89 Brumby Brake Improvments

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steptoe
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Post by steptoe » Wed Nov 27, 2013 6:35 pm

bigger !

bigger diameter, more pad surface area. More plentiful than MY. The last set of pads I fitted, cheap arse no name I can recall, made a jarring noise on a particular turn, just in front of mates workshop :( , for which I copped crap for. Priced a rebuild of caliper - then , about three years ago, maybe four - $150 each. So to pick up some more common L calipers and do this .....

I kept the front brakes off my impressive braked L Touring Wagon just for this ! Got pads, rotors and hopes the splined hubs too - making room for more junk or Jonno in the parts shed !! Current pads are at the end of their service life. Nice timing ...better get it done and sorted before Xmas break !!

I might be the pic supplier ! Well, no, I won't be, just yet

Just been looking at a pair of L calipers. The calipers are cast and they bolt to a bent pressed metal gold zinc plated bracket via one bolt with 12mm head - the bolt undone to replace brake pads. The other point of contact is the other greased slider ! So, must be the sliders that have a common centre to centre measure and the L caliper slides on to the MY caliper brackets slider pin. Guessing L pads are still used and fit between the gold zinc plated bracket ?

Now, the technical engineer comes out to measure the sum of the fluid in all lines and calipers at maximum pad wear to determine if a larger capacity brake fluid reservoir is required - totally not taking into account the level should be topped up as it drops below max fill line.
Paul states this is with L Series RX front disc rotors, splined hubs and calipers and knows not if plain old L Series stuff works - think it is no different. RX masters were different and interchangeable at same time. Running a normal one in my GLTA

Where was Paul when this big debate was on ???

Sam...you had an L for parts ...sounds like you chucked all the good bits !!

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Post by Silverbullet » Wed Nov 27, 2013 8:34 pm

steptoe wrote: Sam...you had an L for parts ...sounds like you chucked all the good bits !!
Meh, I didn't think of it at the time and if I'd stripped it down any further they wouldn't have taken it away for free :p
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Post by steptoe » Wed Nov 27, 2013 9:53 pm

Starting to think (ouch) , Sam, always another L waiting out there with your name on it :) ,

QUESTION for Paul >>brake pads used ? thinking the anchor bracket is MY, remains MY, isn't it this that dictates the pads ? If MY DB426 are used, no greater pad contact.

EDIT :wish Paul stopped me from going off on this tangent ^^^ - thought it was the answer, but it ain't. Misread his clear instructions :(

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Post by RSR 555 » Wed Nov 27, 2013 11:55 pm

Ok.. I'm not sure about the later model (series 2) L.Series brakes if these are different but I've only used the 85/86 model (series 1) L.Series brakes from the Aussie RX Turbo sedans. These are about 10mm overall larger in disc diameter on the front and the only pads I use are Bendix 4WD ones and if the customer wants more stopping, then I go with slotted discs up front. I don't believe there is any different in the front piston diameter, as I use the same tool to twist the piston back on both the MY and L.Series models. Most of the time, the extra stopping power of the rear discs really is enough.
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Post by steptoe » Fri Nov 29, 2013 6:43 am

And, something else that comes to mind - reports of some MY rims not fit L series due to bigger front brakes. This might mean that anyone adding L fronts may not be able to fit their rims back on !

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Post by steptoe » Fri Nov 29, 2013 3:56 pm

OK, amidst the hooha of havin' L Series front discs, I've had a look at a few things. My 10/84 complianced Brumby has the brakes all brake books list for mar 85 onwards models they take DB426 pads, not the DB326 or DB396. The discs are ~ 230mm max diameter and ~ 18mm thickness new.

Mar '85 is also when my Bendix book starts off with L Series, so maybe they upgraded the Brumby brakes to same disc thickness same time.

Gregories note minimum pad thickness is 7.5mm (not the meta-to- metal some peole think ! ) ! About half what they start out as !!

For comparison - the factory specs of an L front disc is 18mm x 242mm.

The advantage for MY owners could be for those with the earlier 12mm max thick solids listed in my Gregories manual . ? think it even says they are vented ?

The factory manual calls the bracket a bracket, Gregories call it an anchor. This is the bit that confused me - obviously - it aint used in the transplant. So, retaining the MY anchor bracket , pretty sure this dictates the pads used, so looks like the L Series pads with an extra 20mm length aren't used in the transplant either.

