Rear hubs for disc conversion - L series

YouTube · Post by **El_Freddo** » Fri May 11, 2007 2:24 pm

Hello hello.

I would ultimatly like to do a rear disc conversion but cannot find a 4wd rear hub to fit the disc to my 4wd L wagon. I have access to Front wheel drive rear disc calipers but not the hub to mount them to my car...

Does anyone know if the rear 4wd disc hub is the same as the front hub? Meaning that i could take a front hub a slot it on the rear with the rear disc size bolted on. It would be very convienient if this was the case, 99% of the time things are not convienent hence the questions.

The other question is do i have to add a restrictor to the rear line or change the brake master cylinder? And if i need a restrictor, where on the car is it located? And i realise i'll have to bleed the lines before i take the car out again...

All input welcome.

Cheers

stamp_licker · Post by **stamp_licker** » Fri May 11, 2007 7:16 pm

front hub won't fit its got different splines.

dfoyl · Post by **dfoyl** » Fri May 11, 2007 7:24 pm

No, you don't need to change anything in the lines. It's just a straight swap. I know of 1/2 a dozen US guys on USMB who have sets available for about $100 US / $120 AUS - and as of the 14th of May USPS will be charging by volume and not weight for airmail so you can get the discs a heck of a lot cheaper if they pack them really tight.

Also, try to get the pads from the US - the only equivalent I know of here are the Vortex pads and they're not cheap / common. You can get pads for under $25 US / $30 AUS out of the states.

Dean.

Fang · Post by **Fang** » Fri May 11, 2007 7:45 pm

dfoyl wrote:I know of 1/2 a dozen US guys on USMB who have sets available for about $100 US / $120 AUS - and as of the 14th of May USPS will be charging by volume and not weight for airmail so you can get the discs a heck of a lot cheaper if they pack them really tight.

Have to agree with this - I got mine from a fellow in New Mexico - after freight and the cost of the brakes themselves it was was still lower than the domestic asking price. And that was when USPS charged via weight.

YouTube · Post by **El_Freddo** » Mon May 14, 2007 1:20 pm

So the way to get a set of rear discs is to buy them in the US and post them to austraila using the United States Postal Service yeah?

Would getting them from NZ be an option (maybe slip in an AWD L gearbox to, i think they have them over there don't they?)

Bugger that the front hubs don't fit the rear, wonder if the outter shaft cup can be changed with a front one... I'm thinking the axle thickness would be the problem here with the front outter cup spline diametre being greater than the rear - and longer maybe...

Cheers

Fang · Post by **Fang** » Mon May 14, 2007 3:31 pm

Ye olde PM sent, Bennie!

discopotato03 · Post by **discopotato03** » Mon May 14, 2007 8:05 pm

One wonders if its possible to grab a 4WD rear drum and machine the drum off leaving a hub/drive flange complete with studs or holes anyway . Adapt a disk and make up a caliper mounting plate to suit say a Nissan MR30 rear caliper which is very similar to the RX-T rear caliper except its got cable hand brake link arms . All sorts of options once you beat the "where the hell do I get a suitable splined hub from" issue . Every brake drum IS one .

Cheers A .

90brumby · Post by **90brumby** » Mon May 14, 2007 8:36 pm

you could do that i wonder how the cops would like this tho

YouTube · Post by **El_Freddo** » Tue May 15, 2007 3:04 pm

90brumby wrote:you could do that i wonder how the cops would like this tho

I agree with 90brumby here... I do want these parts and my car to be a little different BUT i want to do it so that i don't get taken off the road for anything that i've made up for these bits to fit...

So factory parts that are "bolt on" replacements are the way for me...

All of this said, if you get it engineered, your clear... but i don't have that sort of money.

Cheers

discopotato03 · Post by **discopotato03** » Tue May 15, 2007 3:12 pm

Most cops here don't look twice at an old world Subaru let alone whats inside std wheels . Whats to see ? A disk over the "hub" like just about every other car has nowdays and a non handbraked disc caliper . MR30 calipers like Aus spec 200SX S14/15 use the same sized piston - in fact the floating section of the caliper is virtually identical down to the pads except for the mechanical park brake actuation system . When you think about it the drum with integral splined hub takes no less load in drum form than disc form so no issue except maybe widening the track by double the thickness of the disc hat section where it goes over the hub . I reckon you could correct this by taking a similer amount off the inner end of the hub and using a neatly fitting spacer at the outer end if the nut was likely to run out of thread on the CV/stub axle .

