Hi Graham,

Long time no speak! Alas, black manta is no more, it went to the (very full) manta graveyard a while back! Come on over sometime and have a gander, it'd be good to catch up!

Back to the Manta, I've been concerned that the 7.5" diff will be too weak with the power I'm running, especially with the diff being solidly mounted, the clutch being very on/off and also being unsprung, the engine bring reasonably solidly mounted (well, it will be when it's done), and the rear tyres being huge! I've done some reading about this on passion ford, and they tend to upgrade at the 400bhp level. The upgrade paths are the ford 9" diff (hugely expensive), and the Jag back end (hugely heavy).

I just had a good chat with Stuart at Gearboxman (www.gearboxman.com) about the strength of 7.5" diffs. Apparantly the main weakness of the 7.5" diffs are the planet gears on the diff. This can be solved with a decent LSD Unit. Rnd make a good (but expensive at £1250+vat) unit, and the Quaife ATB comes in at 750ish.

Stuart also made a very good suggestion of using rubber dognuts in the propshaft to absorb the driveline spikes when changing gear. this'll protect both the diff and the gearbox, so I'm going to do some research on this. Having had this chat, I think I'm going to stick with the 7.5" diff.

When I put it all together on the sunday, I was worried about the driveshaft angles with the axle at the desired ride height. The easy fix for it will be to raise the diff up slightly. this won't be that hard to do at the moment. it'll probably take a day to rejig it all.

I'll have another look at it and take some photos of it tonight.

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