Jbottini mentioned Kenny Bell – IMO an excellent alternative. Twin screw positive displacement ‘chargers produce substantially more power from zero revs right up the range, whereas a centrifugal blower only starts to work above about 4,000 rpm - useful if your rev limit is 6,500 – 7,000, but the 5.0L is a relatively low revving engine and needs major mods to hold it together much above 5,300. Either way, full potential won’t be achieved unless aftermarket heads are fitted (the exhaust ports are very restrictive on stock heads) together with free flowing inlet manifold. Also, when swapping heads replace head bolts with studs to avoid gasket failure.
I believe the Kenny Bell kit includes bigger injectors and a second pump to cope with fuel demand, and a programmable chip for the ecu plus all the other bit required.
An alternative using a twin screw is to go down the do-it-yourself route and obtain a second-hand Eaton, as used by Jaguar on the XJR – not quite as efficient as a Kenny Bell – but a lot cheaper. (I just happen to have one I might sell!) Get a tweecer to re-programme the ecu to avoid expensive dyno retune and you’re in business!!!
I had intended supercharging my Brooklands Ace, but in the end was forced to conclude there wasn’t enough clearance under the bonnet - damned stiffener in the way.[
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