Tech reading for all big brake freaks :)

[kwlw]

Hallo,

Just spotted on some bimmer US forums some link, as "highly recommended tech reading" :

http://www.teamscr.com/grmbrakes.htm

At the moment just took glance, seems to be very interesting article, with many FAQ's answered, so I couldn't hide this from //S2 community :mischeif:

Sau
P.S. bummer 4pot brakes design for my big fat cow - in progress!!

[HPmuirt]

Excellent article

As one who is upgrading to the Porsche brakes at the moment...the article leads to several questions....

1. What is the difference (if any) between the S2 and RS2 Master cylinders?

2. Has anyone added cooling ducts to the front discs and if so, did it improve the braking when hot?

Cheers n

Si

[S2central.net]

1. NONE - they are the same master cylinder. I checked this years ago... Lucky huh !

2. I haven't but others have - the RS2 actually has some ducting in this regard

[dan_b]

It is a good article, and a good site generally. However you shouldn't come away with thinking that the standard S2 brake setup is fine afterall!

I know that when Lee produced his 365mm AP 6-pot brakes he also then went to 245 tyres up front to give the brakes more to work on. It's also the reason why I've always bought the softest, stickiest road tyres available.

[HPmuirt]

1. NONE - they are the same master cylinder. I checked this years ago... Lucky huh !

2. I haven't but others have - the RS2 actually has some ducting in this regard

Thanks Paul

Cheers n

Si

Note to self....add RS2 brake ducts to wish list
Note to self....don't tell wife how big wish list is now

[Jamo]

Be careful of american articles, they're all phrased in ways that their right, everything else is wrong and panic stations if you think otherwise.

[The Spanish]

About brake cooling. Cup 1 tyres (RS2 standards) are supposed to force air inside the rim to cool the brakes on the move

[The Spanish]

Ome more thing I remember to read and article on tyres on Sport Auto German.

160Km/h (100mph) to 0 on a Porsche 996 standard Pirelly Pzero Rosso was 96 meters, with Yokohama A038 semi-slick rubber was around 75 meters , yes it was that much.

[Jas11n]

Thanks Paul

Cheers n

Si

Note to self....add RS2 brake ducts to wish list
Note to self....don't tell wife how big wish list is now

Be interesting to see if you have the RS2 disc splash plates on yours Si, Mines got em from the factory, and so does my bro's and one other 95 S2 that I know of, I can't however fit those RS2 airducts as I have the pressed wishbones as opposed to the other S2/RS2 cast type and they won't fit

Jas

[dan_b]

One more thing I remember to read and article on tyres on Sport Auto German.

160Km/h (100mph) to 0 on a Porsche 996 standard Pirelly Pzero Rosso was 96 meters, with Yokohama A038 semi-slick rubber was around 75 meters , yes it was that much.

That's why I'm seriously considering getting the Toyo R-888s on my S2, at least for spring - autumn use, or if not those then at least going to fatter rubber generally. Anyone tried a 235 section tyre on a 17"?

What's the UK highway code official stopping distance for a car at 70mph in the dry? 100 metres isn't it? Hmm.

[Greg_S]

you can put 235/40' on there instead of 225/45's there is a slight difference in rolling radius but not huge

[dan_b]

Would it be worth it do you think - 235/40 at the front, and keeping my basically almost new 225/45s on the back? 20mm of extra friction at the front, bit more understeer, bit more tramlining I expect, but hopefully a bit of extra braking too? Hmm.

[Sir Buff]

@dan_b
This gives less understeer.
Look at the MTM RSR:
265/35 ZR 17x10" front
235/40 ZR 17x8" rear

[dan_b]

I think my wheels (Mile Miglia Cup 1 replicas) are 7.5" width, so I probably couldn't go over a 245 at the front or I'd run in to major fitting issues.

I thought that if you added traction to the front you effectively increase understeer?

[Jamo]

I think my wheels (Mile Miglia Cup 1 replicas) are 7.5" width, so I probably couldn't go over a 245 at the front or I'd run in to major fitting issues.

I thought that if you added traction to the front you effectively increase understeer?

Think about 4 wheel drive mate not 2wd drive, more traction on the front wheels on a 4wd car gives better corning ability.