Hi guys,

The car has been on the dyno today and made 343wkw (460whp) but they can only get two consistent runs before the belt stretches out or slips with the tension on it. There's a custom tensioning system on there but it's just not holding.

They are very excited as they said the 100% meth mix is working beautifully and there's still a large tuning margin left. I' running a 3.6" pulley and a 6.5" crank pulley with a gatorback belt, I thought this would have sorted all my issues out but no

I've done a large amount of research and I know some people have done the 7 rib conversion or even a toothed conversion but this sounds like some serious fabrication work unless there's a kit ready to go off the shelf?

Does anyone have any other suggestions?

 

Revert back to the stock tensioner?? Either you're not torqued down nearly enough, or that custom tensioning system is worse than the stock one. Most people on the stock tensioner only run into problems down in the 3.2" and smaller sizes. I run a 3.4" pulley and have no issues with belt slip (above 1st gear). Also, make sure you are using the largest belt you can, and still achieve maximum tension in order to ensure maximum belt wrap and traction. Alternatively, you could take a dremel to your supercharger pulley and cut horizontal notches into it.

Or you could just put some Harambe glue on it

 

This scenario is exactly why I stayed with 3.4 pulley and realized I just need to buy a vette,gtr, etc

 

Larger pulleys and 8 ribs will solve the problem. In my case, boost went from 19psi to 26psi with no further slip.

 

I know several have added an idler pulley opposite of the tensioner pulley to give more belt wrap, that would increase the amount of wrap the belt has on the blower pulley and eliminate most belt slip. I know s2k manic has done this, maybe he'll post up details on his setup.

 

I think the belt isn't tight enough, and the new tensioner you have isn't as effective as the stock on. I suggest putting back on the stock tensioner and tightening the belt more. My pulley is rated for 14psi, I was constantly only seeing 11/12psi. Tightened the belt a turn in a half, two turns, then began seeing 14/14.2 psi

 

Hi,

Thanks for the ideas, suggestions and comments!

I've told them to slot the blower pulley and i've also supplied them with a larger belt. I'll float the idea of another tensioner pulley too.

As for the tensioner they've fabricated there is no way it's worse than the CT one, that one is awful.. It wasn't just failing to tension at all but the bracket was sliding along its guides. This is the one they created which modified the CT one;



I need to clarify whether it's slipping or the belt is stretching due to the tension or both as they weren't clear about that. I remember when i kept tensioning my old gatorback with my 2.8" pulley it eventually snapped.

 

my pulley setup

 

Is there any evidence that shows a belt (when new) will stretch and then after "break-in" will settle and re tightening will hold?

 

Hey mate are you 8-rib? If not why didn't you go down than path?