ok, i'm shopping at the moment for parts for my new car and REALLY tempted to go down from the Rover 8.4 brake set up to the 7.5 brake set up, allowing me the option of 10 inch wheels should i ever want to go that way.

Now i have not had the pleasure of being able to test these systems side by side or had the pleasure of using the 7.5 brake set up at all, so the question is...

Would i really notice the difference down sizing my brakes? Is there any major reasons not too?!?

I just want the option to be there and whilst im in the process of carrying out a few new car to me jobs thought i might chuck a 7.5 kit in it!!

_________________
New from the UK and wanting a NICE little British car!

With my thorough use of each disc brake size (disregarding the crappy 7" Cooper setup!) I think they are very comparable.
Sure, the 0.9" bigger diameter is always going to be advantageous, but unless you're a brake dragger, you won't notice the difference.

Whack the 7.5s on, pair them up with some hot 10" wheels, and you're onto a winner

Go to 7.5 brake setup for sure, so you can run some 10" wheels

I found 7.9 4pot minisport set pulled up quicker than 8.4 metro turbo, or seemed to. Having said that the 7.5 on the cooper s pull up better than both of them.

_________________
1965 Riley Elf
1974 Ex Army Moke
1997 Rover Cooper
2002 JCW Cooper
2003 JCW Cooper S

Both the 7.5 and the 8.4" will stop the car just as quickly, for the first few applications. The 8.4" brakes have the disadvantages of being heavier and limiting your wheel choice to 12" or bigger. Their advantage is that they can shed heat better and are then less prone to fade.

I have only once managed to get brake fade on my 8.4" brakes once, and that was on a 40C practice day at the end of a 185kph straight. For a road car they are probably overkill.


<edit>

_________________
Too many cars, and too little time.

7.5's also work well. i dont think its worth the cost of conversion, but it does depend on how much you want the 10" look.

I have 8.4" discs and am wishing i had smaller ones so i could fit 10" wheels if i chose to. I won't be changing them, but if i had the choice i'd go for 7.5" simply for the wheel choice reason.

_________________
- Simon -