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disc brake conv question

Posted: Sun Jan 16, 2011 11:45 am
by J_Dub
right im doing the rear disc brake conversion on my 85 lux..
snr adaptors, prado rotors mr2 calipers

ive been told that i need to keep the backing plate from the drum setup in place, just cut it down, as its part of the bearing retainer, some other threads and links say this also, but ive stripped everything and have seperated this backing plate away from the main 4 bolt flange and cant see why i need to keep any of this backing plate at all... all this is, was to hold and house the drum brake componants....
Image

have I got my wires crossed or what? but a thread i was reffered to clearly showed this backing plate being cut down...

(to those who i pmed.. no offence or doubt, just want to be a 100%)

this thread shows the backing plate being cut down
http://www.offroadexpress.co.nz/Forums/ ... =18&t=2008

J

Re: disc brake conv question

Posted: Sun Jan 16, 2011 12:17 pm
by rokhound
I just removed it. If it was mounted as sandwich set up between the bearing retainer and axle housing it might be a different story, but it isn't so it can't affect anything if you remove it completely (apart from the fact that the bolts go through further, which you need any way to mount the disc bracket :P )

Oh and bloody good thread link back. That goes back to a time when this site was really worth it's weight :roll: :wink:

Re: disc brake conv question

Posted: Sun Jan 16, 2011 12:41 pm
by J_Dub
yeap thats what i thought, couldnt see any reason to leave any of it in place, but thought maybe it was sandwichd up against the retainer and just couldnt see it though all the dirt and crap..

Re: disc brake conv question

Posted: Sun Jan 16, 2011 12:49 pm
by pruggerdore
dont need it.

Re: disc brake conv question

Posted: Sun Jan 16, 2011 3:17 pm
by Smurf
Seeing it like that, it doesn't really serve a purpose.
I assumed it was part of what holds the rubber seal on the axle in place,

Re: disc brake conv question

Posted: Mon Jan 24, 2011 7:24 pm
by J_Dub
ive got the lj78, early 90s prado rotors as stated by SNR, but the centre hole diameter is 10mm bigger than the sleeve on my hub...

should this be a tight fit as normal???
im thinking that it should be otherwise if it aint dead center i could get a bit of vibration???
or will the minamal amount of slop between the studs be ok and centre itself???

Re: disc brake conv question

Posted: Mon Jan 24, 2011 8:28 pm
by meatc
Just make sure the brackets are designed to have it removed. The brackets bolt on the same side as the backing plate so it may have to be there, or it may not want to be there at all. getting it wrong could mess up the caliper alignment. I'd check with SNR.

Easyist way to get them off is a plasma cutter.

When I did my rears I was worried about the centre hole thing too. I put them on, used the wheel nuts to centre it and then drilled 2 holes (opposite), tapped the axle flange and used 2 countersunk cap screws to hold them. Only need to be little as once the wheels on they shouldn't move, but like you was worried about keeping them centred until wheel was on.

Re: disc brake conv question

Posted: Mon Jan 24, 2011 9:01 pm
by J_Dub
meatc wrote:Just make sure the brackets are designed to have it removed. The brackets bolt on the same side as the backing plate so it may have to be there, or it may not want to be there at all. getting it wrong could mess up the caliper alignment. I'd check with SNR.

Easyist way to get them off is a plasma cutter.

When I did my rears I was worried about the centre hole thing too. I put them on, used the wheel nuts to centre it and then drilled 2 holes (opposite), tapped the axle flange and used 2 countersunk cap screws to hold them. Only need to be little as once the wheels on they shouldn't move, but like you was worried about keeping them centred until wheel was on.



well i bloody hope the backing plates arent supposed to be there cause they are now completelty cut off, they serve no purpose at all now, apart from how you said if the brackets were designed to have that portion of the backing plate there...
oh well itll mean adding a few mm or taking a few mm off the packers for the calipers..
do you think you would notice any vibration if the rotors werent dead centre? im talking like 1mm play as it is now...

Re: disc brake conv question

Posted: Mon Jan 24, 2011 9:12 pm
by haydgq
J_Dub wrote:ive got the lj78, early 90s prado rotors as stated by SNR, but the centre hole diameter is 10mm bigger than the sleeve on my hub...

should this be a tight fit as normal???
im thinking that it should be otherwise if it aint dead center i could get a bit of vibration???
or will the minamal amount of slop between the studs be ok and centre itself???


My Lux uses a 130 surf rear diff and the lj78 Prado rotors fit and locate perfectly and i also fully cut the drum backing plate off as its not needed.

Re: disc brake conv question

Posted: Mon Jan 24, 2011 9:56 pm
by J_Dub
130 and 60 surf centre sleeve must be different, i could see if i can find a perfect match rotor or do what meatc done with keeper screw or get a 5 mm ring turned to close the gap..

Re: disc brake conv question

Posted: Tue Jan 25, 2011 5:13 pm
by J_Dub
well ####, calipers turned up today and got my hands on some high tensile bolts ready to install everything to realise the caliper bracket can only be fitted with the bearing reainer removed...
so turns out after all that, i do need to remove retainer and bearing to then fit bracket on again first....
am i missing something?????