The only potential danger is not making the caliper mounting plate strong enough . People who do fabrication work for Rally cars make these sorts of bits all the time you just have to find a good operator . If he's on the ball he'll make it so some common/cheap splash/stone gard fits so no ones going to see anything they wouldn't expect to anyhow .

Quite frankly I think the rear disc brakes on RX-T's are woefully small and I seriously doubt they work any better than the std drums do , in fact unless you take your car swiming often where drum brakes take longer to dry out and work properly the difference will be zip . If your car was a serious rally effort it won't be wearing its std brakes unless class regs force you . They normally have the same sized brakes (discs) all round and adjustable bias valves and hydraulic hand brakes etc .

If you really want to be ADR compliant then you must use the factory parts or develop alternatives and get an engineers certification .

Your call .

stamp_licker · Post by **stamp_licker** » Tue May 15, 2007 7:50 pm

discopotato03 wrote:One wonders if its possible to grab a 4WD rear drum and machine the drum off leaving a hub/drive flange complete with studs or holes anyway . Adapt a disk and make up a caliper mounting plate to suit say a Nissan MR30 rear caliper which is very similar to the RX-T rear caliper except its got cable hand brake link arms . All sorts of options once you beat the "where the hell do I get a suitable splined hub from" issue . Every brake drum IS one .

Cheers A .

A few cars have been converted to 5 stud this way.

90brumby · Post by **90brumby** » Wed May 16, 2007 12:22 am

i might have to have more of a look into this if it is gonna wrk it will save a fair bit of dosh

YouTube · Post by **El_Freddo** » Wed May 16, 2007 2:20 pm

discopotato03 wrote:Most cops here don't look twice at an old world Subaru let alone whats inside std wheels .

In benders it seems a passion of hate for the local boys (cars). There was recently a road-worthy check station on one of the main roads, if they couldn't find something they looked harder/further into the car's mechanicals. I think they didn't like my 3 spotties across the front but all of them looked and left it to the next officer (my opinion anyway).

discopotato03 wrote:Quite frankly I think the rear disc brakes on RX-T's are woefully small and I seriously doubt they work any better than the std drums do. If your car was a serious rally effort it won't be wearing its std brakes unless class regs force you . They normally have the same sized brakes (discs) all round and adjustable bias valves and hydraulic hand brakes etc .

The reason i want the standard disc brakes is that they are easier to check and work on than that of the drums, i'm not in it for the performance side of things, my car is not a rally car and if it is ever treated as one its in the paddock doing circle work in the mud

discopotato03 wrote:If you really want to be ADR compliant then you must use the factory parts or develop alternatives and get an engineers certification .

Yep, pretty much what i've thought.

What i wrote before your reply was in no way intended to have a stab at you, its just about what i'm trying to achieve in a standard/cheapest way that will satisfy any authority that may question my car.

I realise that your doing up your RX and your opinions seem very well suited to your application. If you'd like to talk about your brake options for that i would gladly read on but I will probabily be of no use (all i know is the bratgeebah's brake upgrade kit would be it...)...

Cheers

discopotato03 · Post by **discopotato03** » Wed May 16, 2007 7:41 pm

No worries , I guess you'll have to hold out for a std set or import some from the US . If you had time and a variety of wreckers you may stumble across something similar but its that stud pattern thats difficult to match .

Cheers A .

Ben · Post by **Ben** » Wed May 30, 2007 12:42 pm

discopotato03 wrote:One wonders if its possible to grab a 4WD rear drum and machine the drum off leaving a hub/drive flange complete with studs or holes anyway .

Do this if you want to die!

I looked into this a couple of years ago and went so far as to make some up from some drums I had. The amount of metal on the outside of the stud holes is insufficient for the loads of the vehicle.

The only cost effective option in Australia for better than L series brakes is Bratgeebah's kit.