89 Brumby Brake Improvments

AUSubaru Technical Manual. Collaborative Tech Manual for ALL Subarus.
User avatar
steptoe
Master Member
Posts: 11582
Joined: Thu Oct 06, 2005 10:00 am
Location: 14 miles outside Gotham City

Post by steptoe » Tue Nov 26, 2013 6:27 pm

O..K.... >>> ??? I coulda swore the ears with holes that the calipers bolt to was integrally cast on L's and MY with the front wheel bearing hub.

One thing I am sure we will both agree on is the bolt pattern (centre to centre) of the MY front brake caliper is less than that of the L

...this a WA joke on the east coast ?? :(

this is starting to make me think of the cartoon of a blind bloke in bed with a sighted woman, with his assistance pooch helping with cough, directions .....

going back to read Pauls instructions..

Gees, Paul, care to do a step by step write up ? Pics, a lot of pics !!

User avatar
steptoe
Master Member
Posts: 11582
Joined: Thu Oct 06, 2005 10:00 am
Location: 14 miles outside Gotham City

Post by steptoe » Tue Nov 26, 2013 6:34 pm

Dawning on me now, and thinking the calipers I have pulled off are always dirty and are at the two 17mm head bolts ...maybe the caliper breaks down a bit further under the crud and use an MY caliper mounting bracket I never knew existed.


Think I am going out to shed to get hands dirty .....

EDIT : Where did I get the idea of swapping calipers onto existing MY anchor brackets?. Paul no said that, he said complete front calipers and their anchor brackets.

L Series front calipers are a beefed up version when it comes to the bolt up sizes. Stuff still ain't interchangeable :(

This is exactly what I have tried to do with non L Series RX calipers with anchor brackets!

The anchor bracket to hub assembly bolts on MY are ~102mm from centre to centre.

All the L Series stuff - exhibit A is 10/85 GLTA , exhibit B is 11/86 Touring Wagon, exhibit C 3/87 turbo Vortex FWD

the anchor bracket bolts are ~123mm centre to centre.

What we need now is an L RX owner to get under and measure !!

both MY and L series front caliper pistons measure ~53.85mm

User avatar
TOONGA
Elder Member
Posts: 5335
Joined: Sat May 30, 2009 10:15 am
Location: Australind closer to where they divided by zero
Contact:

Post by TOONGA » Tue Nov 26, 2013 6:44 pm

steptoe wrote: care to do a step by step write up ? Pics, a lot of pics !!
If some one cares to donate a working set of "L" front parts (rear is done already)I will do the picture walkthorugh with my brumby being the recipient :)

And no Im not taking the front brakes off my vortex to do it.

TOONGA
Image
PJ Gone but not forgotten
JETCAR AKA the sandwedge Rusted in pieces

User avatar
steptoe
Master Member
Posts: 11582
Joined: Thu Oct 06, 2005 10:00 am
Location: 14 miles outside Gotham City

Post by steptoe » Wed Nov 27, 2013 7:44 am

Just thinking... I once wanted L front brakes in order to satisfy conversion of EA81 to EA82T imagined requiremnts, would also be good brag stuff for a signature line, bigger pads makes sense, but having tried my current MY front and L rear disc - couldn't ask for better ! Besides, i still have new front discs and pads to use up somewhere :) Bought on impulse :)

If all the above turns out I have not looked hard enough, Phiz and Trev gonna be a little miffed too !

User avatar
Silverbullet
Senior Member
Posts: 2858
Joined: Mon Aug 23, 2010 6:20 pm
Location: Adelaide

Post by Silverbullet » Wed Nov 27, 2013 6:32 pm

Excuse my ignorance but what's better about the L series front disc conversion? Bigger discs? I only have MY parts lying around so I can't compare :rolleyes: And Paul keeps mentioning L series RX turbo onto MY, are the RX turbo front discs different again to normal L series fronts?

Looks like I'll have to go further into this conversion since I'm planning on L series self adjuster rear drums on my wagon, but someone please tell me the MY and L series use the same banjo bolts for the brake lines :rolleyes:
Will it ever end!?
-EA81 TWIN CARB!!!!
-L series 5 speed
-Custom paint job
-2" lift
-Full custom re-wire
-L series front end
Image

User avatar
steptoe
Master Member
Posts: 11582
Joined: Thu Oct 06, 2005 10:00 am
Location: 14 miles outside Gotham City

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 !!

