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chriso · Joined: 23 Dec 2002 Posts: 36 Location: Lincoln Nebraska

I started one of my winter projects today. Since the car was already up in the air i decided to install the 86 944 turbo 4 piston brake calipers on my 924S. I'm writing about phase 1- the rear brakes.
Wheels off, old calipers removed, rotors off all in less than 1/2 hour.
New calipers, spacers, rotors and(16") wheels back on less than a 1/2 hour. (15 minutes each side extra for the parking brake shoes and a little lubing) It doesn't happen often but everything worked the way its supposed to. I was sitting back at the breakfast table with my wife staring at me to do chores. So instead of chores. I bled the brakes, got the car down and drove it around the block. So far so good.

Next step phase 2- the front brakes.
the car is in the air, wheels off, calipers and rotors off- half hour.
New slotted rotors on, new calipers on, new stainless lines hooked up, 16" wheels on and we're done. Took an hour but I was having fun so I didn't realy notice.

This weekend will be the road test. It looks great big black calipers and slotted rotors peeking out of Design 90 rims.
4 calipers, 2 spacers and longer bolts at the rear, 4 rotors, new brake lines and 16 inch wheels. I was so amazed how well it went together.
I'm using an ultra high temp synthetic fluid so if it doesn't eat the seals I should be able to stop better than ever.

Next post Ill brag about the better stopping or I'll whine about the crumpled mess that used to be my pride and joy.

_________________
86 924S + 86 944T = one big smile
There is no quick fix or cheap power, not in the Porsche world so learn to drive your car.

Peter_in_AU · Joined: 29 Jul 2001 Posts: 2743 Location: Sydney, Australia

that is soooo good!

Be nice if a few more people posted their success stories.
_________________
1979 924 (Gone to a better place)
1974 Lotus 7 S4 "Big Valve" Twin-cam (waiting)
1982 924 (As featured on Wikipedia)

Learn to love your multimeter and may the search be with you

924RACR · Posted: Sat Jan 18, 2003 2:08 am Post subject:

Wait! We need details!!!

Did the 951 calipers just bolt up to the stock holes? How about rotors - what did you use? Fitment issues if the 951 parts? How about the brake MC - did you change it?

Looking forward to hearing results...
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

chriso · Joined: 23 Dec 2002 Posts: 36 Location: Lincoln Nebraska

On the 924s(rear brakes) the 1986 951 calipers and rotors were a direct change over. The '86 951 has the same size calipers all 4 corners. The only thing that is different is that the back calipers have a .140"(all of my calipers are in SAE measure- Santa wasn't that generous this year) thick washer between the mount and the caliper to get the correct alignment on the rotor. Just to be safe I switched out the original bolts with new ones that were about .2" longer. I didn't have to elongate any holes or make any modifications. I expected a war but it was a breeze.

The only thing about the fronts that is different is the amount of worry I started the job with. PowerHaus in Phoenix AZ warned me that I might have to have custom spacers made and "stretch the bolt holes" and all sorts of stuff that would go wrong when I'm attached to one end of the wrench. PowerHaus is putting together a direct bolt on kit for MOSS Racing but they hadn't done the front end yet. I just sent them pictures and details of the front swap. The only difference in their conversion is that they are using later 951/968 parts. The later 951/968 parts have different spacing requirements so that is why they gave me all the warnings. When they heard that the 86 951 stuff was a direct swap all I got was a bunch of static about me being afraid to try a really creative swap. And then a bunch of cussing because they were having trouble aligning the calipers on the rotors and they would have been done if they would of checked the specs. on the different model years. Basicly they said I was lucky(I agree) and don't expect it to happen again.

Alot of this went so well because I have a 951 sitting next to the 924s and I can check to make sure its all together correctly.

Final caution- have your 16" wheels and tires ready to go. This goes together sooo easy that after you bleed the system you'll want to try it out.

Personal note- 6.5" of snow so I won't get to road test the swap for a week or so.

But it looks fantastic and except for the people reading this I can make up all kinds of horror stories about how difficult the job was and how brilliant and courageous I was to not only attempt but to succeed in this task.

