Bigger disks with nothing else?

5uprahboy

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Aug 22, 2005
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Hey all

Is it possible to put bigger disks on, without doing anything else? Maybe just changing pads?

Basically I'm asking, can you use the stock calipers (with adapters) on bigger rotors?
 

GrimJack

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Dec 31, 1969
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Sure, but two things come to mind.

1. The adapters aren't going to be simple.
2. Why would you want to? The extra rotor size isn't going to help. You can already trigger the antilock system with the stock size rotors, so the extra braking power means diddly. And you are still using the same brake pad size, caliper, etc, so it will have the same problems with heat soak at the same point, no benefit there either.
 

IJ.

Grumpy Old Man
Mar 30, 2005
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I come from a land down under
Bit of added leverage and bit less fade due to increased mass and unless you change the rears are well you're upsetting the front to rear bias... (something that doesn't seem to concern most here)
 

Mo87NA

1987 7M-GE & 1991 7M-GTE
Mar 31, 2005
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5uprahboy;1288469 said:
Bigger disks with nothing else?

I must be a little hungover, but I definitely read that incorrectly lol. :nono:

On a side note, listen to IJ and Grimjack, they're smart :biglaugh:
 

87tomanymods

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i wouldnt bother more trouble than its worth . try an auto cross brake pad the ebc greens are great and maby braided hoses .these are two cheap upgrades that i beleive will net more stoping power than just bigger rotors. ps. the mk3 already has pretty big rotors , the weak link is the calipers with their single piston design
 

adampecush

Regular Supramaniac
May 11, 2006
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the weak link is the lack of mass available to absorb heat due to repeated stops. The lack of cooling doesn't help either.
 

Doward

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Jan 11, 2006
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IJ.;1288475 said:
Bit of added leverage and bit less fade due to increased mass and unless you change the rears are well you're upsetting the front to rear bias... (something that doesn't seem to concern most here)

That's the truth - Jeff took out the prototype setup to an AutoX, and the rears can't even begin to keep up with the fronts any more.

I'm going to have to address that little problem.
 

Poodles

I play with fire
Jul 22, 2006
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IJ: true, but if your car has ABS brake bias is adjusted on the fly anyway...

As it is, adam is right, there isn't enough mass and you'll quickly boil the brake fluid on a fast course.

The stock brakes are good enough to stop from over 100MPH.......once.
 

tekdeus

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Jan 23, 2006
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Doward;1288677 said:
That's the truth - Jeff took out the prototype setup to an AutoX, and the rears can't even begin to keep up with the fronts any more. I'm going to have to address that little problem.
I'll be running Mk4 TT dual piston rear brakes. With a little luck, it might match up well!
 

adampecush

Regular Supramaniac
May 11, 2006
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tekdeus;1288754 said:
I'll be running Mk4 TT dual piston rear brakes. With a little luck, it might match up well!

I'll let you know how it matches in a few weeks.(arz front)
p1288788_1.jpg
 

5uprahboy

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Aug 22, 2005
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I have mintex 1166 pads already. I just don't have a whole lot of faith in the stock disks ability to dissipate enough heat when I jump on the picks at the end of the straight doing 145-150mph......
 

prsrcokr

Motörhead
Apr 3, 2005
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IJ.;1288475 said:
Bit of added leverage and bit less fade due to increased mass and unless you change the rears are well you're upsetting the front to rear bias... (something that doesn't seem to concern most here)

Most haven't tried threshold braking heading downhill with an unbiased setup ;)

I see you're idea OP and it works on some cars, but you'd be adding mass (not good, stock is already heavy stuff) With some you can get a thicker rotor that's two piece and actually lighter than stock. I don't think it would work with a sliding setup like ours. Again, I'll say the stock brakes aren't bad with good pads (E46 M3's have a single piston) but it would be nice to have something that's lighter and cools better.
A two piece OEM fitment rotor would be a great option if the outer were reasonbly priced. I wonder if someone could make those?

You could run a different compound in the rear if you've got that much more front bias now or get a bias controller to help balance it.
Brian
 

Supra-Man18

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Nov 24, 2007
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Poodles;1288743 said:
IJ: true, but if your car has ABS brake bias is adjusted on the fly anyway...

As it is, adam is right, there isn't enough mass and you'll quickly boil the brake fluid on a fast course.

The stock brakes are good enough to stop from over 100MPH.......once.


LMAO Once And jus once !:sarcasm:
 

prsrcokr

Motörhead
Apr 3, 2005
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Same front rear/widths 1J? I wonder if my wider rears make those pads wear less quickly? I'm sure you're seeing much higher speeds than me, longer stretches and you've got more power (I'm probably 300-320 bhp, maybe 270-80 whp?)

FWIW, I don't even use the fancy fluids just good, purpose intended pads. I don't get fade with SS lines, plain rotors, dust shields still in tact, stock calipers. I've only been on street tires so far so cornering speed and max will be higher with stickier stuff but also braking distance (and subsequently heat) would be reduced or roughly the same. I'll probably switch to a better fluid since Valvoline changed their formula and I'm now out of my stockpile of it (blue bottle has signifigantly lower dry & wet BP)

Anyone know if the two piece rotor has ever been looked into? Seems like a good option to me.
 

IJ.

Grumpy Old Man
Mar 30, 2005
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I come from a land down under
265 front 285 rear DBA 5000 Mk4TT fronts and dba 4000 Mk4 rears AP calipers front and rear.

I generate enough Temp on the rears to colour the entire discs (this was after 55 turns averaging .7G lateral per turn and moderate braking for each corner)