Still trying to find out a cheap way to give 13" rotors to the '84's
#46
The USA "S" brake cars from 82 - 86 are all the same as far as I know. the 78 - 81's have a different spindle, hub, rotor and caliper. Good work Mark, watching the progress with great interest.
#47
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#48
That 35.2mm dim is the Early 944 rotor, it mounts to the back of the hub.
I have read here that the 928 "S" spindles are 89mm caliper bolt centers. I'm tring to confirm the Early 928 spindle ears are 76mm? I've made adapters before that didn't require changing spindles out because Porsche made the spread widths 94mm on the 944 compared to when they went 89mm on the 928 S spindles. There's more than one way to kill a cat.
I have read here that the 928 "S" spindles are 89mm caliper bolt centers. I'm tring to confirm the Early 928 spindle ears are 76mm? I've made adapters before that didn't require changing spindles out because Porsche made the spread widths 94mm on the 944 compared to when they went 89mm on the 928 S spindles. There's more than one way to kill a cat.
#50
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#53
However the conversion I am doing...................err slowly, is GT2/3 2005 calipers = 6 pistons and 355 mm and it uses the EVO 72 vane rally disc. Weighs around 20 pounds plus the alloy hat. I think it is a 32 mm disc as their may be a clearance issue with the thicker disc.
The calipers are $675 each new from Porsche. You can get Pagid pads in any compound too. Annulus of the disc is around 64 mm from memory, I can look it up if needed. The bolt spacing is 142 mm and because of that I think the 80 to 86 spindles can be used.
Greg
#54
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https://www.928gt.com/ps-657-15-big-...77-860998.aspx
#55
So to confirm, the 79-82 spindles have the same AXIAL mounted caliper ears....
and what is the center to center measurement?
The 83-86 "S" are also AXIAL mount and their C2C measurement?
87-up S4, GT, GTS are radial 130mm?
Also according to BigAl1 the 80 Euro S is different?
and what is the center to center measurement?
The 83-86 "S" are also AXIAL mount and their C2C measurement?
87-up S4, GT, GTS are radial 130mm?
Also according to BigAl1 the 80 Euro S is different?
#56
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US 78-81 are the same
US 82-86 are the same
EuroS is the same as US 82-86
Can anyone remember why the "big brake" adapters don't work with the 82-86 spindle? IIRC had something to do with the location of the mounting tabs being lower, putting the caliper right on the ball joint.
US 82-86 are the same
EuroS is the same as US 82-86
Can anyone remember why the "big brake" adapters don't work with the 82-86 spindle? IIRC had something to do with the location of the mounting tabs being lower, putting the caliper right on the ball joint.
#58
Either BJ interference or the radial bolts from the radial calipers interfere with the axial bolts in the brackets. I read from other posts that the "S" spindles were 89mm center to center. A strong adapter bracket can be made with 89mm axial spindles and they would be weaker with 104mm C2C axial throu-bolts (that's assuming you went with 130mm radial calipers).
This was the reason I didn't make adapters for the 86T-944 (94mm).....A porsche afterthought on the front brakes that made the hubs weaker to get the offset for off-the-shelf calipers.
This was the reason I didn't make adapters for the 86T-944 (94mm).....A porsche afterthought on the front brakes that made the hubs weaker to get the offset for off-the-shelf calipers.
#60
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Here is the plan
a flat piece of steel, 9mm thick to mount the calipers to, as well as to the spindle.
any pictures of the calipers themselves. I forgot what they look like, to see if a flat plate will work or get in the way of mounting.
a flat piece of steel, 9mm thick to mount the calipers to, as well as to the spindle.
any pictures of the calipers themselves. I forgot what they look like, to see if a flat plate will work or get in the way of mounting.