G lader pulley sizes.

[Bushpig]

Just interested to see peoples views on how small you can actually go with the pulley?

Most company's seem to go as low as 65 mm and that seems to be the choice of most people , however Dub force tuning offer a 55 mm pulley....

Thoughts on this size ? I would imagine it would half the life of a charger?

Cheers Danny.

[PeteG40]

it puts the  normal countershaft bearings outside their tolerance range.  With a 58mm pulley i've seen melted oil seals and with a 60mm seized countershaft bearings leading to a grenaded charger.

[Bushpig]

Bloody hell catastrophic then!
Well this has cleared this issue up.

Cheers.

[physicsfool]

With a 65mm pulley I have been advised to re do seals and bearings after 15k so I imagine anything less will take the fun out of having a G-lader

[Jezza-7]

I ran a 65mm pulley and did nearly 25k. Had a seal go and was replaced but that did really well.

55mm pulley is far too small unless you have a few chargers spare!

Are european friends tend to run smaller ones though. 62mm rings a bell.

[polo classic]

I did use a 58 mm toothed belt pulley for a while,

Charger rebuilds every 1500 km, too much hassle really

You tend the "burn" the lip of the seals and taper the apex seals

[Justin14100]

I use a 2:1 ratio toothed pulley system, any "65mm toothed pulley" set should be 2x crank speed, standard v belts run at 1.6 crank speed. I think the next pulley down was 2.21x crank speed.

[Ä‘uro]

how many revs charger can take before cracking ? And how can I know rpm on charger based on pulley size ?
is there any calculation ?

Tks
Damjan

[G40supercharged]

If the standard ratio from engine to charger is x1.6 this means the standard V belt engine pulley is 120mm (1.6 x 75mm). Therefore revs at charger = revs at engine x 120 / charger pulley size in mm. 

If the '65mm' toothed pulley set up gives x2.0 this means the toothed engine pulley is slightly different to the standard V belt engine pulley (in this case its the ratio of teeth rather than diameters that matters). Assuming the calculation at the top is correct, V belt pulleys at 65mm would give a ratio of x1.85.