belt for 15% pulleys

[holdenontoit]

Hi folks.I don't spend alot of time here, but i do check in from time to time.I just had some service done on "Zane Grey", including the replacement of my supercharger belt (at 45k miles,probably looong overdue).
I had a conversation with the service manager Gary, at MINI of Peabody(MA) about whether or not the JCW package included a slightly smaller belt for the 14.8% reduction pulley, and he said that it does.Having had a 15% pulley since last summer (a la Randy Webb) I told him I wanted THAT belt installed.He explained that he could not replace it under warrentee because I didn't have a "registered " JCW package,but that he HIGHLY recommended it for people with reduction pulleys, so I thought to post the part # for all you happy campers:
part # 1 11-28-0-300-802 jcw ribbed Belt. Peace, Jock

PS I am renting a tool which captures the OEM pulley to remove it,identical to the bavarianmotorsports tool.
for details email me at jnhholden@comcast.net paypal accepted.

[obehave]

Thanks

[UnderRadar]

Great to know. I was curious as to whether a smaller belt was available for the 15%. I'll feel better having that on.

[bkwalker]

hey im no pro at all this but i got a new belt for my alta 15%..

i think any old belt will do, doesn't have to be a JCW..

i got size 6PK1365mm.. that is what was recommended

[roland2003]

Well they should use a shorter belt .If you dont the tensioner will be much more extended
therefore allowing very little wear/stretch to take place before the tensioner hits the OE
'end stop'. If that stop breaks off because its permanently hitting it (because the belts too long) then the tensioner damper comes down and mashes into the crank pulley/harmonic
damper. If it doesnt break it off then the belt slips losing power & wrecking the belt (or worse) On top of that the excessive 'doubling back ' of the belt which it creates reduces
belt life. Finally to not replace the belt (even for std length) is poor practice. At
£1000-£2000 its the least anyone should expect (IMHO)
Regards Roland Gt Tuning.
JCW are absolutly right in deciding to fit a shorter belt in their conversion.

[LordNikon]

I was told by Ray West that the 15% pulley he put on mine, came with a new belt, I would certainly expect it when working with any reduced pulley installation, no matter what size !

[roland2003]

Hi Max, Yes you do need a belt that is shorter than the original 1388mm MCS belt.
It may well be that whoever fitted your belts has used a shorter aftermarket belt anyway
but not said. The key thing is once fitted and in use that there is around 10mm plus/minus
2mm of 'available travel 'before it hits the end stop. If you use larger idler pulleys as we do'
the actual 'optimum belt length', will be longer,in fact on our conversions, we could use std length belt even on an 18% pulley,but I still dont. The 'apparent' amount of available travel changes on a hot engine so dont be surprised if it looks 3mm different on a fully cold engine. If you pop down sometime to say hello I'll have a look just to make sure.
Regards Roland Gt Tuning

[Mike Edwards]

Dyno Day???

When?

[roland2003]

Thanks Max,yes Ill have a look then. BTW if you can round up a few of 'your boys'
for the Rolling road day that would be splendid. You can have a SCNM promotion there if you like . We may have a few of the new GT Tuning parts on show aswell.
Regards Roland Gt Tuning