How do you VALUE WP Pro brake kits?

[Simon J]

Simon,

Yes, I'd agree with your conclusions about the effect of the larger discs. The mechanical difference between the 280s and the 302s is, I would suggest, almost imperceptible. Would any of us have sufficient sensitivity in our braking to be able to notice a 7% improvement for a given pedal pressure? I doubt it.

The larger disc will, of course, improve cooling and since the 302 has 16% more area than the 280 there should be some greater resistance to fade. The 320s, however, offer some 14% extra braking torque over the 280s which is probably at the level that you would notice the difference and for sure I can say that, compared to the 280s that the car had originally, they do provide significantly better stopping capability. As for resistance to fade, the discs are 30% bigger in area so clearly they will be substantially better at heat dissipation than the 280s. THe figures for the 325 AP discs will be a bit better again.

But there is no doubt in my mind that the stock caliper, or the Volvo Performance one, gives essentially the same mechanical advantage as the four pot AP one. OK, in extremis, the more balanced opposing piston set up of the AP caliper may prove to be better, but I suggest that you would have to drive like a maniac on the public roads to notice the difference. And don't forget, the M series BMWs use basically the same ATE Treves single piston caliper as the Volvo, and while I'm no particular fan of BMWs there is no denying that the M series are pretty serious pieces of kit and if these calipers are good enough for them they should be OK for even a T5.

So why are the AP brakes so good? Well, I think it is a combination of the improved leverage and the increased resistance to fade of the larger disc, plus, and it's a big 'plus', the better friction material in the pads. My 320mm Volvo brakes are very good, but lack the 'bite' that I would have expected them to have. I plan to try the Ferodo Performance pads in the near future and I suspect that they will make a big difference.

It's a very interesting topic and one about which there are a lot of myths propagated!!! But when you analyse it, it is really fairly straightforward. Yes, the fancy grooved and cross drilled discs may look good, but I know from experience that their practical benefits are minimal and pretty much restricted to marginal heat dissipation. Better pads will probably make the single greatest cost effective improvement in braking performance but then the dreaded fade problem will raise its ugly head as the higher coefficient of friction will generate more heat and the standard discs can't cope!

So my conclusion is that if 280s are fitted, do the simple upgrade to standard 302s and fit decent pads. If your driving style still leaves you wondering whether the brakes are going to melt, then bite the bullet for the bigger discs of the AP set up. I can't in all honesty recommend the Volvo Performance Brakes, simply from the point of view of cost - at £1800 they are way too dear when the AP set is two thirds the price. And of course use 5.1 fluid and reinforced hoses - every little helps!!

So there we are - SJ's view on life and Volvo brakes!

Rgds,
Simon J

[sholtby]

When it comes to brakes there are 2 factors then the first is the initial bite and the second is fade ie the ability to maintain that initial bite. Pad choice is important here is it not, as softer pads will give a better bite but if prolonged severe braking is required a soft pad will fade. Hard pads are better suited for track use where higher brake temperatures are maintained.
I think I agree with you Simon, 302 brakes with uprated pads could be the best value for money.
We use a dyno to measure a cars engine output. Is there any way of measuring braking efficiency of these various brake set ups? We could do with some figures here so we can make comparisons.
Don, the problem with your last comment is that there are people who say that there isnt a big improvement after fitting AP brakes as a poll in a previous thread proved.

Simon

I imagine that a specialy setup brake test roller could do this, similar to what MOT bays have.

Adam.

[sholtby]

The trouble would be stopping the wheels from locking/slipping on the rollers.

Simon

[don kalmar union]

Simon(Sholtby),

I really cannot agree with your take on the earlier poll on the effect of AP brakes...if you check back there was only one dissenter and I think 4 well satisfied out of a very few respondants.

On the question of using Ferodo DS 2500... they will certainly add to disc wear and will generate more heat with 280 or 302mm brakes when used hard and we do know that warps these sizes of discs.... anybody's, Volvo, Black Diamond etc., and particularly cheap crap from ECP and elswhere.

It is possible of course to use some wire reinforced ducting to get some air from the lower spotlight vents onto the inside of the discs...it certainly helps if you are into press-on driving.


Don.Norchi.

www.kalmar-union.com

TME engineered software UK distributor.

[sholtby]

The voting figures were about even for those in favour and against AP brakes although I agree that most people who passed comment were in favour.
I think I'll stick with the 'cheap crap' original equipment ATE discs at £30 a go rather than the £300 AP ones.

Simon

[Simon J]

Simon,

I think in fairness to Don he was't suggesting that the OEM ATE discs were cheap crap - but some of the stuff out there surely is!

Simon J

[sholtby]

Thats what ECP sells though!

Simon

There is also Brembo, which we sell with our brake upgrade at around £50 + VAT. There's a big choice out there!!!

Adam.