mmccray

As always, I can count on list to come up with some useful advice. Based on the info, I think I might be able to do this in stages. Bill G - thanks for the PN's. I can use those to help initiate a search for decently priced brake parts.

Marshall McCray
1987 944S
1990 C2

viperbob

I am doing Tom's MC 993 upgrade as his current MC is DEAD. So does anyone know when Porsche pushed the prices through the roof on the 964 MC? List price is almost $1400!!! I thought this was a mistake, so I checked with several of my suppliers including Porsche and it was all the same. So this is now not just an upgrade to use the 993 MC (with price under $200), but a way to save big $$$.

I'll take some pics of the process and post back with the required parts when the job is completed... Poor Tommy Turtle.

HODY905

Manny: in your post you said "you got yours from Crescent City Porsche". Did you mean this regarding the "big reds" or regarding the larger brake fluid reservoir?

Bill Gregory

Manny got his Big Reds from Crescent City. There are other discounting Porsche dealers, too, where the parts can be purchased.

FWIW, I don't know anyone who has put a larger brake fluid reservoir on when installing Big Reds. However, the people I know with the conversion also use their 964's at the track, and tend to bleed their brakes often, and inspect fluid levels often. Perhaps the larger brake fluid reservoir, as described by Adrian, would be appropriate for the owner that has someone else change the brake fluid every few years.

Christer

I have never heard about this 'larger reservoir' -and to me it doesn't make sense. You have to have a larger device to pump the fluid, not more fluid unless you just don't like to check your brake fluid very often...

viperbob

So here is an after photo of Tom's Turtle with the 993 master cylinder installed. Everything looks great. I am just waiting for the brake fitting adaptors to be delivered tomorrow and it will be all set too go. This has some tricky parts, especially where the brake servo bolts to the mount. Some maching work must be done on the inside. Also the 993 brake servo is larger in diameter that the 964, so you basically have to take everything out to install it (including the sway bar). I'll post some more photos when I get some time.

tonytaylor

I recall mine just bolted sraight on

However it was a squeeze and, as you say, the sway bar had to come off.

viperbob

Tony - The collar on the 964 brake servo that slides into the mount is beveled, as is the mount. The 993 brake servo has a collar that comes out straight and therefore interferes with the mount when you try and fully insert it.. It took some grinding inside the tube to get it to sit flush. It was not very much to take off. Just about 1mm. The servo would go in, but would not seat properly otherwise.

Gavin

I have an 89/90 C2 which has had RS brakes (discs and calipers) fitted front and rear. The pads are stock porsche items and the flexible hoses are stainless items, fluid Castrol SRF (?). The pedal is very firm with no dead travel, very progressive and extremely powerful and immune to fade (both on road and track). It runs the original master cylinder and servo.
I have heard differing stories about the need to change the master cylinder and the regulator, but I am unsure why as this system works fantastically.

tonytaylor

Out of interest, I presume the 993 mount is different then, would the 993 mount bolt straight on?

viperbob

Yes Tony, you could use the 993 mount. It looks like this piece has a list price of only $65. That may be wrong as it is a large piece of aluminum.

So the project is complete, and Tom's Turtle is off to the track (and I also have to leave in a couple of minutes). The adaptors that I found do work, but require some modification to the existing brake line. They have a bubble flair at the master cylinder which threads perfectly, but they needed an inverted flair on the brake line end. This was about a 20 minute project (if you have knowledge of flaring brake lines and the proper tools) so cut the end off the line, inset an inverted flare fitting, and then flare the end.

The other thing that I noticed is that rod from the new 993 brake servo is slightly shorter. When installed, this caused the brake pedal to come forward towards the floor about an inch. A simple adjustment to the brake rod fixed this and it was good to go.

RSAErick

Ressurecting this thread, in hopes that it prepares everyone better for what I believe to be a common 964 upgrade. Upgrading to a 993 master cylinder and 993 brake booster is not entirely straightforward as I was hoping....




The problem that one will encounter, is that the 993 brake booster (993-355-212-00) will not fit into the the 964 bearing bracket (964-355-495-03). If you look carefully at the differences between the 964 and 993 brake booster, you will see that the location where the booster fits to the bracket is shaped different. As a result, the 993 booster will not fit into the bracket.





According to Viper Bob, the inside surface of the bearing bracket can be ground down sufficiently to accept the 993 booster; or, a 993 bearing bracket (993-355-495-01) can supposedly be used.

Just thought that I'd share the dilema with everyone.

After that, the next challenge for this project:
1. Changing the two brake lines that connect to the 993 master cylinder to 12mm fittings (from the 10mm 964 fittings)
2. Adjusting the brake pedal due to the slightly shorter shaft on the 993 brake booster

Note to self: Nothing is ever straightforward!