belize1334
Well-known member
I've spent the last day or so searching for rotors that have the same total height and discard thickness as our stock rotors (front and rear) with the idea that they could be used in an OEM big brake kit where the stock calipers are retained but used with larger rotors and new brackets. I came across a few interesting things.
For reference, the dimensions of the stock rotors are:
Front:
diameter - 10.86"
height - 1.77"
thickness - 0.886"
Rear
diameter - 10.45"
height - 1.94"
thickness - 0.33"
Now, the rears are the real headache since they need to be solid but with a relatively low height since they don't have an incorporated drum. The only thing that even comes close is from an Audi A6.
A6 rears:
diameter 11.88"
height - 1.934
thickness - 0.393"
Now, obviously the bolt pattern will be wrong so I assume the need to drill a new pattern. But, aside from being slightly too thick it's a pretty good match with a diameter upgrade of about 14%. I don't know if the added 0.063" will fit down into the caliper gap but I assume that if not it could be "resurfaced" down to the appropriate thickness.
For the fronts we're looking for something in the 12.3" range to keep the bias the same as stock. I thought it would be easy but it turns out that our fronts are relatively thin for their size and I was getting discouraged by all the options that weren't QUITE right. Until, I found the 2004 Montero Sport
04 Montero w/ 16" wheels:
diameter - 12.365"
height - 1.78"
thickness - 0.882"
Whats even better is that the images of the caliper for that car look identical to ours (rockauto.com) but with a different bracket. It may be a direct swap for the front as opposed to a "make a bracket" deal for the rears. But, what has me concerned is the "L mounting type" vs. "K mounting type" that most cars see. Is that just a distinction between car and truck (with the larger center bore)? The bolt pattern is 4.25" so it should have room to accomodate a 114.3mm pattern and a spacer disc to make it hub-centric.
The other option that I found is the rear from an Audi A8
A8 rear:
diameter - 12.2"
height - 1.66"
thickness - 0.787"
Now, that's about 0.1" thinner than our calipers and also about 0.1" shorter so it'd mean that the piston would be further extended to make the pad contact but the rotor should fit inside the caliper with stock mounting position (laterally). I don't know if the reduced thickness will have a big effect on performance.
The last option is 3000gt front rotors (2G) which are perfect in diameter and height but are 1.15" thick instead of 0.886". I doubt they'd fit as are and I don't think it wise to machine down a vented rotor or it could be unsound... Does anyone know how wide the stock calipers can be pushed? It is possible that they would accommodate a 1.1" rotor as is?
For reference, the dimensions of the stock rotors are:
Front:
diameter - 10.86"
height - 1.77"
thickness - 0.886"
Rear
diameter - 10.45"
height - 1.94"
thickness - 0.33"
Now, the rears are the real headache since they need to be solid but with a relatively low height since they don't have an incorporated drum. The only thing that even comes close is from an Audi A6.
A6 rears:
diameter 11.88"
height - 1.934
thickness - 0.393"
Now, obviously the bolt pattern will be wrong so I assume the need to drill a new pattern. But, aside from being slightly too thick it's a pretty good match with a diameter upgrade of about 14%. I don't know if the added 0.063" will fit down into the caliper gap but I assume that if not it could be "resurfaced" down to the appropriate thickness.
For the fronts we're looking for something in the 12.3" range to keep the bias the same as stock. I thought it would be easy but it turns out that our fronts are relatively thin for their size and I was getting discouraged by all the options that weren't QUITE right. Until, I found the 2004 Montero Sport
04 Montero w/ 16" wheels:
diameter - 12.365"
height - 1.78"
thickness - 0.882"
Whats even better is that the images of the caliper for that car look identical to ours (rockauto.com) but with a different bracket. It may be a direct swap for the front as opposed to a "make a bracket" deal for the rears. But, what has me concerned is the "L mounting type" vs. "K mounting type" that most cars see. Is that just a distinction between car and truck (with the larger center bore)? The bolt pattern is 4.25" so it should have room to accomodate a 114.3mm pattern and a spacer disc to make it hub-centric.
The other option that I found is the rear from an Audi A8
A8 rear:
diameter - 12.2"
height - 1.66"
thickness - 0.787"
Now, that's about 0.1" thinner than our calipers and also about 0.1" shorter so it'd mean that the piston would be further extended to make the pad contact but the rotor should fit inside the caliper with stock mounting position (laterally). I don't know if the reduced thickness will have a big effect on performance.
The last option is 3000gt front rotors (2G) which are perfect in diameter and height but are 1.15" thick instead of 0.886". I doubt they'd fit as are and I don't think it wise to machine down a vented rotor or it could be unsound... Does anyone know how wide the stock calipers can be pushed? It is possible that they would accommodate a 1.1" rotor as is?
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