Brake Upgrade Information

I've got slotted/dimpled RDA rear discs on mine, they seem perfectly fine.
Done over a year of daily duties and 8 motorkhana's ripping the hand brake on them since.
I'm pretty happy with them so far.
 
Rotor is a basically a heatsink. If something was uneven you would have larger and far more obvious problems exhibiting first!

As for bias valve, be careful how approach this. Just be prepared for the possibility to upgrade yoir master cylinder as well. Use all the parts from the same car to keep it balanced thw way it should.

I have used the same ARC... cant complain at all. Not a fan of drilled rotors due to cracking out over time.
 
Guys I know I've brought this up before but never had a conclusive answer...
The brake bias/prop valve on cars with drum brakes seems to be inefficient once going to disc brakes.
My bias was 91/9 after doing the disc conversion.
Has anyone checked what other prop valves would fix up the bias closer to 70/30?
Currently due to availability I'll be looking at some FTO ones but unsure whether auto/manual and ABS/non-ABS makes a difference?

If i recall correctly, the prop valve is the same between CE, FTO, Magna, and Evo. I cant remember who found this info, but the part numbers were all the same
 
Does anyone know if a brake shop can test a bias on the prop valve or what kind of shop can perform such a test?

I have a 7/8" BMC but will be upgrading to 15/16". I was considering the 1" but without ABS I am concerned of accidentally locking up the wheels.
The 15/16" BMC is from a non-ABS equipped FTO and I hopefully will get the prop valve from that as well
 
I do know that pedders suspension places have the ability to test susoension and also individual braking capacity of each corner.

Im sure there are others as well but thats all that comes to mind atm. As far as a bigger BMC goes you just dont have to press as hard on the pedal as you normally did. All it does is pump more fluid through your lines. Stick with some decent rubber on your rims and everything will be all good... lo

Pun not intended :laughing:
 
Yeah I understand that less pedal travel will result in the same or more braking force. The ease (or assistance) of the pedal travel will be determined by the booster size.
I'll see how I go but without ABS it seems that a longer more progressive brake pedal might be the way to go
 
Progressive comes with correct adjustment. Just the pedal travel changes. I upgraded my brakes on my 180sx that had an ls1 in it with gtr brakes and upgraded bmc and slave. No abs. Bit like a starving croc but fantastic once i got used to it...
 
If you are upgrading the brake size with the BMC it will be quite hard to lock up the big brakes in general, and even if you manage to do so, you'll be stopping pretty damn quickly regardless due to them. I would also suggest driving more cautiously for the first week of a new brake setup so that you get used to the feel of it, because that will impact you in regards to not locking up more than ABS ever will.

tl;dr do a brake upgrade with the BMC upgrade. If you already have the brake upgrade, get the 1" booster and learn the new feel of your pedal over time.
 
Thanks guys,
I've read some people report that 1" is too large without ABS (too stiff of a feel through the pedal).
Also there twin piston front calipers come with 2 different piston sizes which in theory should equate to the opposite effect of the BMC, ie, mine are the smaller version (4304 casting, banjo fitting) which should equate to a similar feel of a larger BMC. Though the difference in diameter is only a couple of mm and the piston travel onto the brakes is near minimal so I am not sure if there is any real life difference in feel between the two calipers.

I think my 7/8th of an inch BMC is a bit small though currently.
There are also a fair few different sized brake boosters which can be changed over if brakes are locking up too easily.

Without having driven the car yet though this is all a bit too speculative and I'll be tracking data on my first drive and will see what adjustments I will be making to get everything feeling just right
 
4304 are the larger pistons. 4304 are evo123/fto mivec. 2207 are on as far as i can tell some galants and magnas and eclipses as well as some overseas models of 3000gt's/diamontes etc but can also have the casting 2311. But the 4304 is the largest.

My upgrade is a 2207 cast (which is the same casting number as the brackets that all mentioned above use)

Even then... the piston size is 1~2mm difference.

