Ke70 Brakes On Ke20 Struts

[GJM85]

Having issues fitting ke70 calipers and rotors onto the ke20 struts.

 

I've got ke20 struts and wheel bearings, redrilled ke70 dust covers, ke70 hubs, rotors and calipers. The issue at hand comes down to clearances.

Firstly. There is about 2mm clearance between the rotor and raised section of the dust cover. I believe this raised area is designed to clear the control arm. This seems to close to comfort.

The other issue is the caliper won't fit between the rotor the dust cover when I attempt to mount the caliper.

 

Does anyone know how to get our these problems?

[styler]

the dust covers do run close to the disc from factory as far as i know, a lot of people remove the

dust covers anyway by untacking the spot welds using hole punch/dremel/spot weld remover...

[GJM85]

OK. Removin the dust cover will fix one problem. The other is how to I fit the caliper between the backing plat and the rotor? Cutting the caliper mount section of the backing plate and rewelding an offset section to bring the caliper inwards? Have considered a spacer between the inner bearing and the sub axle to bring the hub outwards, but seems a little risky...

[7FOUR7]

whatever you do work out, please post up :)

[coln72]

Weird, when we did that conversion years ago, we had no such issues. What bearings are you using? From memory, had to run the ke 70 outer and the ke20 inner bearings (or the other way around, was over 10 years ago.... :blush: ).

[LukeAE71]

What backing plate are you using??

 

There may be a reason why everywhere I read it says to use KE30 backing plates

[Mick E]

according to peter robinson if my memory is correct. bolt ke-70 discs to ke-20 hubs,keep same stud pattern.redrill and tap struts to take ke-70 backing plates should work cheers mick

[Mick E]

according to peter robinson if my memory is correct. bolt ke-70 discs to ke-20 hubs,keep same stud pattern.redrill and tap struts to take ke-70 backing plates should work cheers mick

[7FOUR7]

What backing plate are you using??

 

There may be a reason why everywhere I read it says to use KE30 backing plates

So ke70 disks, hubs and calipers and ke30 backing plates should all bolt together?

 

Also are ke70 brakes much better than ke30? I have ke30 brakes on my 20 atm

Edited December 1, 2010 by 7FOUR7

[GJM85]

according to peter robinson if my memory is correct. bolt ke-70 discs to ke-20 hubs,keep same stud pattern.redrill and tap struts to take ke-70 backing plates should work cheers mick

 

I think the main problem is the inner bearing, which is a ke20 sits a few millimeters further into the back off the 70 rotor than it does in the 20. Also the 20 calipers are a lot smaller. I'm using the 70 hubs becuase I need the PCD.

[styler]

the ke55 backing plate provides the transition piece for the conversion as the ke55/70 girlock calipers to mount to the backing plate and the backing plate

mounts to the ke20 stub axle flange to hold the calipers in the correct position for ke55/70 rotors which can be mounted to either type of hub in the conversion

- either a 110x4mm ke20 hub or 114.3x4mm ke55 hub, not sure on ke70 hub.

 

the hubs are the same in form and dimensions and rotor mounting, the pcd and inner bearing ID are different,

but since both bearings actually are fitted to the hubs by the same OD however, the inner bearing can be changed to a ke20 one,

as the ke20 smaller stub axle requires a smaller ID bearing to fit and run on it properly.

 

that mounts the components to the correct position and bolting pattern to be held in the same position as factory.

 

the bolting size ie, fastening system is where it is a problem

 

the fastening is M8 on the stub axle flange and M10 on the backing plate,

 

its possible to drill and tap the M8 stub axle flange to a bigger M10 stub axle flange size and bolt the bracket up using M10 fasteners,

however the stub axle flange is quite thin and small in the casting, approx 8mm and so if you drill and tap it you will not get the minimium

thread engagement of even basic mild steel which is specified as 1 times the diameter of the fastener and the surround of the threaded hole is reduced,

the stub axle is actually cast so its probably weaker than mild steel grades as well, this wont pass engineering standards

 

if you use M8 fasteners on the upgrade they have the correct minimum engagement and you don't have to drill and tap the stub axle flange but they

are undersized fasteners as the bigger brakes which come with M10 fasteners from factory, also you would have to reduce the hole size in the ke55

backing plates from M10 to M8 by welding and redrilling or its possible to use an adapter bush but it would be too thin and weak being

8mm x 10mm x 4mm (ID x OD X THICKNESS) or a machined, heat treated and tested hi tensile shouldered fastener with a step below the head as an

integrated adapter but none of these methods will pass engineering standards

 

in my opinion the stub axle flange of the ke20 is just too small and thin to host big brakes,

even though the backing plate actually locates on the the stub axle spigot for a significant increase in strength,

M8 is too small a fastener for the bigger brake loading,

M10 does not have sufficient engagement to the stub axle flange,

 

some big brake companies advertise bolt on upgrades for the ke20 with something like 300mm rotors and

4 pot discs but the increased loading on the small bearings and stub axle flange leverage from 300mm

discs wouldn't probably wouldn't pass engineering standards

 

its possible to convert to a bigger stub axle by using bigger stuts

which the come with their own world of issues on mounting and various geometry problems,

 

these are only my observations of the conversion having actually done the conversion myself but not used it,

it's possible that some people run a version of this setup i really don't know,

NCOP (national code of practice) has a section on brake upgrades

Edited December 10, 2010 by styler

[7FOUR7]

Very informative reply, cheers mate! I'll stick to my ke30 setup until I go the r31 coilovers in the future

[GJM85]

 

I now have a much better understanding of what i'm in for. I also now wish i had uses the ke70 struts and had the shortened. Southside Suspenion shortened my ke20 struts anyhow to get the low I requested. Win some lose some.

 

I'll make this work.

 

I'll look into re-enforcing the axle flange. This will allow me to offset the caliper from the mounting bracket.... maybe.

[GJM85]

Family and beer around a ke70 hub and rotor.

Solution found...

...separate the rotor from the hub. Machine the out face of the rotor 3mm, where the hub bolts on, bringing the rotor outward 3mm to enable clearance between the dust cover and centering in the caliper.

Edited December 3, 2010 by GJM85

[7FOUR7]

sweet! Any chance you could throw up some pics for reference?