I can see how this doesn't appear to address a bias improvement but I'm going to start off with just the DS2500's all round.
If you just use DS2500s all round, then you might actually make the bias worse - simply due to the compound of the DS2500.
....Had a chat last night with my friend who no longer works at VWR but who did my suspension and is very experienced at setting up cars.
He suggested the same as you suggested might happen with DS2500's on the rear
Great minds think alike!
but said I'd be okay if I kept my ESP on.
Hmmmmmm . . . . the actual
ESP wont really be a great help in controlling the actual bias - the bias is controlled by the 'Electronic Brakeforce Distribution' (EBD), which is still a component of the ESP/ABS system. But the EBD (and ABS) is map controlled, and just like an engine will gain no advantage from using BP 102 on a standard engine map. Which is why I keep going on about improving the rear brakes with bigger discs & caliper pistons when fronts are improved. But the ESP should certainly help to keep you away from the kitty litter or hedges.
But the most
important issue regarding the ESP - is simply that the Golf Mk5 doesn't actually
need it. The Golf 5 chassis is beautifully balanced, and categorically does NOT need any
assistance in the handling balance - with the standard brakes. If you can give 100% concentration to your driving, without any other distractions (screaming kids, nagging SWMBOs, or totty spotting :embarassed:) - then in all honesty, the ESP should be turned off.
He also told me that if I kept the ESP button depressed for a minimum of 10 second it would also switch off all the ABS etc.
Nope. Only the 'stability' and 'traction' releated components of the ESP can be turned off. That means the ESP, and the undocumented CBC (Cornering Brake Control), along with ASR and EDL. But any of the actual 'braking' functions definately can NOT be turned off - so you can't turn off the ABS, EBD or BA. This is the case on all cars, even those with three-stage ESPs such as Audi RS cars, and multi-stage ESPs such as on some high-end sports cars like Lambos and Fezzers.
So someone has been telling porkies!
We both agreed that I'd feel more confident with ESP left On.
ETTO and all that, but the Mk5 GTI, on decent tyres does not need the ESP.
VWR tell me that stiffening the front end will help weight transfer and hence reduce rear end twitchiness under braking
But that will only really work when you are in a dead straight line, on a flat and level road. The moment you apply some steering input, or get lateral forces due to leaning road surfaces, or even noticeable side winds - then there is a high probablility that the back end will brake away much sooner, and with much less warning - those traits are fine on the race track, but highly undesireable on the public road.
....Again, my friend would agree with you (and his answers were with absolutely no knowledge of your comments).
Great minds, part deux!
His suggested solution was to let 2 or 3 psi out of my tyres resulting in emulating softer rubber and giving more grip.
Hmmmmmmm . . . . that may be acceptable on a closed race track, but on a public highway, even on a one way toll road
- really shouldn' be recommeded. Lowering the tyre pressure, then hammering round at high speeds, and using the brakes heavily will start to create huge build-up of heat in the tyres - and this is a sure-fire recipe for premature blow-outs. Thruxton race circuit is a very valid demonstrator of this.
This kind of advice really is only appropriate for proper racing tyres, where you need the 'flex' in the solid tread area to heat up the rubber to get grip. But on decent road tyres, the steel belting in the tread plies will prevent the tread area flexing, and will simply make the sidewall flex more, especially the area of the sidewall where it meets the tread area. And lowering front tyre pressures will also make the front end LESS stable, and will 'squirm' around under braking.
Leave that advice for real racing cars, using real racing tyres.
Also, he felt that as my suspension was absolutely in the sweet-spot (apparently VWR have now put the same on their demo car because mine felt better), it was best left alone and, as you say, it needs to serve BOTH road and occasional track. My suspension could be further tweaked for track but it's most definitely good enough for some 62yo GIT!
I totally agree. I think your suspension is set up really sweet, from the little demo you gave me at JKM earlier this year, and is obviously a daily driver. But if you have adjustable damping (I don't know the full detail of the functions of your set-up), then increasing compression damping, especially the high speed compression damping (if they have a separate high and low speed adjustment), would really benefit on track days.
I now feel able to totally justify my purchase of this gizmo : - Tyre Pressure & Temperature Monitor - Group Buy....
Hmmmmm . . . . whilst that is an excellent piece of kit, I reckon it will only serv as a worrying alarm when used on a track - because if you are giving it 10 10ths on a race track, you will be quite alarmed at how the tyre pressures rise.
And the best bit of kit is the simple PCL pencil type tyre pressure guage, along with the good ole Mk1 eyeball.
but, as Hurdy says, this runs the risk of greatly reducing that margin of feedback and the car potentially letting go! I think I'd rather experience the twitchiness as a warning sign than extend my car's limits but with the risk of no feedback before losing it!
Very wise! 
....And with age, comes wisdom (so I'm told!).
Did yours get lost in the post?
