I understand that a 3.62 ratio is good for my Indy-Blade. But what if a 3.92 is fitted, by how much will the 0-60 be improved and what loss of top end will there be. Consequently what if a 3.38 is fitted, will the 0-60 be unacceptable but what sort top speed. Also must it a 7"diff?
Regards
Barry

With a 3.92 diff fitted to a blade and average size 15" tyres your top speed will only be around 110mph,with a 3.38 this would be around 130mph the 3.62 would be around 120mph.
As for the diff size if your MK chassis,I don't no if you have started building your car yet or if you are at the planning stage,but if your chassis has not yet been built then you can fit a 71/2 inch diff,you just need to specify this when you order it,otherwise your diff brackets will need to be altered to except a larger diff.

I did not specify the size of diff carrier so imagine I need a 7" diff.

Yep 7" diff. The 3.62 also comes with LSD as standard in XR4x4's

Phil

a 3.92 would give 8.28% better acceleration in each gear (neglecting aerodynamics and things) but would have a top speed 8.28% lower. 0 to X MPH would on avearge be the same, depending on whether speed X was just before or just after a gearchange.

Whilst a 3.92 would perhaps be better on a sprint course with speeds upto 100 MPH, a 3.62 or 3.38 would be better for road use because they are less revvy at speed. If you have no intention of cruising the A roads or going on long circuits then a 3.92 might be OK

I posted a recent thread on here regarding my Luego Velocity kit and my 3.92 diff...

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Yamaha Fazer 1000 engine'n'gearbox (similar to the R1 in most respects)

Absolutely CRAZY (and I do mean CRAAAAZZEEEE) acceleration but top speed of no more than 105mph on 15 inch wheels.

When I say CRAZY I mean I slowed down to let Scoobies, Lancers etc. past on the straights (my first outing in the car and I had brake issues) but put my foot down and was on their arse within a couple of seconds.

If anyone's interested I'll be selling my 3.92 differential very soon. It's immaculate and has done extremely limited mileage since an overhaul.

Regards

Kyle, Leeds

[Edited on 20/2/07 by The Great Fandango]