10 replies to this topic

[johnvx220]

When braking hard it is always the front that locks up first then the abs cuts in. This was the case in the na and now the vxt. I dont drive the to limit so does it make sense to have a softer compound at the rear so more effort in the braking would go to the back tyres. The abs does not like fast braking while turning at great speed and on both cars just gives in and the wheels lock in a suffing slid. Any thoughts?

[BradW]

Huh? (P.S. This evenings posts are a clear attempt at boosting my number of posts. I have taken the 'Reply to everything despite lack of knowledge' route! )

[clipping_point]

If the rears would lock up first you would spin off, so isn´t it natural that the fronts lock up first?

[cyberman]

If the rears would lock up first you would spin off, so isn´t it natural that the fronts lock up first?

Forgive a modest pedantry but I think you mean "preferred" and not "natural".

Johnvx220 suggests putting sticky tyres on the rear to improve braking. There are many places you can interfere with the braking balance front to rear and the point at which one end or the other will lock up. However I respectfully suggest that to *improve braking only* this is the wrong end at which to put sticky tyres.

As most braking work is done on the front (because of weight transfer) and because the front end tends to lock first (by design for safety reasons) then putting sticky tyres on the front probably would improve the overall efficiency.

However, only because you have ABS is this relatively safe for if you alter the braking mode adhesion balance enough to make the rear lock first then the ABS should deal with it. You won't catch me relying on it as I prefer systems that are intrinsically safe...

However, it will also alter the limiting slip balance front to rear in corners and you are likely to find yourself with a car which likes to waltz if you interfere with it in this assymetric fashion. Really only to be tried on the track I think where the unexpected can be significantly less costly.

Kind regards - Ian

[johnvx220]

Thank Ian you for your advice and as I said it was only a thought. John

[clipping_point]

.. my idea of how to improve MY braking is to use wider tires 195/205 in front. May worsen the handling, tho.

[goofballs]

Putting green stuff pads on mine reduced the point at which the locking began, I am now very happy when braking, dry and wet. I still haven't changed the rears either!! Putting larger section tyres on the front will probably have a similar outcome, however, a set of green stuff pads on the front are even cheaper than the standard vauxhall pads, so I would presonally go for these first. cheers

[Ricky2772]

susp. geometry has a lot to do how the brakes react.... when you have a lot of camber and toe-in at the rear, you'll get instability/lock-ups at the rear first. a bit more camber at the front will help as well.... deffo installing 195, softer compunds lie yoko 048 at the front makes a big difference. could try toyo's front+rear, quite good it seems.

[clipping_point]

Thanx for the advice. The EBC greenstuff pads are a real bargain so I´ll try them cheers

[clipping_point]

..and the Toyos (if they fit my 17"-s) cheers

[goofballs]

let the greenstuffs bed in properly before you draw any conclusions, at the beginning they can be quite slippery. cheers