[W126 Coupe] Brake Pads

[Jonathan Hodgman]

Oh, my fronts took utter abuse, but the car isn't pushing, @ least not like
it does when I over cook it on the street.  My left front tyre was all but
done after the w/e, while the other three were looking OK (only 3 left hand
turns).  Perhaps you might try changing out your suspension for more
conventional bits?  Also, are you allowed to run larger wheels?  16's give
you a little too much sidewall IMHO.  How do you have your front suspension
set?  I'm running 2 degrees negative camber up front (I usually run 1on the
street)...

I would also recommend getting rid of those Bridgestone RE71's and getting a
more track oriented tyre.  From the pictures I am seeing you have Way too
many tread blocks and the tread wear is Very high for running on the track.
The only 71's I could find were of the runflat variety, if yours are the
same I'd say that's one more reason to move onto a different tyre.  Runflats
are not an ideal track tyre.

My car should be making about 250KW @ the wheels.  I am also running a
2.82gleason style locking diff..  I never shifted below 3rd on the
whole track,
and only shift twice..once up to 4th on the back straight and then back down
again while braking for the next turn.

The 220KW version is a mix of cams, pistons, displacement, computers, EHA
differences etc..

My car used to have the full AMG active suspension, but they/it was known
for having issues/prone to leaks and was thus switched back to conventional
suspension.



I noted your other post on exhaust, should you be interested I am
duplicating AMG's headers for our cars as well as mandrel bent stainless
down pipes.

Or, in the next year or so I should have my TT setup sorted and available to
interested parties;-)
Jonathan


On 4/2/07, Divov <divov at tiscali.co.za> wrote:

>

>  I am amazed that you say your car doesn't understeer because these are

> understeering cars by design which is what makes them so safe and docile as

> street cars.

> Next time you race, as you pit, jump out and feel your tyre temperatures.

> My front tyres were very considerably hotter than the rears which clearly

> shows they are working a hell of a lot harder. I felt in some corners I was

> 4 wheel drifting - tyres screaming like hell - but just kept the power full

> on as there was still enough road left and the car was stable. In the

> tight stuff I was definitely having understeer. Only a total of 30 - 40

> miles race distance and previously 50% worn front tyres were totally

> trashed. Its a right hand corner circuit so left outer smooth and right side

> inner smooth.

> I only have 170KW compared to a Euro 560 which has 220KW so you can use

> your extra power to break rear traction and hang the back out.

> A difference of 50KW is massive. Where does a 560 get all this extra

> grunt? Surely not just from an extra 600cc?

> I had my car on a Dyno and got 150hp on the wheels which the guys said was

> exactly par for a 500 on *their* dyno.

> Note that we are at 6000ft altitude and as a rule of thumb we are 17% down

> on coastal power output & no 2 dyno's read the same so it is comparing

> apples to bananas.

>

> I have considered using double stock anti-roll bars because the design of

> the merc anti roll bar is not as simple to fabricate as on many other cars

> and also I happen to have a spare AR bar. Just have to figure out a mounting

> arrangement which I don't think will be too difficult.

> Re: tyres used. See my previous post - Bridgestone RE 71.

> Pressures were cold. (tyres filled with Nitrogen - not air.)

> Re: Shocks - I am using the Bilstein AMG adjustable shocks. Front were set

> full soft and rear set full hard.

> Springs: Front are cut down stock springs and rears are H & R's replacing

> the self levelling suspension.

> Lowered front by a whopping 85mm (previously my car always

> stood particularly high in the front) & rear by about 70mm

>

> ----- Original Message -----

> *From:* Jonathan Hodgman <jhodgman at gmail.com>

> *To:* Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>

> *Sent:* Monday, April 02, 2007 6:55 PM

> *Subject:* Re: [W126 Coupe] Brake Pads

>

> Hello Alex,

> Yes, very different conditions as well! Road Atlanta is fairly long,

> 4.088k. My brakes were OK aside from the one hard stop from from 230 kph

> down to 80 or less kph.  Right before this run is the 2nd hardest braking

> point on the track.  Brake fluid was about 20 hours old when I went out;-)

>

> To be honest, the car doesn't really understeer..  I have switched all my

> springs for fresh H&R's, running 2 nib in the front, 3 nib spacers in the

> rear.  I'm using Bilstein HD shocks all around.  The next time I go out I'm

> going to add spring rubbers to the shims as I'm getting a bit too much

> compression on the drivers side.  What tyres are you running?  I was using

> Pirelli P-Zero Corsa's 255/40/17's.

