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Williams Performance are the ONLY place in the UK offering this conversion as a drive in -drive out service.

We supply all the needed parts to carry out this upgrade.

When running big power through your HP50 transmission it may start to 'slip', the HP70 gearbox will hold a much higher torque figure than the HP50 which comes in the M140/M240 etc as standard.

Included in this is a new sump/filter along with fresh transmission fluid.

We carry out this service for £1500, this includes EVERYTHING needed. Drive in with your standard HP50, leave with your upgraded HP70

Please call or email us for more information on this conversion.