So, the gain can be bugger all if you have the fatter vented discs on later model MY's - unless it was to satisfy an engineer requiring the brakes from the engine donor vehicle if upgraded to EA82T or sumptin' !?

Your current disc thickness could be an issue to consider, and if you got the bits and just wanna say ya done it :) Or the binding caliper noise in mine that comes and goes ( I still blame the tight arse pads)

Oh, yeah, factory manual for the S1 Paul mentions - same disc all models L's RX and Vorts

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Post by Silverbullet » Fri Nov 29, 2013 4:51 pm

Well when I was still driving my wagon it had factory standard solid front discs, so even MY vented discs would be an improvement. Oh and as for MY wheels on an L yes it cam be done; the wheels you see below in my sig pic are currently on dads L series, albeit alot dirtier now. And it's barely noticeable but the tyres stick out from the guards, probably less than 5mm. Currently I also have wheels I pulled off that scrap L series on my Brumby, so completely interchangeable it seems.
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Post by steptoe » Fri Nov 29, 2013 5:18 pm

think it is the MY sportswagon rims that won't go an L Series ......

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Post by steptoe » Fri Nov 29, 2013 5:30 pm

RSR 555 wrote: Parts required are...

Front end:
2x Front brake rotors (complete with drive hubs) and LH & RH Front brake calipers (complete with mounting brackets).

The fronts are a straight swap, just a case of removing the complete brake caliper (which includes the caliper mounting bracket) and remove the rotor, then fit the RX Turbo rotor and fit the RX Turbo caliper.
I am reading this again and says complete with mounting brackets that is, bolt the S1 calipers and anchor bracket to MY front hub assy...this is where I came unstuck before - trying to bolt a complete caliper and anchor bracket (aka mounting bracket) to an MY hub.

Thought I read before not to use the anchor bracket - chasing arse whichever way ! Gees, if I could pull this off I have a lifetime of used front pads to use up ! and about 40 mm square extra brake pad !

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Post by steptoe » Fri Nov 29, 2013 6:00 pm

Jeepers, just wondering, I have been checking out a front caliper of an 84 MY FWD not a 4WD ! Surely , no different ?? MY FWD caliper anchor bracket to hub assembly bolt spacing is ~102mm. The L Series stuff, FWD, 4WD, 4WD turbo (just not S1 RX :( are all 123mm centre to centre !

Sending self on a wild goose chase so far :(

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Post by Subydoug » Fri Nov 29, 2013 8:33 pm

Had a look for you'll. My wagon is dated 11/82. Disks on the front are solid, not vented. Diameter would be close to 220 or 230mm, couldnt measure it that well. Looks like the whole knuckle with caliper bracket is one piece like jonno said earlier though it was pretty filthy in there and I wasnt too keen to dig in. Also found out the annoying noise Ive been hearing lately. Talk about a flogged out ball joint :D.

Im pretty sure the disks on my FWD vortex are vented. Not sure on sizes and pads or anything else. I stops orders of magnitude better then the wagon. Donno weather its because of disk rear, different vac assist, master cylinder...who knows but I do feel its more to do with just the rear disks.

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Post by steptoe » Sat Nov 30, 2013 6:46 am

..... the 86 - 92 parts catalogue lists all front L Series and Vortex varieties as having same front caliper components right through the years range with the exception of brake pads changing for asbestos and the europe market ? Only other change was the bolt that hold the handbrake cable bracket.

The component the workshop manual calls an anchor, Gregories - a bracket, the parts diagram calls it a support!

An earlier post I deleted was thinking out too loud, thinking if the anchor support bracket remained with the carit would limit the pads to the original smaller pads.

The gain would be as Paul suggests, being able to use the L pad which is about 40mm 2 larger area.


What is it Gannon says ?? "Photos or it never happened "

scratching head .....

think Gregories states 13/16" or metric equivalent for both MY and L master cyl bores

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Post by Gannon » Sat Nov 30, 2013 8:29 am

steptoe wrote:.....
What is it Gannon says ?? "Photos or it never happened "
My usual response if somebody says to me "I banged the hottest sheila last night"
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Post by RSR 555 » Tue Dec 03, 2013 12:45 pm

Ok.. so you had enough yet?

