7.4 vs 8.?

wats the difference appart from size, i mean wat the advantage to smaller/bigger disc brakes

you mean 7.5 vs 8.4?

i would have thought it was obvious - bigger diameter = more clamping force

i wouldnt know but apparently 8.4metro disc's are easier to come by than 7.5's? either way buying new ones or fixing up old ones with replacement parts is going to set you back the better part of $1200-$1400. also fitting disc's required you to switch your rear wheel cylinders

http://www.carbibles.com/brake_bible.html <-- this is your friend

Main disc sizes are 7.5 and 8.4".
The performance between the two sizes does not differ a great amount, but verse a disc braked mini with a drum braked one, and the differences are huge.
Drums tend to fade when they have had repeated hard slows (ie hills), whereas discs take longer to get hot and therefore decrease in braking efficiency.
Drums are not self adjusting, by that it means they'll need regular adjustments to keep the pedal feel strong, and therefore keeping braking to a maximum.

The cost of disc brakes are worth every dollar.

That is all.

One advantage of 7.5"s is that if you running 10", 12" or 13" rims you can stick with them

If you buy 8.4"s, you need to factor in the added cost of purchasing new rims amd tyres if you arent running 12"s or 13"s as they wont fit under 10"

_________________
No more Minis!......For now.

If you can find a 7.5 for the same price as 8.4, buy the 7.5's. More versatile with wheel choices. They do run best on 10's

_________________
Lillee - 1969 Morris Mini K

It's quite a good thing to do for safety reasons, to keep "up" with modern cars..

_________________

yeah thats what i was thinking cush... also i was hoping to get 12's or 13's so no drama's there...

why is that ?

Because the discs bite better, there is more weight transfer to the front under hard braking.
Cooper S had smaller rear cylinderss, 5/8" dia instead of 3/4". This gives about 30% less braking at the rear, so they don't lock.
Trust me, it's no fun locking the rears up on the F3 freeway during a panic stop from 120KMH.....

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

aw.. c'mon... not even an itty witty bit of fun?

_________________

Yes I guess it would have been `fun' if I had hit what I was avoiding... NOT.
good thing I'm an old Amaroo Pk dirt circuit man.
I've got 2 S cylinders for Barney now, just gotta fit `em.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

ok cheers for the heads up

I would consider a Honda conversion if it's not too much effort to get engineered in Aus. The Honda conversion I did on my Mini stops so much better than my girlfriend's 8.4inch Mini brakes it's not even funny. And they cost me about 1/3 the price to do, including having the calipers and mounting brackets powdercoated. However with the Honda brakes I chose I did have to buy new wheels and tires to fit over them. But I did need new tires anyway and I sold the wheels I had on the car for about 2/3 the price of the new wheels so it worked out quite well.

_________________
email - [email protected]
http://s28.photobucket.com/albums/c207/TurboOrangie/

67 Traveller - Needs restoration
www.victoria-chiropractors.ca