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I'm just looking forward to the dry weather!

Nice update mate
Hopefully you can give them a proper test when the weather improves

Just been out an done some try testing. 14o-c outside temp this time, so 4 deg warmer. After I got in last time, my dad told me 30-0 used to be a common distance, so I checked that one too this time - 3 meters!







That's braking at the sign, and stopping there. That's a repeatable result too!

It's worth noting all distances are from when the sign leaves my view, to where the back wheel is, so is you take into account the length of the car, it's a bit longer but this is consistent to the 1st test.

For the 60-0 tests;
1) 25m (going ~5mph too fast)
2) 23m
3) 23m (I couldn't see where I marked this one on the floor, but I think it was bunched in with 2 & 4)
4) 23m
5) 26m
6) 20.5m
7) 23m
17m (tiny bit too slow here and 9 I think so discounted in average)
9) 18m
10) 24m
Average: 23m
Reduction vs. standard brakes: 3m

Notice that there is NO fade at all in these distances though, so for heavy track work (which the car will be getting soon if things go well) they look like they should be better. They also give a MUCH better feel/performance if you brake progressively, rather than slamming the brakes on but I figured that would be hard to measure. If you slam the brakes on you end up in a world of ABS kickback, so the power is there, but the grip doesn't seem to be. If you brake progressively down from a speed, you don't suffer the ABS kicking-in in the same way and you feel as if you're going to stop a lot sooner than standard.

Worth it in stopping distances in a full on situation? Not really (although that 3m could save a crash I guess.)
Worth it in progressive braking? Yes!
Worth it in feel? Yes.
Would I spend the money again? 90% yes.

I'd like to get a standard/280mm car and do some side-by-side 60-0 runs now to see the difference but no-one lives locally.

Any questions, feel free to ask!

Joe

Have really enjoyed this thread.
nice bit of work, and its great youve gone through the effort of doing all the test results.
interesting conclusion in the end. glad youre happy you did it

Nice results mate and thanks very much for posting such a detailed and informative thread excellent stuff!

Very informative thread and has been a pleasure to follow. Hope you're happy with the results and hopefully they'll help someone else out in the future.

Nice work mate. Thanks for sharing this with us. It's been very interesting and when i get bored of mine I will probably do the same

Glad people found it interesting.

Just a few miles on type thing really - feel is much better now it's bedded in properly. My dad drove it and said it's much better (I guess I got used to it as it bedded in slowly).

It has raised an issue though - the back end. Braking hard now gets the back end really lose (not surprising!). Does anyone know of any decent rear upgrades to the back brakes? I did look at the 256mm set up off of an Ocvtavia vRS etc, but they need 16inch rims which I'm not going to upgrade too. I guess an alternative is a bias valve, or to lower it (on the cards!), but ideally I'd like to try improving the brakes themselves first. I'm guessing there's not much out there as my Golf has the same rear set up as the Polo, and the next stage up from that was the 256mm rears. . .

Just to finish this off completely, the brakes are now off the car ready for selling and the stock 256's are back on. It's a massive reduction in stopping power! Standing on the brakes and the ABS only just kicks in compared to the 4 pots where moderate braking would trigger it easily - the car still stops quite well though. The feel is also terrible again in comparison, much more wooden and generally less pleasant to drive with, pretty much as it was with the G60 setup. With the 4 pots it wasn't too far off the feel in the 330, and they're very nice brakes!

What I shall do though is try and measure the braking distances again with the stock brakes, see how much ultimate difference there is - just need it to dry out again.

Right, just to get 'closure' on this I've been and tested the standard 256 brakes with surprising results!

All tests were done on the same road, except the 256s were tested with a ~6-9*c hotter air temp. All pads and disks were Pagids, and the brake fluid was the same make all the time, and it was on the same set of tyres (Uniroyal RainSports - awesome tyre!).

Anyway, from 60, same as before, dropping the clutch as I pressed the brakes so there was no engine braking to change results.

1) 25
2) 20 (too soon)
3) 27
4) 24
5) It seems I missed 5!
6) 23
7) 21.5
8.) 21.5
9) 25
10) 20.5
Average (not including 2 or 5) of 23.4. Doesn't mean much on its own, but when compared to the other brakes it gets a bit more interesting:

Averages for all 3 setups once outliers (too slow, too soon etc) have been removed:



Stopping trends for each setup:



As you can see, the 256 and 4pots are pretty much identical, with the G60 setup trailing behind! Why? I'm not sure, but have a few thoughts. When testing the 256's it was anywhere between 19*c and 23*c, hotter than it was with the other two at 14*c. Would this make enough difference to a standard road car though?

The 256's are smaller/lighter than the G60s, and the G60 offers nothing other than increased leverage/looks. Is the extra weight of the bigger disk enough to counter out the increased leverage? The 4pots are bigger (and heavier disks), but the calliper AND carrier is lighter than JUST the VW calliper. I don't know if that's the reason, it's just speculation by me.

You can also see in the 2nd graph that the 4pots are usually the best stoppers, and when they do beat the 256's it's by a decent margin, whereas when the 256's stop faster it's generally a much closer result.

You maybe thinking then, what's the point of the 4pot setup? Two things - first, stopping from 30mph. With the 256 brakes stopping from 30mph takes 4.5-5 meters (to the back of the car). With the 4pots, it's down to 3 meters. In town, if a kid runs out or whatever, that could easily make a big difference to how events unfold. Secondly, and why I changed in the first place - feel! The 4pots are much, much more powerful mid travel and were often triggering the ABS in normal driving under lighter loads where the 256s still feel numb and inert. With the 4pots, there was genuine feel/modulation there whereas the standard 256s you just press harder and harder, there's nothing coming back to tell you what's happening as such. For that alone, I'd upgrade the brakes as it makes the car soooo much nicer to drive. With the G60's, feel remained the same (same calliper).

So there we have it - by my testing the G60 is a pointless upgrade if your intention is to stop faster. That said, I've got a set for sale if anyone's interested!

Of course, this isn't scientific at all, and only reflect my findings, but I thought it maybe of interest to people all the same.

Really intresting to read good work

Top work mate. Very interesting conclusion to the testing. So G60's just look better hah

Excellent Work Joe

Good write up mate, g60's are all show no go. No increased surface area for pad so no better breaking performance really as your test shows. Looks only. But either way the 4pots are better. Maybe better pads and discs would make a better stopping result?

Either way good work.