Rear Brake Pad Upgrades....

[gazbutS3]

I was under the impression the S3 and R32 rear set-ups are the same, might be wrong though

[QD MBE]

....

My understanding is that the DS2500 pad performs better than the oem pad regarding whatever heat generation there is or isn't.

So, stokey, tell us more about your S3 rear brakes - Disc size, pads used, weight, any pics?

Pads used are the std S3 rears, allied with 310 x 22 (i think) mm Discs.  The pics are in the thread linked below.  The weights are heavier, due to larger dia and thickness disc used, also the caliper is larger.  heavier by how much, I dont know.

http://www.mk5golfgti.co.uk/forum/index.php?topic=2113.0

[RedRobin]

....

@ DaveB,

Yes I definitely will be asking AP to clarify about the 85%. But whatever the braking distribution is, my car doesn't front end dive or handle badly as a result.

Whereas I can understand how a certain amount of heat generation is a good thing, I think we all know that too much heat is not a good thing!

It's well known that DS2500 pads, like tyres, need a bit of heat in them to work better but that's easily generated.

Dont know whether its an installation issue but the 2500 compund has been getting a bit of a slating recently over on uk-mkivs, the pad of choice over there at the moment seems to be the pagid blues

....I don't read the uk-mkivs forum but I'm not inclined to view such information as reliable. Someone posts a negative opinion which then starts others wondering and naturally it spreads. Whether the negative comment was right or wrong it happens everywhere on the internet (and elsewhere such as public confidence in the economy etc). What's more important is who expressed the opinion originally and on what basis. Another aspect of car forums is how so many are primarily led by cost considerations in their judgement of products - Perhaps Pagid Blues are cheaper (I don't know).

Do you have a link to this slating of the DS2500's please? [mine have just arrived in the post!]

Thanks

[RedRobin]

....

@ Quality Dave, aka stokeballoon - Thanks for that info and very helpful link about your S3 brakes.

[RedRobin]

....

Just thinking aloud, but both the oem R32 and S3 rear brakes will surely have been designed to work on 'driven' rear wheels (be it Haldex or quattro).

Does this suggest that fitting them on the rear of the FWD Mk5 GTI may be overkill?

Please note that I'm only raising the question and not saying that this is the case.

Since i fitted my S3 rears the car is a joy to drive, the car feels balanced under braking, and the rear never gets "tail happy" under braking.  

i was asked by an independent engineer as to what brakes I have fitted, he was impressed by the overall feel of the car, and he has the pick of any braking system, being in the 'race preparation' enviroiment.

I therefore rate the S3 rears was the 2nd best mod behind fitting my RNS510.  

This is my opinion, and I would do the same again.

....But didn't you also fit S3 front brakes? So how are you able to judge the benefit of fitting only rear S3 brakes to a GTI/Ed30 as a mod?

[jabbalad]

In my opinion i would just stick some decent pads in the back, front wheel drive cars shouldnt use much rear braking... when your trying to do everything through the front wheels the last thing you want to do it to make the back too stable!

In a mid engine car it is possible to have more rear braking... because thats where the weight is!
For front engined front wheel drive its alwase going to stand on the nose when braking, no matter what suspension setup you have... so the front wheels have the most amount of grip to put the braking force through!!

at the end of the day when VWR (or any touring car team) build a car if there was an advantage to fitting huge rear brakes on a front wheel drive car dont you think they would use it?

Thats my part anyway, and i dont really need to justify this...

[QD MBE]

....

Just thinking aloud, but both the oem R32 and S3 rear brakes will surely have been designed to work on 'driven' rear wheels (be it Haldex or quattro).

Does this suggest that fitting them on the rear of the FWD Mk5 GTI may be overkill?

Please note that I'm only raising the question and not saying that this is the case.

Since i fitted my S3 rears the car is a joy to drive, the car feels balanced under braking, and the rear never gets "tail happy" under braking.  

i was asked by an independent engineer as to what brakes I have fitted, he was impressed by the overall feel of the car, and he has the pick of any braking system, being in the 'race preparation' enviroiment.

I therefore rate the S3 rears was the 2nd best mod behind fitting my RNS510.  

This is my opinion, and I would do the same again.