Re: disc brake conv question

Posted: Tue Jan 25, 2011 6:12 pm
by suzolla
Would not have thought you need to remove the bearing as the bracket should be C shaped so that it will fit over the axle and then bolt on.
See the SNR MR2 ones in the link http://www.snr4x4.co.nz/brakes-c-23_13.html?osCsid=62cdde36b9a36c487ba6cd5b4e62df5e

Cheers
Tim

Re: disc brake conv question

Posted: Tue Jan 25, 2011 6:28 pm
by J_Dub
suzolla wrote:Would not have thought you need to remove the bearing as the bracket should be C shaped so that it will fit over the axle and then bolt on.
See the SNR MR2 ones in the link http://www.snr4x4.co.nz/brakes-c-23_13.html?osCsid=62cdde36b9a36c487ba6cd5b4e62df5e

Cheers
Tim


thats what i assumed, that cause they are 'C' shaped they will slip over and bolt up, but they dont, the 'C' is to small... :?

Re: disc brake conv question

Posted: Tue Jan 25, 2011 6:39 pm
by suzolla
Perhaps they fit on the inside of the axle flange, hence the requirement for the spacers for the calipers.
Cheers
Tim

Re: disc brake conv question

Posted: Tue Jan 25, 2011 7:00 pm
by J_Dub
they dont fit over anywhere, not the axle housing side or over the retainer side between the hub..
seems odd that you gota strip everything just to fit a bracket to hold the caliper.. i guess if thats the case then thats the case

Re: disc brake conv question

Posted: Tue Jan 25, 2011 9:59 pm
by Smurf
chuck up some pics?

Re: disc brake conv question

Posted: Wed Jan 26, 2011 5:32 am
by J_Dub
i will tonight. but its as simple as that the "C" is too small to fit over anything... why have it notched out to fit over something when it doesnt :roll:

Ive found out these were designed for the 130, so im guessing no ones fitted them to a pre 130 and assumed it will work without stipping axles :roll:

Re: disc brake conv question

Posted: Wed Jan 26, 2011 5:34 am
by J_Dub
whats peoples opinions if i was to remove a section of the bracket (1 hole) which ment there was only 3 mount points???

Re: disc brake conv question

Posted: Wed Jan 26, 2011 6:36 am
by nstacey
J_Dub wrote:i will tonight. but its as simple as that the "C" is too small to fit over anything... why have it notched out to fit over something when it doesnt :roll:

Ive found out these were designed for the 130, so im guessing no ones fitted them to a pre 130 and assumed it will work without stipping axles :roll:


Could see if you can check out some 106 series rear axles.maybe they have the same size hub as a 130?? From what I understand the 130 has a wider rear end so a 130 axle wouldn't suit.

Re: disc brake conv question

Posted: Wed Jan 26, 2011 7:18 am
by Smurf
J_Dub wrote:whats peoples opinions if i was to remove a section of the bracket (1 hole) which ment there was only 3 mount points???



my rear disc bracket only has three mounting holes,

Re: disc brake conv question

Posted: Thu Jan 27, 2011 7:35 pm
by J_Dub
well fcuk now it seems the calipers wont work.
to have them mounted up top they hit the leaf springs.. :? :evil:
I just cant see how these calipers work with a leaf sprung lux, way to wide in the body......

Re: disc brake conv question

Posted: Sat Jan 29, 2011 12:03 pm
by J_Dub
right either the rotors are wrong or the calipers are, the calipers seem the same as all the others have used and look the same as the pics ive seen on here. The rotors the calipers came off of the mr2 were 15mm and the rotors i got are 18mm, these rotors wont fit these calipers, do i get the rotors turned down or are the rotors the wrong model??

Re: disc brake conv question

Posted: Sat Jan 29, 2011 4:43 pm
by nstacey
Hey, don't know if this helps you any, but these are the calipers I got at pick a part off a 91 or so MR2,

Image

Re: disc brake conv question

Posted: Sat Jan 29, 2011 4:51 pm
by J_Dub
yep there the same

Re: disc brake conv question

Posted: Sat Jan 29, 2011 5:09 pm
by Sadam_Husain
Shit your having dramas with these brakes and usually the hard bit is setting up the handbrake cables that you arent going to have to do?

would thinner front solid rotors instead of vented rotors fit the 15mm gap in the callipers?

Re: disc brake conv question

Posted: Sat Jan 29, 2011 5:14 pm
by J_Dub
yea, figured I had it right as theres apparantly only 1 size rotor on the LJ78 prados... so cant go wrong there and ive got the non turbo sw20 callipers..
1 of them must be wrong so i will wait and see..

Re: disc brake conv question

Posted: Sat Jan 29, 2011 6:09 pm
by J_Dub
eerrr, Ive sorted it, ive got it to work.
maybe having a break and taking the dog for a run was a good thing :oops:
1 side all bolted up and ill leave as that for now, just so the truck is mobile and i can get on with the rest.
Promise ill do the wide axle swap before its maiden voyage though to get them calipers up high :D
pic to come

Re: disc brake conv question

Posted: Tue Apr 26, 2011 5:43 pm
by Big
I've got some mr2 calipers on the way and am trying to srot out the lj78 rotors..? did you have a aprt number and or price from where you got them..?

Re: disc brake conv question

Posted: Tue Apr 26, 2011 6:01 pm
by J_Dub
$140 if i remember rightly from bnt
theres only 1 rotor listed for the lj78 i think was the case

Re: disc brake conv question

Posted: Tue Apr 26, 2011 6:09 pm
by Big
each or a pair..?