15%-17%-19% pulleys!!!

[T-bone S]

correct - there is no pulley/supercharger change on the GP - only larger IC with revised ECU map that also increases rev limit

[herbie hind]

being that 17's and 19's have been known to slip and also break belts due some say to them having less surface area for traction has anyone made a bigger idler pulley to change the angle of attack on the s/c pulley giving it back some traction?

[MINIAC]

Quote: Originally Posted by venox22 (original)

Works Pulley - 57.9mm = 11% reduction

Someone else has measured the Works pulley at 2.21" (56.1mm) ...

North American Motoring - View Single Post - Let's Dispel the Myths!

[venox22]

is that measuring the tips of the vee grooves or not??

[Perm]

Quote: Originally Posted by herbie hind (original)

being that 17's and 19's have been known to slip and also break belts due some say to them having less surface area for traction has anyone made a bigger idler pulley to change the angle of attack on the s/c pulley giving it back some traction?

BBR use a cosworth idler with their 19% reduction pulley. This special idler is designed to allow for the std belt to be used.

Regards

Perm

[roland2003]

Hi Herbie, yes the GTT Idler Pulleys are available in larger diameters to do just that! 'improve the angle of attack' (nicely phrased btw). Also the GTT T/B Idler Pulley is the ONLY one using two bearings to properly support the pulley ,(one either side) to reduce bearing wear & movement / slop . It's also hard anodised alloy so is light weight yet resists wear very effectivly.
Check our website below for more info.
Best Regards Roland GT Tuning .

[venox22]

so would you reccommend doing the idler pulley and the tensioner pulley at the same time??

[roland2003]

Hi Vennox, yes idealy as both run on the back face of the drivebelt. The Idler does take alot more load though ,hence why its available from us as a Twin Bearing Upgrade Pulley.
Best Regards Roland GT Tuning

[venox22]

Thanks Roland, thats cleared it up for me!!

So your GTT idler pulley uses a twin bearing design as it carrys more load.

And your GTT Tensioner pulley uses a single bearing design as it doesnt carry as much load as the Idler pulley

[herbie hind]

Quote: Originally Posted by Perm (original)

BBR use a cosworth idler with their 19% reduction pulley. This special idler is designed to allow for the std belt to be used.

Regards

Perm

that's cool must be bigger so traction would def. be restored

[herbie hind]

Quote: Originally Posted by roland2003 (original)

Hi Herbie, yes the GTT Idler Pulleys are available in larger diameters to do just that! 'improve the angle of attack' (nicely phrased btw). Also the GTT T/B Idler Pulley is the ONLY one using two bearings to properly support the pulley ,(one either side) to reduce bearing wear & movement / slop . It's also hard anodised alloy so is light weight yet resists wear very effectivly.
Check our website below for more info.
Best Regards Roland GT Tuning .

wow i'm waaaaaay behind the curve on this one . sounds wicked ******a .

[PeteMike]

Not sure if this was answered in this thread but and suggestions to pulley manufacturers? I am looking for a 15% reduction for an 05 stock cooper s.

[DaFlake]

KMT, Alta, Mini Madness etc....

KMT seems to be the choice over there but any will do.

[PeteMike]

Still looking for a pulley here. Anyone know where to find good deals on pulleys that ship to Cyprus?
Also, do I need to change the belt if I get a 15%?

[Keano]

Quote: Originally Posted by PeteMike (original)

Still looking for a pulley here. Anyone know where to find good deals on pulleys that ship to Cyprus?
Also, do I need to change the belt if I get a 15%?

yes you will need a shorter belt. i have a black 16% pulley for sale if your interested? PM me if interested