LSD

Can’t say from first hand experience yet, but given that its based on an E30 and the reviews mentioned the m powered version is a bit twitchy when it is wet I would highly recommend going for an LSD (Limited Slip Differential) – I sourced mine via www.e30zone.co.uk but also try www.planete30.co.uk and www.ebay.co.uk

3.91 ratio will give loads of acceleration but will be less efficient at motorway speed.