im after a limited slip diff for an English axle that i can use for drag racing i intend to put about 250hp through it any recomendations

I would look for a stronger axle. In circuit racing an engish axle will cope with that sort of horsepower but I would venture that putting 250 bhp through an english axle on sticky tyres from a drag racing start has great potential for DNFs

Of course it really depends peak torque and gear and axle ratios, a Rover V8 will snap a halfshaft quicker than a 2 litre Silvertop with the same or more power, the pinnion on short ratio final drive is generally weaker than pinion on a longer ratio (because the pinion gear has less teeth) and the effect of gear ratios is obvious.

i think youll need a fully locking locker for drag racing........

why not just weld the diff up if only doing drag racing? the locost way