I have a mk indy that was changed from a pinto to a bike engine and want to change the diff to a taller lsd one, I have the diff, shafts and hubs from a xr4x4 to swap on to it but need to get some discs and calipers but looking at sierra rear discs they are bigger than the fronts! Is it possible to use smaller ones like front ka or fiesta ones?

Hi
Stick to drums on the back.
you don't need the power of disc on the rear in such a light car
We have drums & still had to fit a bias valve on the rear.
& so they say drums are lighter than discs.
good luck.

what front hubs / discs have you got ?


the std. sierra rear disc is a 253mm solid one with only a small pad area
the matching front discs on the sierra are 260mm vented (which are a bit OTT for most of our cars and they are a bit heavier too), these use larger calipers with bigger pistons, but the hubs and mountings are all the same


you could use fiesta discs on the back just like some of the drum brake conversion kits, but the mounting lugs on the XR4x4 hub carriers would be in the wrong place so you would need to make up brackets to mount the calipers at the correct position in a similar way to the drum conversion kits
(the bearing sizes are different for the drum and disc brake hubs, so you can't just use the drum brake hub carriers without some work on the lathe)


I'm not sure if the drum brakes will fit on the disc braked hubs - but if you've got all the bits at hand you'll be able to work that one out yourself


its not my favorite but the other option would be to make up hybrid shafts (i.e. bolt on one end and push-in the other) that way you can leave you current brakes setup as is
quite a few people have done this, it works but the shafts can wear out quicker due to the mismismatch of CV joint designs at each end (but most folk don't do enough miles for this to matter)

[Edited on 11/12/2013 by mcerd1]

Thanks for the replies people, not sure what the front brakes are? sierra I would think, there vented but not very big will measure them at the weekend. Have read about the hybrid shafts and would rather use one type of shaft and I have all the hubs and stuff to match just think the sierra rear discs are a bit big and will look silly with bigger rear brakes than the fronts.

Not only silly but dangerous if the rear brakes lock
up before the fronts.

It would be pointless to change over to discs in a car of such light weight. Stick to drums at the back with good quality consumables. Mine are stock and the brake balance is perfect- stops cleanly without any undue locking up.

quote:

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Originally posted by renetom
Not only silly but dangerous if the rear brakes lock
up before the fronts.

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