What stud pattern will you be running? if you have converted to 5x114 you can always go bigger and get an outlander bracket and get dba 417s which are 294mm.

This would also take you away from worry of the mini cooper rotor min thickness as these are the same as normal thickness which is 24mm/22.4mm.

I might be doing this once my rotors need changing but going the 294mm cooper setup as im not fussed about the min thickness issue and they are still 4x100 and 64mm centre.
 
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42mm piston on the 2207 casting.
43mm piston on the 4304 casting.
43mm piston on the 2311 casting.

The 2311 was found on diamonte/3000gt
The 4304 is found on many thing from evo123/fto mivecs/outlander/galants/spacerunners/lancer sportsback RAs etc etc
The 2207 are on eclipses and magnas.

I have a whole butt tonne of info on the calipers withc picture and oem part numbers which im organising to post up.
 
I followed what the guy in this link found and it seemed that the 4304 castings were the small pistons?
http://ayu452.blogspot.com.au/2013/11/evo-iii-caliper-rebuild-vr4-galant-42mm.html

Either way I am rebuilding the brakes all round (the front calipers are at the sandblaster shop now).

I'm running 4X100 PCD and will be getting the DBA 4000 series rotors for the Evo III redrilled to that + running hubcentric rings.
Pads will be Forza FP3 and Motul Racing 6600 fluid.
This should already be more than enough for the car and I doubt I will have any fade issues.

I'm not going the 294mm rotors as this will mean I need to run 16" wheels which I do not want as this will make the car slower overall and there are fewer racing tyres options.

If I find my brakes are insufficient (highly unlikely) I will try to adapt the 380 brakes as they are considerably thicker rotors + the caliper is aluminum so they weigh less overall which will not mean I am going backwards in every department other than braking.

Do post your findings and pics though as it would really help in this thread
 
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Thats understandable. But yeah i dont think he was right about the piston size. He said yet to confirm on the post. But from my research you have the largest.
 
But from my research you have the largest.

Thanks ;)


I'll measure my pistons up and see what they are. I ended up going the brake rebuild part number that he provided in that link and not the one listed for the FTO so hopefully it is the right one
 
I compared the old seals that came out of the caliper to the rebuild kit and it all looked good to me but of course at 1mm difference perhaps I just didn't notice it.

Either way not a huge problem as I'll just order the other kit
 
Well which kit did u get? Give what you got a go first before ordering what i suggested.
 
I have the MB699456 seal kit which is what the guy used in that link for his 4304 calipers.
Will I even know if it is the right or wrong seal kit? As the difference is 1-2mm and if I got the smaller seal kit but larger pistons wouldn't the rubber just stretch?

My pistons are at the brake shop being micropolished and the calipers sandblasted but once I get them back I will dummy fit the seal kit to see whether I need the MB857840 seal kit instead
 
Yeah. No worries his post is very confusing. Because in another post he had a picture of a 2311 cast calliper and even wrote that he had used a 2311 (smaller piston) but in the post your refering to he shows a picture of a 4304 (larger piston) cast. Maybe he uploaded wrong picture? I dunno lol.

*EDIT*

Its also entirely plausible that he got the 4304 castings from a car that had new pistons installed from the 42mm pistons because from what i can tell the bore diameter is the same across all 3 castings and technically you can put in any variation of pistons as long as you use the right sealing kits.
 
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It is easy to know which you need without pulling it apart.
vr4 galant 276mm which have the inverted flare are all small pistons.
Any twin piston with banjo will have larger pistons.
Easy as.
You cannot stretch rubber seals or piston dust boots. They need to seat in the groove properly.
I can supply the correct OVERHAUL REBUILD kit. Ive rebuilt all types of the twin piston caliper.

I have some in stock.

I also do custom hubcentric rings when you use EVO 1-4 rotors with 69mm bore.
 
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