993T Calipers on 944T Rotors?

[vujade]

Lanner

I have access to a set of 993T calipers and was told by the guy selling
them that they would also work on 944T rotors... is this true?

I would love to have a set of those big reds for my 944T brakes on my 1303

[flat]

The 993T uses rotors that measure 322x32F, 322x28R.

The regular 944T 298x28F, 299x24R.

The 944T S (M758 option) has 304x32F, 299x24R.

So if you use the 993T front calipers on the 944T S front rotors, you will have no problem. There may be a small issue with the clearancing the pad because of the diametral difference in the rotors. Tough to say, it's not that much (18mm, 9mm on radius). Worst case would be a little clearancing of the outer pad it it interferes with the hub.

I wouldn't recommend using those calipers on the regular 944T rotors, because you have the potential of overextending the caliper pistons. You can get away with it, but you have to really watch your pad thickness. You'd have to replace the pads at about when they wear down to about 80-75% of new thickness. The pad 'slider' in the caliper is only so long, and you can pop the pad off the slider if it wears down. In general, it's too much to worry about in my opinion.

If you have the 87+ 944 hubs, then the 944NA, 944T and 944T S rotors will interchange on the same hub.

Easy,
Lanner

[vujade]

thanks Lanner, on that note, will the 944T S rotors increase the front
track more then the regular 944T rotors?

[flat]

No,
The mouting thickness of the rotor (where the wheel bolts on) is the same for all the late model 944's. So the offset increase is determined the hub. Using modified late model 944 hubs, I can keep the offset increase to about 2-3mm per side. This doesn't leave much room for a bolt on caliper bracket, hence the spindle requires machining for the caliper bracket to be attached to the rear face of the spindle.

Easy,
Lanner.

[vujade]

thanks Lanner!

I will call you as soon as I have all the parts I need :D