Hi All,
I've compiled this and thought you might find it helpful, let me know if you need more info or more pics (struts look good now the’re painted).
Cheap brake upgrade for RWD Corollas (AE71 or similar).
After looking through endless web pages for information on a cheap brake upgrade, and not finding anything useful (some people have a different view on what is cheap my definition is as cheap as possible) I've decided to throw this article together.
My set up (not yet cleaned and painted)
Close up:
I've used T18 struts as the basis of my upgrade as they are fairly easy to find (compared to AE86 struts) and they're 51mm in diameter and this means strut inserts that fit AE86, Celicas, Coronas etc will fit these.
Parts needed:
Suitable front struts, in my case from a T18, but you can use the existing struts.
VB to VK Commodore Girlock brake callipers are cheap and easy to find, rebuild kits are dirt-cheap and you can take your pick of brake pads (from cheap and nasty to race spec pads).
New or good used brake discs from a Mitsubishi Magna TN, TM or TP the early model before the V6 Magnas came out and 24mm Thick!! + they look big and meet on the work bench!
Depending on the type of calliper on your standard struts, you may have to make or get made up an adaptor to bolt up the Commodore callipers.
If you're lucky, your standard brake callipers will be Girlock with a 75mm mounting distance between bolt centres. If this is the case you probably wont need the adaptor as the Commodore calliper also use the same bolt spacing and already have a bigger offset built in to cater for the original Commodore (disc) set up.
You need to slightly mod the calliper slider (the part that bolts to the mounting bracket) as it catches on the edge of the strut when you try to bolt it up, youll see what I mean when you try it on the strut for the first time (look at the photo to see how I fixed mine) I ground off a little metal with a bench grinder, taking a little off at a time so I didn’t remove any more metal than I had too.
The slider is very solid and the small amount of metal I removed won’t affect its strength (but check with your local transport organization if youre concerned).
Calliper mod:
One last thing you will need is 4 x 4mm wide spacers to suit 12mm bolts. I got some made up out of alloy but you may be lucky and find a suitable washer off the shelf some were. Just remember if you use second hand discs you can get away with thinner washers (just) but if you upgrade to new discs latter on youll find your calliper mounting brackets rub on the outside of the disc (trust me I used old discs to set up my brakes to start with and found this out once I installed my new discs).
Calliper slider, adaptor bracket and 4mm spacers assembled:
Brake building 101:
If you have one, mount your strut on a bench in a strong vice and unbolt the original brakes and hub assembly. Once the hub is off the strut you need to unbolt the disc from the hub only 4 bolts and a gentle tap with a hammer to slip them off if you cant get them off with a gentle tap you havent undone all 4 bolts so check again.
Now degrease your hubs, if you intend on using longer wheel studs nows the time to remove the old ones. early model Hilux 4wd and drum brake Land Cruiser studs are about 8mm longer and fit with a small adjustment (plus there cheap mine cost $4 each for new studs from a 4wd shop, they do need about 3mm of the spline ground down so the studs will fit in to the hubs)
Now you need to get your hubs turned down to 142mm outside diameter so the new discs can slip over the top of them. Dont worry about the centre hole being too big, the studs and the slip fit over the hub will keep the disc in place once the wheel and wheel nuts are fitted.
Mounting brackets.
I made my bracket from a length of steel bar: 10mm (thick) X 40mm (wide) X 150mm (long) ($6 from Sims Metal for a 1 mtr) with 4x12.5mm (or in old measurements) holes centred on the bracket to give the correct mounting points (look at the pic of the bracket for a better idea). As there is a slight difference in mounting offset with the new calliper, you need 2 x 4mm wide spacers (per calliper). The ones I have are made from Alloy but steel will do just fine, the only critical dimension to note is that they must be 4mm wide. Any less any you run the chance of new disc rotors rubbing on the inside edge of the mounting bracket (new discs are 24mm thick!!).
Calliper hose:
If youre car has Girlock brakes already you can run the same hoses on the new brake set up (threads should be the same & the calliper to hose mount should be fine as well).
Master cylinder upgrades:
I havent looked in to this yet but the ex-Commodore callipers should be a similar bore size to the old Corolla ones meaning the brake pedal feel and travel will be the same as before (except the car will pull up significantly better with no fade).
Other things to think about:
If youve gone this far why not spend a bit more and replace the wheel bearings, ball joints and bushes? All up these parts wont cost that much but worn parts will effect the ride and handling significantly and any wear problems you had before will be increased once you bolt up the bigger and better brakes.
Cheers
Chris
Awesome post Chris...excellent cheap upgrade.
If using 86 struts are there any changes to be made. ie are they pretty much the same as the T-18 ones?
Will be really interesting to see how improved the car is under braking now. Are you far off completing your setup?
Also what are your thoughts on brake bias. Are you going to install a controller?
R
ArJay
I don't have an AE85/86 strut so I don't know. I can measure my T18 struts and post the results, as long as the caliper mounting bracket has the same off set and the front face of the hub is the same it should all fit fine.
chris
very good brakes for the money
all the rally guys use these
Yeah, I'm loving the Commodore calipers and the Magna disks. Like you said Chris, cheap as to rebuild and replace...awesome!
So the disks are a direct bolt up to the T-18 stud pattern/PCD?
What are you doing about your rears Chris? You running drums still?
Commodore caliper rebuild kit direct from the Holden dealer cost $12 odd each plus brand new pistons cost $20 each!!! I love it!!.
Haven't worked out rear brakes yet, but I'll be looking very closely at Pintara/Skyline (R31) rear discs as they run a Borgwarner diff (same as my wagon) so should have a good chance of bolting on straight up.
I'll keep you posted.
Chris
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