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What Rotors Do I Have?

Samon
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Samon

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Hi Guys,

The brakes on my 33 GTS have been squeeking a bit lately, so today I decided to pull a wheel or two off and have a look at them. Popped the front wheel off, took off the caliper and pads, took off the rotor and measured the thickness with a micrometer. It was 21.3mm. I have looked at the DBA Catalogue but can't find the specs for an R33 non-turbo. Not 100% sure why (I believe it's because I have an LSD, but not really sure) but I have 5 wheel studs... even though it's a non-turbo... meh anyway the GTST is specified as having a 28mm minimum thickness on the front rotors... this means that either my rotors are 6.7mm under the minimum, or I have totally different brakes.

After finding this I decided to take a look at the rears. I pulled the wheel off, took off the caliper, but couldn't manage to get the rotor off... anyway i again measured with the micrometer and found that these were 8.6mm thick. The DBA Catalogue specifies 16mm as the minimum for the R33 GTST, so again either my rotors are MASSIVLY undersize (by 7.4mm) or are not the correct discs. I also noted (not sure if this is normal or not) that while the front discs were ventilated, the rears were solid.

Basically what I want to know is what the specs are for the new/minimum thicknesses for the R33 GTS, and is it that my brakes are massively undersize or off a totally different car?

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Samon Proficient

Samon

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Not really sure if it means anything, but I also noted that I have twin-piston calipers on the front and single-piston calipers on the rear. Everything looks pretty standard under there.

Samon Proficient

Samon

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After looking through my R33 ENGINE SERVICE MANUAL that i bought off eBay, i found that there are two specifications for front-brakes: 20mm minimum for the single-pot calipers, and 24mm minimum for the twin-pot ones. For the rears it specifies an 8mm minimum.

I am rather confused. Where did DBA get the 28mm and 16mm from? Also, my rears are within the nissan specs, but my fronts are within the specs for the single-pot, even though it has twin-pots. From looking at my front rotors it is extremely hard to believe that they were EVER the 26mm that the manual specifies for the standard thickness for the twin-pot calipers, so I think I will just leave it all as is and see how it goes. I certainly have no problems stopping, and haven't noticed any brake fade occurring, so i think it's alright.

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