944 Turbo brake upgrade questions
 

I have an opportunity to buy a complete set of 993 brakes (big blacks) and have a few questions for the experts here. Sorry if there is no "order" to the questions:

1- What would yu say is a set of used big blacks in good condition with "'almost new" zimmerman rotors worth right now?

2- Will these fit a 1987 951 (without the MO30 option)? I read that on the 87 T, I will need a bracket for the calipers to fit. Is that correct?

3- I already have ss brake lines on the stock turbo brakes. Will these fit the big blacks or do I need to run different brake lines?

4- Can someone recommend a good source or a thread explaining the differences in brakes from 87 Turbo to 88, 89 and the S2.

Thank you all in advance.

1 - Don't know a good price.

2 - Yes they will fit. You do need an adapter as the calipers mount radially and yours mount axially.

3 - You don't need to change your brake lines. the SS lines only go between the hard lines, the hard lines attach to the calipers.

4 - Do a search here. I used google and a few good ones popped up.

Here is a photo:

Turbo S M030 : 928 GTS (Big black) : Stock 944 Turbo (Non-M030)
Attachment 1210485

If these rotors are off a 993 twin turbo (brake rotor disc is bolted to a centre hub) then you can use them with a custom aluminum billett "top hat" or hub available from either Lindsey Racing or Kokeln Racing. If the centre hub is cast with the rotor, like the rotors on your 944, then they will not fit, as the offset of the 993 rotors do not match those of a 944 (reason for the aluminum "top hat" or hib with the TT rotors). 928 GTS rotors match in the 944 offset and will fit the 944 with "Big Blacks". You will also need 17" wheels to clear the brakes.

Thank you for the info gents.

The seller had these on a 944S2. I have to find out about the rotors.

Just to clarify, do the 993 and 993TT use different calipers or the same big blacks with different rotor (sizes)?

Different calipers & rotors. 993 have 951S/928S4 size medium blacks and 993 TT have Big Reds.


i like these more :)

Attachment 1210481
Attachment 1210482

A friend of mine fabricated these hats for 993 T rotors old ET 951 installation

Attachment 1210483

If old style hub is not wanted with newer & bigger calipers/rotors, you can go to these hubs with newer style rotor and still have your current ET wheels.

Attachment 1210484
http://i5.photobucket.com/albums/y17...P/9668348a.jpg

It’s a pity that John D does not run Rennlist anymore – I would ask him to come up with a ‘broken record’ smiley for some of my most often repeated bits of info!
So – here goes!
First I will answer the unasked question – why are you upgrading from a the small blacks (86-89 944 Turbo (non S), S2 and 968 (non M030) brakes) to the larger big black/reds (big black and big reds are the same except for the location of the cross over tube and bleeders – they are on opposite ends and can be switched easily). There are only two ‘real’ answers and I only like one of them…
Brakes larger than the mid blacks will only show benefit out on the track and then only once you are up to speed as a good driver. If you are not using the small blacks to 100% of their heat rejection capacity (pretty damn near impossible on the street) then you are just adding weight to the suspension and reducing the cold braking ability. The other answer that is ‘real’ is that you just want them for the bigger look….I can’t argue with people on aesthetics – but reducing performance (weight and cold braking) for looks doesn’t work well with my thought process.

Some ‘unbiased’ technical info –
You need caliper adapters to run mid-blacks, big blacks/reds (or a set of turbo s spindles/hubs) – its the same adapter for both calipers. The 993TT and 964t rotor will work with the big blacks/reds on the 87/88 944 turbo and all non M030 S2 and 968s. You will need 17” rims to clear the rotors.
Bigger brakes will not really slow your car any better unless you have exceeded the capacity of the smaller brakes, you will not get ‘better’ braking, in fact the stock set up is easier to modulate and avoid lock up right up to the point that they overheat.

But they still look ‘cooler’ to most folks…. :)

As for price...I would not get excited unless you are looking at under $600....

This was amusing to me.
I agree 100%, especially "look cooler".
We all know noone here can honestly diaparage anyone for wanting to look cool - we must all be guilty of this.

Chris,
How do you feel about the cross drilled rotors for our cars? I know that they do not work as well as the solid ones, but if someone was going for a cooler street look. Hey! cant beat the cool factor look of a cross drilled 993tt rotor.

Cross drilled rotors are for ricers….
Cast hole rotors are for Porsches!

What’s the difference? The aftermarket stuff is just a ‘regular’ rotor with holes drilled into them. Drilling holes creates stress risers and those rotors will develop cracks if used hard (like track use – not street use). If you make the original casting with holes as part of the casting process then the holes are much more crack resistant – they will still crack from track use but at a much slower pace. The 964T and 993TT rotors are cast hole rotors.

Holy rotors are mostly just for show. In fact most of the crap you here is just that – crap. In fact the first race car with holy rotors was the 917 – and they did it to make them lighter, not all this ‘off gassing’ crap that you here from some of the pitch men.

If you want cool looking go with the two piece rotor, that is more of a performance look to me!

BTW – if you really like the holy rotor thing there are cast hole rotors available for the rear of the late offset 944 – they were on the 968 club sport option list. Not cheap!! - $280 each list price.

:p A bone stock Pinto's HP and brakes surpass my abilities... but that does not stop me from modding my car :)

Now Ollie's brakes are too cool for school, awesome :thumbup:

I agree with the under $600, including some decent pads

Now this is exactly the kind of information I was looking for. Indeed, that's why I didn't just buy them and thought about it later.

I do use the car on the track but have frankly not pushed the car hard enough to justify the bigger brakes. Now, that's obviously something I hope to change as I get more seat time and since this set came up, I thought I might buy them and hang on to them for later.

I will keep this post as not make Chris explain this AGAIN !!!

A cheap upgrade is to put the 968 brake ducts on to help cooling - about $60 in parts. Search for "968 brake duct".

Edit: here y'are https://rennlist.com/forums/944-turb...deflector.html

Mike

+1, but you have to have the A arms with the attachment points or fab up your own.

Further to Chris' point. There are quite a few people that have gone up to Big Reds and felt their braking go backwards. There is a common theme of a longer pedal travel. Obviously not across the board but enough to be aware of. I had the same issues for some time. It seemed to abate with the OEM holy rotors from the 965turbo, but they cracked very quickly on track. Went to a floating, slotted rotor that works great + also reduced the unsprung weight. Bottom line, really for a street car you don't need bigger than the 'Medium' blacks...but of course Olli's versions always look the best. ;)

Not to go off topic but does anyone know if its possible to add ABS to non ABS car? My 87 T i believe it was an option?

I know there is a computer, pump, and sensors on all the wheel but is it as simple as bolting it in?

Funny you should mention this. I'm about to do the same thing if I don't use an alternative system. You need the correct hubs too. Possibly there is a difference to the brake lines that may need to be changed from a non abs to the abs version. You'll need a harness too. We're just sending an email to Porsche to see if they still have the harnesses and even brake lines available. I'll report back on this.