Hello everyone,

I am new here. I have a Kraftwerks Charger kit on my car. The stud(one of 3 bolts) that helps hold the supercharger with bracket to the motor has broken off. I have received all the parts from that failed from Kraftwerks and they have been great. I could not ask for better customer service. I was going to replace the stud with a bolt of a higher grade bolt so that failure doesn't happen again but its almost impossible to be able to install a bolt as it has to go through supercharger bracket, then the a charger pulley, then a spacer from the kit, then a factory washer/spacer and finally through the idler pulley into the motor. Can i just remove the idler pulley and route the stock factory belt another way with out using the idler pulley?

 

Did you make sure you loosened the tensioner pulley all the way loose? I had a tough time threading the top mounting bolts until I realized I should've loosened the tensioner pulley bolt and slid it all the way loose to install the bolts.

 

I am not talking about the supercharger belt or pulley. I am talking about the stock factory idler pulley.

this is broken stud that goes through the stock idler pulley and through the kraftwerks charger pulley.

Here are both pulleys that the broken stud went through

the broken stud in motor

broken stud and kraftwerks spacer

 

Why are you insistent on a bolt? Just use a stud of same strength as whatever bolt you wish could fit.

This topic, and what grade of stud to use, thread size needed, etc, has been discussed. Just do some searching.

 

I think you're going to have to tap that bolt out man. Are you saying the stud is too short to fit both the stock idler pulley and KW pulley?

 

Ok, just so that everyone one is clear here. The kit has worked, I have 700miles on when the stud from the kit broke. I have removed the broken stud, I am looking at different ways to run the belt so that i do not have to use the factory IDLER PULLEY, this has nothing to do with belt tensioner pulley which is reverse thread. The reason i started this thread was to see if anyone else has experience this stud breaking. Its been on post over the internet. I was looking for some help to solve this problem so that it doesn't break the stud again. This is why i wanted to use a bolt instead of stud because it may be to much load on stud as there are only 3 x M10 bolts holding the weight of charger kit with pulleys.

when it was finished the install of the kit

Corner balance

Ride height set and corner balance completed


this is way i have routed the belt now.

This is factory way of routing the belt with IDLER pulley which is just above the crank pulley

 

ARP AM4.600-1LB stud. You'll also need an M10x1.5 nut for that stud as the thread pitch is different on either end. I'd urge you to look into the Ballade pulley kit when you do this again. That stud snapping within 700 miles is not normal, and even KW themselves are re-designing the drive system on this kit. The cogged belt is just too harsh of a drive system for the mounting components and the supercharger itself. It seems at this point either that stud snaps, or the pulley bolt on the head unit breaks.....and those are high-grade hardware. Be aware, there's reports of the ARP stud snapping as well. There's no way to make this kit run reliably; it's been out for years and the same issues still persist. Take my warnings with a grain of salt; I personally had a brand new KW kit that I was going to install on my car, and instead opted to sell it and run the TTS kit. Much nicer kit, and I'm not expecting any problems.

 

Hi Kyle,

Thank you for your help and information. I will consider another kit but sucks cause I have spent all that money to buy another kit...Wished there was better way to secure charger bracket to the motor. Please keep me posted your TTS kit.

Mark

 

No need to buy another kit sir. Ballade has this pulley setup that converts the cog belt to a ribbed belt; reports so far have been good. I can definitely say it is much less strain on the kit as the ribbed belt has some give to it.

https://balladesports.com/products/b...bbed-belt-conv

Just something to consider. It sucks having this kit fail and having to fix it & spend more money; luckily Ballade has come up with a solution that saves you from having to buy an entirely new kit. But give it another shot with the ARP stud and the belt a little looser and report back. The KW kit is really weird....I've seen people do the most meticulous installs and have issues immediately, whereas others have been running fine for years. No one has seemed to find the perfect point where this kit is happy and reliable.

 

The diagram of your new serp belt routing has very little belt wrap around the alternator, and not a lot on ac compressor.

The alternator is a small pulley, so total belt surface area is now tiny. I'd be concerned it'll slip. The ac compressor is larger pulley, but also high load. So hopefully still enough belt wrap to work.

Total pulley surface contact is what makes belt transfer power without slip. Things that increase surface contact; larger pully, wider belt, more belt wrap.

By far, belt wrap has largest impact on surface contact. Wider belt adds about 3.5mm x length of wrap surface contact. Larger pulley is just an inefficient way to get more wrap length. Increasing wrap adds (6x3.5)mm x wrap length change. So you can see why wrap is so important.

Speaking of belt wrap, when kw built their cogged kit, they didn't have to rely on wrap to achieve power transfer (the cogs do that). Hence not a lot of wrap around sc pulley in their design.

So simply converting the existing design to a ribbed belt, as Ballade as done, doesn't provide much belt wrap. They've gone to an 8 rib belt to try and compensate. Time will tell if its enough to prevent slip with a manual tensioning. Finding a tension that will work cold and hot, prevent slip yet not stress pulley and sc bearings, will continue to be a challenge.

If you want to see what good belt wrap looks like, check out the belt routing of the TTS kit. They paid attention when they designed their kit.

I'm currently working on a ribbed belt kw conversion that uses a 7 rib belt, an auto tensioner!, maximizes belt wrap, and greatly improves kw bracket mounting. The goal is to rival what TTS kit provides in solid bracket mounting and proper auto tensioned ribbed belt with maximized wrap, yet in an easy and economical conversion for kw owners.