The L.Series fronts will not fit the MY Series. Only the rears will swap over, so I highly recommend you use the RX Turbo disc setup but they are getting harder to find.

Jonno and Ray, if you want better front brakes then just go with the post-1983 Leone vented and slotted discs with a set of high quality brake pads
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Post by RSR 555 » Tue Dec 03, 2013 2:00 pm

Just been speaking to my brake man and he said there is 2 sizes of disc rotors for the Brumby. 230mm and 242mm both rotors use the same caliper and pads. For upgrades he recommends you use the 242mm rotor that has slotted and dimples on them, couple this with a set of EBC Ultimax2 pads and you'll be very impressed.
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Post by steptoe » Thu Dec 05, 2013 5:08 pm

RSR 555 wrote:Ok.. so you had enough yet?

The L.Series fronts will not fit the MY Series.
I'm still trying to digest this bit after posts from reliable sources said they did !
I got some calipers heading for the bin after salvaging the pistons for a budding hoarder :p

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Post by Silverbullet » Sat Sep 13, 2014 5:06 pm

Didn't want to put this in the "what did you do to improve your subie" thread so, digging up an old thread after the info in it has let me down! Paul! :p Well to be fair towards the end he has said they won't bolt up.

After so many posts saying the L series front calliper and mounting bracket will bolt up to the MY steering knuckle/bearing housing, when I just tried it with my new 87' turbo Vortex bits there is no way they will bolt up. Jonno had it right earlier, the bolt center distance for the 2 x 17mm calliper bolts is different. With the MY being closer together. Also thought about using the MY anchor bracket with L series calliper but that is impossible, design is too different.

Only way I can see to get these Vortex discs and callipers on my wagon is to use the Vortex bearing housing with L series control arms. Which I don't know if I can be bothered doing since I've already got new bearings and bushes installed in the MY housings. Plus it will make the front wheel track wider than the rear, not sure if this is a good idea or a good look. Because I needed to put these Vortex hubs on (to suit the disc rear, hubs have been changed to 4x114.3) I have bolted the Vortex front hub to the MY disc, that works nicely. Looks like my only option for a MY front brake upgrade is to use the biggest vented discs that were an option for later models.

Backing plates, the 2 bolt spacing is different, won't bolt up to MY wheel bearing housing
Image
Calliper anchor bracket(?) MY in foreground, Vortex behind. Too different to be interchanged
Image
Vortex front hub bolted to crusty old MY solid front disc...it works and the wheels go on now but I plan on using vented discs later
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steptoe
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Post by steptoe » Sat Sep 13, 2014 6:36 pm

Vented discs use a different pad, maybe different caliper too. Think TOONGA started this L stuff fits ....

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better get Paul to delete this text of his then!

Post by steptoe » Sat Sep 13, 2014 6:46 pm

at least one charater added ..
RSR 555 wrote:I can confirm that I have made the L.Series RX Turbo brake upgrade to many MY Series model cars over the years. The most recent one completed is Maple the beige coloured Brumby that was owned by Jay Jay. I shall refer this post to Maple as she had the complete RX Turbo conversion. There is no modification to any of the parts and there is no change to the alignment of the wheels as we are not touching the steering, nor the bearing hubs.

Parts required are...

Front end:
2x Front brake rotors (complete with drive hubs) and LH & RH Front brake calipers (complete with mounting brackets).

Rear end:
2x Rear brake rotors (complete with drive hubs), LH & RH Rear brake calipers (complete with mounting brackets), LH & RH Backing plates (including bolts & nuts) and LH & RH Brake flexible brake lines.


The fronts are a straight swap, just a case of removing the complete brake caliper (which includes the caliper mounting bracket) and remove the rotor, then fit the RX Turbo rotor and fit the RX Turbo caliper. The rears are little more interesting. You need to remove the drum and all the brake shoes, then remove the backing plate (at this point you can throw all these MY parts in the bin), then you'll need to fit the RX Turbo rear backing plates, then the rotors and calipers, then change out the brake lines and once all fitted up, you'll need to give the system a good bleed. I find a good time to replace your fluid.

I could go in to a lot more details/procedure about the swap but it's really a straight forward swap that you'll be able to work it out just by looking at the parts.

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Post by Wooster » Tue Oct 28, 2014 11:17 am

And as you guru's said, the change over to rear disc brakes on the brumby is a major improvment . Agreed 100 & 11 percent

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