Not your typical mix and match question...you will be graded

[speedo]

Ok...so the front suspension on my 71 targa has been swapped out for an earlier 3 bolt SWB strut, A-arm, crossmember setup. Aside from the multiple pieces...I don't have a problem with the earlier configuration...with the exception that the brakes are the smaller pre-M brakes and solid rotors. Now the problem comes with the rear of the car wearing the stock M rotors for 71 with vented rotors. Theoretically...the better brakes need to be up front, and in my case...the opposite is true. The easiest thing for me to do is to drop the SWB front suspension, and simply replace with an SC strut-A arm-alum cross member setup. I have the crossmember, and A arms, so all I need to do is source some struts (with rotors and calipers) and bolt things up. However...I stumbled across a Pelican with dual piston Boxster brakes and the adapters to convert 3" spacing to 3.5" spacing to utilize the Boxster brakes. Typically the adapters are used on 3" struts which use the vented rotors...70-73 maybe? Will I end up with an engineering nightmare if I attempt to used the later vented rotors on the 3 bolt SWB struts with the adapters and Boxster brakes? Or to simplify things...can I use the vented rotors on the 3 bolt SWB Koni struts with M calipers? If the answer to both of the questions above is negative....and you have some SC struts for sale...please PM me.
Thanks guys...

Speedo

[AVDCAV]

I'm gonna just wait for jw to answer
And just agree, this way I pass.

Did it in school worked out great ""

[speedo]

This can't be that tough of a question. And I am pretty sure that PET is going to be of little help. If I don't get the right answer shortly...I'm going to fail the whole class

Speedo

[304065]

Lemme get this straight, you want to use the SWB caliper plates with an adapter plate on that?

That won't work.

If you want to mount big brakes to the SWB struts you should custom fab a plate to go between the four bolts on the spindle and the 3.5" ears.

HOWEVER, the SWB design is inferior to the later design. The ball joints are $200 each. The rear bushings are $250 each. The adjustability is a lot less and the whole assembly weighs a lot more. It is a no-brainer to switch to a Carrera front setup.

Cool factor aside, do you really need boxster brakes? It's not so much the calipers as it is the rotor mass that is the limiting factor, I bet you can lock them up just fine with something from the 1980s. What does the car weigh, 2300 pounds?

[tadd]

Ummm... both SWB and early LWB use 280 mm diameter disks. So the 'stopping power' should be identical. What is the big difference is the thermal capacity of the rotor- how many times you can stop hard.

The SWB cars use either solid or vented. Difference was a spacer added between the two caliper halves AND the hub got thinner to make up for the 7mm disk thickness that was added by the vented rotors.

The next LWB upgrade was to 300 mm disks upfront (310 rear). Still with the same aluminum S caliper. This was carried up to the first turbo with floating 300 mm disks.

If you want ALOT more brake under a 15" rim, go with the 930 setup and you will need new struts to get the 3.5" caliper mount.

If you just want more brake, Enough to hurt yourself on the seatbelt, Then add the vented disk up front with S calipers or go with these (!). A bolt on for the 3" spacing and are lighter to boot.

Brembo AM-Caliper: The "ULTIMATE" M-Caliper Up-Grade!!

Use a good fluid and a soft street pad. More stop than you can shake a stick at.

BTW, early ball joints are a bit pricy, but you only need to change them every 30 years... Nothing truly wrong with the SWB suspension. One huge advantage the early SWB cars have is the REBUILDABLE struts. Pour out the old oil, add new.

I've been told that even the 'evil' rear suspension can be made as good as the LWB without actually making them longer. Porsche was just a bit skimpy with material in the bananas.

tadd

[speedo]

That is exactly what I wanted to hear. Didn't know about the spacer trick on the SWB calipers to use the vented rotor. I don't need massive stopping power...just more braking authority (bias) in the front than in the rear. Judging from what I learned...the SC-Carrera strut upgrade is the path of least resistance.

I appreciate the responses. Great to have the board as a resource.

Speedo