aribop

Size wise, yes, but the piston diameters are smaller than the front calipers.

Serge944

Considering the n/a brakes aren't "small" and the standard 951 brakes are pretty big, even by todays standards - that's pretty impressive. The brakes on 951s and such really make them stand out from other cars in this category, IMO.

Come to think of it, brakes are probably the largest drawback on my e30, but I'm getting by with race pads and blue fluid.

NineFourFourNeophyte

oh,

so if i ever consider upgrading to turbo calipers, then i need more than just the calipers. darn. ok

thanks.

944Fest (aka Dan P)

..meaning that IF I put Turbo S rears on the front of an 88 n/a with Turbo Spindles/hubs/rotors they would fit but it would take extra/excessive pedal pressure to activate them?

strandolph

Why won't it work? Or, more specifically, what part won't work? At this point, I'm thinking that the "finding a rotor" part won't work.

The offset is a function of the A-arms, Right? (although the spindles are different--have shock mounts angled specifically for the offset, and of course the hats are different) So the Kokeln hats should be made with an offset that's correct for a late model A-arm. What else is there besides bolt hole pattern, offset, and rotor mount configuration? Unless the actual hat diameter is different. Or the the M030 spindles require a slightly different offset in the rotor hat than a standard late-model spindle. But, if the offset is correct, the bolt holes are correct, the only thing left to solve is find a rotor that'll bolt to the hat and work with an NA late-model brake setup...

aribop

No. Since the piston diameters are smaller, they won't exert as much force on the rotor as if you had the front calipers there with larger piston diameters. However, the rears on the front will brake better than the regular n/a brakes. You may end up having to play with the proportioning valves to get the braking bias correctly adjusted.

aribop

See here: https://rennlist.com/forums/924-931-944-951-968-forum/257774-educational-post-3-a.html

The Kokeln hats are made to take care of that bit of difference in the offset of the MO30 hub verses the stock 951 hub. Using a regular 993TT rotor on the MO30 hubs will not center the rotor with the caliper, thus necessitating the use of the aluminum hats. Also I do not know of a two-pice rotor that is made whose diameter matches the diameter of the regular 951 rotor. Good luck in your search!

strandolph

Ahh, thanks for that bit of illumination. I figured that, when I get serious about my search, I'd take some measurements of a stock rotor and make phone calls among the various manufacturers to see what I can find.

Steve

944Fest (aka Dan P)

Slightly confused.. You started your post with a "No", yet it seems this description would describe what I asked?

aribop

Sorry, Dan. No is the response to the question of taking extra pedal effort. I doubt you will be able to tell the difference....unless you remove the power brake booster.

FRporscheman

Thanks Tifo, I learned something today.

That pic really makes the 968/951 caliper look small, but in reality it is relatively large. And I agree with Serge, the brakes (at least on the 968/951) were fantastic, and still are, especially compared to other cars from the same era.

I was told the 968 uses the exact same calipers for the front and rear. I know for a fact the same pads work on front and rear.

Techno Duck

The pads are the same, though the piston sizes are slightly smaller in the rear and the mounting holes are spaced a bit differently.

944Fest (aka Dan P)

OK, now I'm honestly more confused. It sounds like a smaller piston would exert less force. (100 psi on 1 square inch vs. 100 psi on 1.5 square inches is a large difference!!) As I would expect, but is it a 100% difference or just 10 or 20%? Has anyone actually done what I am planning?
I take it you mean I'll be OK, but not up to 100% capability of that "sized" caliper?

Thanks for the clarification.

tifosiman

Dan, the rears have slightly different mounting holes when compared to the fronts, so they do not bolt up to the 951 spindle or the 944 spindle. The 951 rears are a direct bolt on to the 944 rear mountpoints though with the longer bolts and proper spacers/washers.

Olli Snellman

Here's several calipers compared to 951 "baby Brembo"