Hilux - BA Rotors - Nissan GT Calipers

[infotechplus]

This conversion How To has it's origins in the Hilux Front Brakes thread from last year. Also in this original thread you will find some good info and the results of my pricing ring-around when sourcing the rotors.
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Last week I ordered the DBA BA Falcon rotors (Cat # DBA504SL + R) from SuperCheap Auto. I picked them up tonight (about $200 with discount).



The specs for these rotors are:

Vented Rotors
298mm diameter
28mm thick
65mm height
71.8mm centre hole
Bolt holes = 5







These rotors will be combined with my Nissan GTS-T R32 4 spot calipers, which I have had for some time, and have been rebuilt with a Nissan kit (genuine $130 from Nissan Australia). Pads were supplied with the calipers (and rotors, which I'm not using here).



I will be putting this kit on the front of my Hilux RN85R using braided brake lines. I'll try and describe the process as best I can.

Cheers,

Peter

[The Real Roadrunner]

you may want to rethink the r32gtst idea and buy some r33gtst ones that will bolt on with these discs. 8mm spacer + longer bolts + new lines and roberts your fathers brother.
may need slight machine of hub and a centre ring.

[infotechplus]

you may want to rethink the r32gtst idea and buy some r33gtst ones that will bolt on with these discs. 8mm spacer + longer bolts + new lines and roberts your fathers brother.
may need slight machine of hub and a centre ring.

Linden, don't tell me I have the wrong set of calipers?

Here they are:



Inside



I've already rebuilt this set. Are they usable?



I'll have to investiage further over the weekend.

Cheers,

Peter

[Screamn_Sleeka]

You definitely have the Aluminium type, so it could be the right or wrong caliper.

Are they like the top or bottom pic?

Top is bad, bottom is good.
There is a 6mm difference in stock rotor thickness, i cant see how the bad caliper could possibly fit over the 296x32mm nissan, but it WILL fit over the 298x28mm falcon rotor - there will just be some wasted rotor surface area

[infotechplus]

You definitely have the Aluminium type, so it could be the right or wrong caliper.Are they like the top or bottom pic?

I have 35mm and test fitted over the BA rotor so all is good on that front. Thanks for that heads-up Screamn_Sleeka. Also the bolt spacing is 100mm which is also correct.

Here is the front passenger side stripped down to the axle:



Plenty of built up grime there and I will have to give it a reasonable scrub with a wire brush to get the disc shield plate off.

Here's a comparsion of the three rotors.Nissan on top, BA Falcon tothe right and the Hilux RN85R to the left.



As the caption says, this photo shows the relative thickness of the Hilux rotor to the BA rotor:



And here's the same comparison, but for the Nissan rotor:



Also compare the thickness of the Hilux and BA rotors, and then the Nissan and BA rotors:





Now here's some comparative figures:

Axle Opening

Hilux 84mm
Nissan R32 68mm
BA Falcon 71.8mm

Pad Contact Area

Hilux 55mm
Nissan R32 56mm
BA Falcon 54mm

Rotor Diameter

Hilux 258mm
Nissan R32 280mm
BA Falcon 298mm

Rotor Thickness

Hilux 25mm (these are used rotors)
Nissan R32 28mm (these are used rotors)
BA Falcon 28mm

Hub Diameter

Hilux 135mm
Nissan R32 155mm
BA Falcon 178mm

Hub Depth

Hilux 22mm
Nissan R32 25mm
BA Falcon 37mm

There are two issues to look at before going any further:

The first is the need to machine out the opening of the BA rotor's axle opening from 71.8mm to take the Hilux hub carrier, which is 84mm. This can be organised without too much fuss.

However ...

The second is fitting the BA rotor to the Hilux hub carrier, the latter being bolted to the original rotor with five 14mm (head) bolts. The Hilux rotor has threaded holes; the BA and Nissan rotors have unthreaded holes (which are also much larger than the Hilux holes). How is this achieved?

Cheers,

Peter

[infotechplus]

OK. I may/may not be able to answer my own two questions here, based on what Linden has said, and what I read in the original thread. People can correct me if I'm wrong.

If I put the original Hilux hub carrier back on the axle (with renewed grease and split pin):



and then put the BA rotor over the studs we have a situation similar to SL666:



I can see what Linden said about a hub spacer now!

Also there seems no need to remove the backing plate as it is well clear of the rotor:



Now when I try the Nissan calipers, whilst the bolt spacing is correct, the BA rotor is too big to allow the caliper to be bolted on.

So I will have to borrow an R33 caliper from my good friends at SSS Automotive and see if that fits.

Cheers,

Peter

[richzx]

Its the diameter of the discs that is the problem. If you use the R32 discs you will be fine but you will need the R33 Calipers to clear the BA discs.

[twentyEight]

Agreed...

You're going to need the R33 Calipers... They look similar, but are smooth on top insteads of being ribbed...

Can be seen here (although not very well): http://cgi.ebay.com.au/NISSAN-SKYLIN...QQcmdZViewItem

[RAd28]

infotechplus - if it's not too late, would you be kind enough to weigh the rotors? i think the callipers are 3.3ish Kg, if you could confirm that too would be great. i'm working on a conversion setup for the celica, would be good to have some numbers like that too.

cheers

[Herus]

Dont mind me im just subscribing

[infotechplus]

I went up to SSS Automotive and got a loaner of the R32GTR/R33GTST caliper. They are the same the boys tell me. And, yes, you will see that mine are ribbed (the red ones) so they are definitely R32GTST. The one I got today is smooth as twentyEight suggests, but looks very similar.

I will have a test fit tomorrow of the R32GTR/R33GTST caliper.

For Rad28 I will weigh both the R32GTST and the R32GTR calipers (without pads). I might also weigh all the rotors whilst I'm at it.

Cheers,

Peter

[infotechplus]

Here are a couple of photos of the R32GTR caliper.

The main difference (to make it easy to tell the R32GTST from the R32GTR) is look at the brake line inlet. On the GTST caliper it's on the right - the R32GTR caliper has it on the left.



Note also the smooth casing on the R32GTR caliper:





Cheers,

Peter

[TheStitt]

how similar is this set up to later model hiluxs Ie my model in my sig??

[The Real Roadrunner]

how similar is this set up to later model hiluxs Ie my model in my sig??

should be the same, i have a complete setup here if you want to test it.

sorry peter,
the leg length is the only difference between the 32 and 33 gtsts but the 32gtr is incorrect for your application also as its meant for a much wider disc (4mm). when the pads get thin it may jam up a piston (not 100% sure but could happen).
i have a set of r33 gtst calipers you can borrow if you want and once you source and rebuild another set just bring mine back.
hope that helps.
cheers
linden

ps peter if you want a full knuckle and hub assy to do it on first i can lend you that too.(keeps your luxxy on the road)

[TheStitt]

should be the same, i have a complete setup here if you want to test it.

Don't tempt me Linden!!!

It doesn't need bigger brakes yet!