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This weekend I'm doing the NA6 to NA8 brake upgrade on my 1990 NA6. The question I have is, will I need an impact driver to remove a screw holding the rotors on, or is the rotor just held on by the wheel lugs/caliper?

I'd check but I'm not able to access the car right now and I've found differing accounts online.

Also throw in any tips you may have about doing the upgrade smoothly.

IIRC not 100% sure (99.99% though)

there is a Philips head bolt holding the rotor onto the bearing. (unless its been removed previously & not replaced.)

you need to remove that bolt.

you need to smash the rotor, preferably with a plastic hammer until it comes off the bearing mount.

if your not worried about the rotor. get any hammer you can find. but wear eye protection while smashing it in the correct direction.
the wheel lugs are part of the bearing.

Obviously the brake caliber & mount/ bracket also need to be removed first

I did the same on a 1989 NA6. Mine didn't have the screw holding the rotor hat to the hub, so it seems that some-do some-don't..

The rotor may be rusted in place after so many years, so although they're only held on by the wheel nuts they can be stuck. An alternative to the hammer method is that there should be a threaded hole (or two?) on the rotor hat that you can screw a bolt into to break the rotor free from the wheel hub. Not as satisfying as a good belt with a hammer, but less dramatic Make sure you clean up the face of the wheel hub so the new rotor can sit properly.

You'll find the NA6 backing plates foul the new bigger rotors, so you'll need to get handy with a pair of pliers to make a bit more space for them.

Since you're going to have to undo the brake lines for the swap over, a bit of gladwrap under the master cylinder cap can slow down the leakage. Cap off, bit of gladwrap over the hole, cap on over the gladwrap. Better if you don't let the system drain dry even if you are changing the fluid as then you'd need to bleed the master cylinder which can be a pain.

There's some recent threads about DIY power bleeding to simplify the fluid change. If you are doing the old pedal-down-hold-pedal-up bleeding, don't allow the pedal to go lower than you would normally brake. Don't push it all the way down to the firewall, or you risk damaging the seals inside the master cylinder.


useful guide.
https://mx5vic.org.au/wp-content/uploads/2013/06/DIY-Brakes-Instructions.pdf

The rotors aren't held on by anything but the wheel clamping down when the nuts are tightened.

Well, by now they'll be held on by rust as well.


To remove rotors you'll either give the face a bash with a rubber hammer, or put a bolt into the threaded hole on the rotor hat.
The threaded hole is there for this reason, as you tighten the bolt it pushes the rotor off (usually it will be tight as before a sudden bang when it breaks the grip of the rust)

The hold has the same thread as he spare wheel tie down bolt, so you can use that if you're strong enough (if you've never done the rotors though you'll need a regular bolt and a spanner to get enough force on to break the grip)

Never had that screw present in 100s of cars I've worked on.

The screw is used on bmws and other Euros. I think it's to stop the rotor holes misalogning with the wheel bolt holes since the Euros refuse to accept lugs as the superior method for wheel fastening.

Sent from my LG-H815