Twin piston brake upgrade: Cressida strut MPV rotor R34GT caliper help!

[random]

Hi guys,

Just discussing my attempts at a brake upgrade so far. Need some ideas!

I want bigger brakes but don't want four piston calipers needing wheel spacers or wheels with lots of 'x-factor' etc. So thought I'd do a twin piston upgrade instead.

I've read about using a Mazda MPV rotor with R34 GT non turbo twin piston sliding calipers. AndrewMX83 discovered this and had written about it on the old aussie cressida forum.

So, I got the 276mm discs (RDA960), redrilled to 4 stud, had hubs turned down to fit disks over

Found someone wrecking what they said was an R34 GT and got the front calipers. They suit a 280mm disc and have 14mm mounting bolts.

And now to my problem: Calipers didn't fit - disk needs spacing out 3ish mm from the hub to be centred in the caliper.

So picked up a set of twin pots from a A32? maxima. These suit a 290mm disc (which I didn't know at the time), and have 12mm mounting bolts.

Tried to bolt them up and they also are offset by the same 3ish mm (and my 280mm discs are too small anyway (pad sits out from the disc by 4-5mm.

What should I do?

Couple of options I can think of:

Space current out discs to fit R34GT calipers?
Buy some Z32/R32 four pots which are known to suit my already modified MPV discs & hunting for go a new set of wheels to suit?
Buy new 287mm AU falcon discs, space them out 3mm and use the maxima twin pots?
Buy new 298mm BA falcon discs, and get some R33 four pots?

Or am I missing something blindingly obvious that's causing my disc-offset issue?

School me!

[allencr]

Space current out discs to fit R34GT calipers or space caliper to fit disk?
Buy some Z32/R32 four pots which are known to suit my already modified MPV discs & hunting for go a new set of wheels to suit?
Buy new 287mm AU falcon discs, space them out 3mm and use the maxima twin pots?
Buy new 298mm BA falcon discs, and get some R33 four pots?

Fixed .


.

[random]

Nah, I would have to remove 3mm from caliper mount to get it to fit. What am I doing wrong?

[masterofsinanju]

Customs hubs with more space?

Just get a caliper bracket made up to adjust the spacing needed?

[random]

Maybe. I don't understand what's going wrong. AndrewMX83 used the R34 callipers and MPV rotors and it worked for him fine (on an MX83).
So if I go and buy Z32/R32 four pots am I going to have the same issue with them not fitting?
This is on an RA65 strut with an MX73 (I think) hub.
I thought MX73 & RA65 hubs were identical.

[andrew_mx83]

you mentioned redrilling to 4 stud so i assume you're doing this to an mx73, which is probably why it doesnt work.

actually the z32/r32 4 pots with mpv rotors may work out well for you, as on an mx83 the rotors sit out 3mm too far. some people fix this by running a spacer under the caliper however i just machine 3mm off the inside of the rotor mounting face, as those mpv rotors are quite thick there and that brings it all back to being centralised.

if you wanted to persist with the twin pots on 73 struts, id either look at getting the 3mm machined off the caliper mounting legs, or hub mounting face if there is enough meat. otherwise a simple slip on spacer under the rotor would work too and probably be easier.

or just stick mx83 front suspension in it, pretty sure it all bolts striaght in, then you have 5 stud and a number of proven brake upgrades (like the 34 twin spot/mpv combo which does work fine, im rocking these currently and they are pretty good.)

[andrew_mx83]

oops, missed your last post. thats yer problem right there

[random]

Thank you! So I'm not going crazy! Now I can decide which option to take.

[random]

Seeing as though I have already:

bought MPV discs & had them re-drilled to four stud
installed longer wheel studs into hubs
shortened & added coilover sleeves to RA65 struts
RA65 PS steering arms with enlarged BJ taper

I think I'll just buy some Z32/R32 four pots and put up with having to buy some new wheels.