses, or if it was a conscious decision based on the KW kit.

 

Got it, thank you for following up. How tight would you say you had the belt? How much deflection or twist could you get on it, and at what location?