im going to make it!

just need to verify the bolt spacing and diameter differences to make the plate.

mk

 

are the caliper bolts the same as the S4? (pitch, diameter, etc)
anyone have a picture of a caliper for me.
I might be able to do this without a mock up, if I can see good pictures.
24mm standoff, 9mm thickness, but I need the confirmation of the threaded bolts, lenght of those bolts, etc
I think we need to visit scot to do a mock up.

 

LOL....Geeks "r" Us.

What is the weight of a 322mm dia. 928GTS rotor?
The 318mm dia BoxsterS rotors that I have/weighed are 17.72 Lbs.
I have the info on my flash drive of which WW hats I would mod to fit the late 944 hubs and from all the posts I've seen from you guys, the late 944 hubs are the same as the 928 later hubs, but I'm not sure of the Early 928 hubs.

 

Question on the side:

Is this PURELY to get a bigger brake disc?? Or are we also talking new calipers?

 

4x42 monoblocks hehe?
Do the Porsche calipers have dowel pins?
I updated the bracket design to get more meat around the dowels when I went to a billet T6061-T6 alloy.

 

Steel! The addapler is going to be taking the full load of stopping the wheel. Expectant with larger tires the load posed on the caliper will increase. Plus this is brake component so for safety it's not worth the reduction in weight to go to aluminum.

 

purely for larger discs, because that is really what only matters in racing.
(besides the heat dissipation, etc qualities) sure, the bigger calipers are better, smoother, more even clamping force, but for a budget upgrade to tremendously help the '84 brakes, this is the way to go.

ONE PROBLEM> new discs I discovered from VW /porsche, are only 27mm thick. not a huge issue, but an issue none the less.

one quick check will solve this issue, checking if any BMWs had 27mm rotor thickness. Its only our rotors go from 32mm down to the limits of 30mm. 27mm wouldnt be that much differnent. I would worry about warping, but heck, its SO much larger than the stock stuff, it might be ok
thoughts?

next question, lets find another porsche rotor with the same overall thickness
(i.e. 69mm) (vs the S4 80mm and the '84 60mm)

mk

 

stop confusing us with the 944 stuff .

the GTS rotor is about 20lbs, but Ill check. the s4 was around 17lbs too.

what are the offsets of the boxter S rotors?? If they are near what we are looking at, we can possibly use them, but I dont think they are.

i think the offsets for the boxster S rotors are way off.

let me know!

mk

 

These adapters will be a little more complex than the axial to radial adapters. These will need to be machined with a step in them that allows them to bolt to the outside of the upright and then jog inboard so the caliper can bolt to the outside of the adapter, something similar to the style of this one. This is a mountain bike brake adapter but the general design will be similar.

 

I can build anything. I chose the BoxsterS rotors not only for the lighter weight and INEXPENSIVE, but the offset is 67.2mm and the rotor thickness is 28mm also...
My mic doesn't lie.....

 

Not sure about 928, but on the Late 944 Hubs/spindles you can safely go to an
82mm offset before the inner rotor sweep touches the knuckle, probably more because I measured off my large dia. bump steer bolt I made....
Since I have no doubt the BoxsterS rotors would be an excellent upgrade to the Early 928 and the 928 hubcentric 71.6mm is the same as the 944 hubs....The centering rings would be the same damn dimensions.....



No Vibes at 150mph either LOL.....

 

You could always go with GT3 rotors if your woried about thickness.

 

So what are the spindle/caliper bolt hole center to centers on the 84?

 

the offset is what dictates what rotor can be used. i guess if you are talking all using adapters, to correct the offset, then yes, you are right.

I dont know about the "82mm" offset being ok on the early cars, as most have tried the 80mm range S4 rotors and they hit the tie rod end.

The trick is to find a rotor that has an offset that is enough to make room for a .25 to .5" spacer that would be drilled and tapped. for moving the caliper outward, and inward.

the hubcentric part is not the part that opens up for the bearing caps, that surface is not used. it can be big or small as long as its big enough for the bearing cap to poke through. the hubcentric part is on the inside of the rotor, that makes contact to the hub stud carrier surface.

I dont think the OB's (early 928s) and the 84 year 928s share the same rotor offset, right??

 

the problem for boxster S is that you only have 7.2 vs 9mm to work with on spacer thickness.
the other issue is that it is only 318mm, vs the 330mm Im working with. Glad to see all those comparisons. looks like 32-30mm down to 28mm is a non issue, as many of these cars have this thin of a rotor. thats good.

talk about cheap, YOU could then use the VW rotor 330mm and have everything the same, but the diameter being 330mm. (13"). they are cheap too.

what is that 35.2mm dimension on the 944 rotor? wow, they use only 20mm thickness rotors??

as a note, it looks like the late model 944turbo is the same rotor as the 928s4, correct? 77.3 offset?