I got the 4 calipers & 4 rotors for less than $200 US. The deals are out there. I then added lines and pads for another $120.00. The 16" wheels and rims are spare track wheels from the 951 and will do just fine until the right deal comes along.
_________________
86 924S + 86 944T = one big smile
There is no quick fix or cheap power, not in the Porsche world so learn to drive your car.

dgz924s · Joined: 03 Nov 2002 Posts: 592 Location: Kansas

"Final caution- have your 16" wheels and tires ready to go. This goes together sooo easy that after you bleed the system you'll want to try it out." Chriso....... Are we to assume 15's won't fit? Or just you prefer the 16"?

D
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Dal Glassinger

924RACR · Posted: Sat Jan 18, 2003 4:50 am Post subject:

Excellent!

IIRC you do need the 16" rims to fit over the bigger brakes.

Make sure you carefully test out the proportioning (front/rear) on the road - make sure it's still OK.

I also wonder how the early brake MC handles the (possibly) larger volume for the big calipers. How's your pedal travel?
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

chriso · Joined: 23 Dec 2002 Posts: 36 Location: Lincoln Nebraska

924RACR is correct!!!
15" wheels are too small. Clearance is gained by using 16" or larger.
Minor clearance issues on my car due to aftermarket springs and shocks(adjustable-problem solved) and tire width(spare track wheels for 951) also solved by using winter rims and tires from 951.
Now I'm just waiting for the snow to melt so I can test the handiwork.
_________________
86 924S + 86 944T = one big smile
There is no quick fix or cheap power, not in the Porsche world so learn to drive your car.

gohim · Joined: 02 Nov 2002 Posts: 4459 Location: Rialto, CA

From looking at the parts books, I can see that the 86 944T uses the same trailing arms, master cylinder, and brake booster as the 924S.

The steering knuckles are different.

What I would like to know is how the car's brake balance works out. The 944T has a proportioning valve, which you can use to change the brake bias, by swapping out a part. If the front and rear calipers have the same size pad, then the rear brakes are going to be out of balance ()too heavy).

The 924S does not have the proportioning valve, so I am guessing that the rear brakes are going to be too heavy, and a swap to 951 brake lines and the proportioning valve will be indicated for future installation.

Mailman · Joined: 14 Mar 2003 Posts: 22

Do the 924S steering knuckles have a 94mm caliper mount like the 944T or 76mm like the 924? Also, does the 924S have the hole for the speedo cable, as the older 924?

Mailman · Joined: 14 Mar 2003 Posts: 22

Also does the 944T rotor bolt to the 924S hub?

Mailman · Joined: 14 Mar 2003 Posts: 22

I looked up the part number and the 924S spindles are the same as the 83-85 944 which have a 76mm caliper bolt spacing thus the 944T calipers with a 94mm caliper bolt spacing could not "just bolt on easy" as stated in the the original post. Unless I have some facts wrong.

Mailman · Joined: 14 Mar 2003 Posts: 22

Lizard · Posted: Sat Mar 15, 2003 1:56 am Post subject:

pictures say it all eh
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3 928s,

gohim · Joined: 02 Nov 2002 Posts: 4459 Location: Rialto, CA

The 86 944T/951 used different steering knuckles from earlier NA cars, later NA cars, and even later 944T/951 models.

The 86 944T also used different front calipers than all other 944Ts.

Without confirmation from the person who did the caliper conversion about the year of the parts that he used, and the year of the parts that were shown in the photos, no conclusion about the compatibility of the steering knuckles can be drawn. After all, the original party that started this topic wrote that the parts were from a 86 944T, and the party posting the photos did not identify where the parts in the photo came from.

turbobob9242 · Joined: 08 Feb 2003 Posts: 138 Location: Hinckely Ohio

This seems too easy!

I know for a fact that the spindles are different on early 944 cars.

The mounts to the strut towers are about 1/4 inch wider but there does not seem to be enough material to make the holes wider.

I must be missing something here....
_________________
Bob Ward
80 9214 turbo, w 5.3 LS V8