>

> Are those tyre pressures hot or cold? I was running 2.75 bar in the front,

> 2.85 bar in the rear.  I found in raising the rear above that caused it to

> get a little loose..

>

> I've have heard differing opinion on running a thicker rear anti roll

> bar..  Some say it will upset the handling, others say it handles much

> better.

>

> Jonathan

> I know one fellow down in AU actually managed to double up on the rear

> bars, and he was thrilled w/ how the car handled.

> On 4/2/07, Divov <divov at tiscali.co.za> wrote:

> >

> >  *Hi Jonathan,*

> > *Bridgestone RE 71  205 55 VR 16 front*

> > *                                     225 50 VR 16 rear*

> > *tyre pressures 2.8 bar front*

> > *                          3.2 bar rear*

> > **

> > *Track is very short & very tight. Lap times 58 sec!*

> > *Max speed down main straight is only 150kph then braking into a hairpin

> > bend.*

> > *Back straight maybe 130/135 kph braking into hairpin.*

> > *Two other braking points.*

> > *Brakes never have a long time to recover.....*

> > *Very different conditions to your track.*

> > *Lichtenburg circuit has a reputation for being hell on the brakes.*

> > **

> > *How fresh is your brake fluid?*

> > *I had boiling fluid until I flushed it out & put in fresh fluid.*

> > **

> > *What have you done to counter the under steer?*

> > *Are you still on stock rear anti roll bar?*

> > **

> > *I think I need to make up a new one 16mm diam in place of the stock

> > 14mm item.*

> > *Is that going to be enough? - time will tell.*

> > **

> > *I also melted the sensors long ago. Don't bother will them on the

> > track.*

> > **

> > *Alec*

> >

>

> --

> Blue Ridge Mercedes/AMG East

> Offering Enthusiast Service, Restoration and Modification.

> Providing quality parts to discriminating customers in all parts of the

> world.

> Located in the Greater Atlanta area.

> http://www.blueridgemb.com

> http://www.AMGEast.com

>

> 1996 S600 Euro "Scharnhorst"

> 1991 560 SEC Full Euro ECE

> 1991 560 SEC 226Hp/271ft/lbs:)

> 1989 560 SEC AMG (N.Amer 250/295)

> 1987 560 SEC US Spec

> 1986 560 SEL AMG 6.0L 32V

> 1986 560 SL  White on Burgundy

> 1985 500 SEL Euro (Parts Car)

> 1985 300 CD For Sale

> 1980 280 SE Euro

> 1978 300D TMU

> 1987 560 SEL 162K Midnight Blue on Gray RIP:(

> 1987 560 SEC Sold

> 1992 E300D 140K Champagne on Parchment tex (Sold)

> 1990 560 SEC 154K Anthracite on Gray (Sold)

> 1988 300 TE 160K Burgundy on Palomino (Sold)

> 1980 280 SE US 185K (Sold)

> 2006 Z4 3.0Si M spec 6sp

>

> ------------------------------

>

> The MB Coupes Website!

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> Postings remain property of MB Coupes, L.L.C.

>

>

> The MB Coupes Website!

> W126 SEC Mailing List

> Postings remain property of MB Coupes, L.L.C.

>




-- 
Blue Ridge Mercedes/AMG East
Offering Enthusiast Service, Restoration and Modification.
Providing quality parts to discriminating customers in all parts of the
world.
Located in the Greater Atlanta area.
http://www.blueridgemb.com
http://www.AMGEast.com

1996 S600 Euro "Scharnhorst"
1991 560 SEC Full Euro ECE
1991 560 SEC 226Hp/271ft/lbs:)
1989 560 SEC AMG (N.Amer 250/295)
1987 560 SEC US Spec
1986 560 SEL AMG 6.0L 32V
1986 560 SL  White on Burgundy
1985 500 SEL Euro (Parts Car)
1985 300 CD For Sale
1980 280 SE Euro
1978 300D TMU
1987 560 SEL 162K Midnight Blue on Gray RIP:(
1987 560 SEC Sold
1992 E300D 140K Champagne on Parchment tex (Sold)
1990 560 SEC 154K Anthracite on Gray (Sold)
1988 300 TE 160K Burgundy on Palomino (Sold)
1980 280 SE US 185K (Sold)
2006 Z4 3.0Si M spec 6sp
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