Author Topic: G lader pulley sizes.  (Read 2521 times)

Offline Bushpig

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G lader pulley sizes.
« on: November 03, 2014, 04:47:47 pm »
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.

Offline PeteG40

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Re: G lader pulley sizes.
« Reply #1 on: November 03, 2014, 06:21:36 pm »
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.

Offline Bushpig

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Re: G lader pulley sizes.
« Reply #2 on: November 03, 2014, 07:00:32 pm »
Bloody hell catastrophic then!
Well this has cleared this issue up.

Cheers.

Offline physicsfool

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Re: G lader pulley sizes.
« Reply #3 on: November 03, 2014, 07:33:58 pm »
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

Offline Jezza-7

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Re: G lader pulley sizes.
« Reply #4 on: November 04, 2014, 07:06:05 pm »
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.

Offline polo classic

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Re: G lader pulley sizes.
« Reply #5 on: November 19, 2014, 08:04:48 am »
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

Offline Justin14100

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Re: G lader pulley sizes.
« Reply #6 on: January 12, 2015, 12:46:33 pm »
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.

Offline Ä‘uro

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Re: G lader pulley sizes.
« Reply #7 on: January 13, 2015, 03:08:47 pm »

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


Offline G40supercharged

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Re: G lader pulley sizes.
« Reply #8 on: January 28, 2015, 08:39:16 am »
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.