User avatar
Silverbullet
Senior Member
Posts: 2858
Joined: Mon Aug 23, 2010 6:20 pm
Location: Adelaide

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
Will it ever end!?
-EA81 TWIN CARB!!!!
-L series 5 speed
-Custom paint job
-2" lift
-Full custom re-wire
-L series front end
Image

User avatar
steptoe
Master Member
Posts: 11582
Joined: Thu Oct 06, 2005 10:00 am
Location: 14 miles outside Gotham City

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 :(

User avatar
RSR 555
Elder Member
Posts: 6951
Joined: Sat Nov 10, 2007 10:42 am
Location: ATM... stuck in Rockingham

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.
You know you are getting old when the candles on your birthday cake start to cost more than the cake itself.

RSR Performance
Home of the 'MURTAYA' in Oz
Subaru Impreza WRX based Sportscar
[SIGPIC][/SIGPIC]

Disclaimer: Not my website but hyperlink here to Subaru workshop manuals

User avatar
steptoe
Master Member
Posts: 11582
Joined: Thu Oct 06, 2005 10:00 am
Location: 14 miles outside Gotham City

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 !

User avatar
steptoe
Master Member
Posts: 11582
Joined: Thu Oct 06, 2005 10:00 am
Location: 14 miles outside Gotham City

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

User avatar
Silverbullet
Senior Member
Posts: 2858
Joined: Mon Aug 23, 2010 6:20 pm
Location: Adelaide

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.
Will it ever end!?
-EA81 TWIN CARB!!!!
-L series 5 speed
-Custom paint job
-2" lift
-Full custom re-wire
-L series front end
Image

User avatar
steptoe
Master Member
Posts: 11582
Joined: Thu Oct 06, 2005 10:00 am
Location: 14 miles outside Gotham City

Post by steptoe » Fri Nov 29, 2013 5:18 pm

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

User avatar
steptoe
Master Member
Posts: 11582
Joined: Thu Oct 06, 2005 10:00 am
Location: 14 miles outside Gotham City

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 !

User avatar
steptoe
Master Member
Posts: 11582
Joined: Thu Oct 06, 2005 10:00 am
Location: 14 miles outside Gotham City

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 :(

User avatar
Subydoug
Junior Member
Posts: 988
Joined: Wed Feb 08, 2012 10:19 pm
Location: Carlisle WA

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.

Regards

Doug

User avatar
steptoe
Master Member
Posts: 11582
Joined: Thu Oct 06, 2005 10:00 am
Location: 14 miles outside Gotham City

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

User avatar
Gannon
Senior Member
Posts: 4580
Joined: Sat Nov 05, 2005 10:00 am
Location: Bowraville, Mid Nth Coast, NSW

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"
Current rides: 2016 Mitsubishi Triton GLS & 2004 Forester X
Ongoing Project/Toy: 1987 RX Turbo EA82T, Speeduino ECU, Coil-pack ignition, 440cc Injectors, KONI adjustale front struts, Hybrid L Series/ Liberty AWD 5sp
Past rides: 92 L series turbo converted wagon, 83 Leone GL Sedan, 2004 Liberty GT Sedan & 2001 Outback
------------------------------------------

User avatar
RSR 555
Elder Member
Posts: 6951
Joined: Sat Nov 10, 2007 10:42 am
Location: ATM... stuck in Rockingham

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
You know you are getting old when the candles on your birthday cake start to cost more than the cake itself.

RSR Performance
Home of the 'MURTAYA' in Oz
Subaru Impreza WRX based Sportscar
[SIGPIC][/SIGPIC]

Disclaimer: Not my website but hyperlink here to Subaru workshop manuals

User avatar
RSR 555
Elder Member
Posts: 6951
Joined: Sat Nov 10, 2007 10:42 am
Location: ATM... stuck in Rockingham

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.
You know you are getting old when the candles on your birthday cake start to cost more than the cake itself.

RSR Performance
Home of the 'MURTAYA' in Oz
Subaru Impreza WRX based Sportscar
[SIGPIC][/SIGPIC]

Disclaimer: Not my website but hyperlink here to Subaru workshop manuals

Post Reply

Return to “Tech Manual”