....But didn't you also fit S3 front brakes? So how are you able to judge the benefit of fitting only rear S3 brakes to a GTI/Ed30 as a mod?

Robin,

The way I judged is that the car feels far more stable.  Sat in the drivers seat, you can feel the rear being braked, front brakes do not give that feeling.  Thats how I judged.

[RedRobin]

Robin,

The way I judged is that the car feels far more stable.  

....I would suggest this is mainly due to the improved (S3 rather than oem GTI) front braking.

Sat in the drivers seat, you can feel the rear being braked.  Thats how I judged.

....Then you must have a much more sensitive arse than I have!

[Janner_Sy]

to be fair i think even if the rear discs only cope with 15% of the overall brake bias moving from 256mm to 312 discs and bigger pistons and pads etc will still make a huge difference in the overall stopping power available.

I also agree that if the brakes were increased on the rear as well as the front(albeit not to the same extent) then the weight transfer and balance would be much improved especialy if braking mid corner, which does happen sometimes. ie coming around a bend to find stand still traffic, or carrying too  much speed into a corner on a track and having to brake. both have happened to me before and ive felt the back step out a little.


However guys who have used the DS2500 on the std front 312 discs commented on the huge difference the pads made. So maybe that would prove to be more cost effective

[RedRobin]

I also agree that if the brakes were increased on the rear as well as the front(albeit not to the same extent) then the weight transfer and balance would be much improved especialy if braking mid corner, which does happen sometimes. ie coming around a bend to find stand still traffic, or carrying too  much speed into a corner on a track and having to brake. both have happened to me before and ive felt the back step out a little.

....Having to slam on the anchors extremely hard when coming round a blind bend has happened several times to me and I've been very glad to have the AP's - How my rear oem brakes behaved I have absolutely no idea! It was furthermost from my mind.

However, on a faster bend with open visibility or roundabouts, I tend to get all my braking done while the car is still straight even if I'm not going in as fast as I could be. At least with the Quaife it helps me get back on the power very early. But as you say, we can still get caught out.

However guys who have used the DS2500 on the std front 312 discs commented on the huge difference the pads made. So maybe that would prove to be more cost effective

....I'm looking forward (I think!) to seeing how just the DS2500 pads work on my oem rears at The Ring, if indeed I can feel a difference.

[DaveB@Vagbremtechnic]

In my opinion i would just stick some decent pads in the back, front wheel drive cars shouldnt use much rear braking... when your trying to do everything through the front wheels the last thing you want to do it to make the back too stable!

Thats my part anyway, and i dont really need to justify this...

Not necessary to justify anything mate, could you just elaborate on the bit Ive highlighted

[xxx_mojo_xxx]

Guys, whilst this is all good discussion - I can't help feel confused. 

I have a big brake kit arriving any time this week.  Should I also look at upgrading my rear pads, or go for the plunge and upgrade the discs as well?

[RedRobin]

Guys, whilst this is all good discussion - I can't help feel confused. 

I have a big brake kit arriving any time this week.  Should I also look at upgrading my rear pads, or go for the plunge and upgrade the discs as well?

....Personally I would get to know your front big brake kit first and then later think about your rears.

Unless you are going to be doing lots of trackdays you might only want to upgrade the pads on the rear. But take it all one step at a time so you can experience and learn from what each mod does.

Which front brake kit?

[jabbalad]

In my opinion i would just stick some decent pads in the back, front wheel drive cars shouldnt use much rear braking... when your trying to do everything through the front wheels the last thing you want to do it to make the back too stable!

Thats my part anyway, and i dont really need to justify this...

Not necessary to justify anything mate, could you just elaborate on the bit Ive highlighted

no problem, when your fast road or track driving in a front wheel drive car the only way it's going to go quick is if you can be the last on the brakes and first on the power, the only way to do this is to have the car pointing in the right direction as early into the corner as possible with the least ammout of steering input a possible... This doesn't work if the back end is too settled! (we have tried it) you can brake much further into corners with very little rear brake.
I see what your saying that the more even braking should mean better stopping abuility... And on mid engined or rear engined cars this is correct, but it's not really the right direction for front engined front drive cars! In my opinion of course.

[xxx_mojo_xxx]

Guys, whilst this is all good discussion - I can't help feel confused. 

I have a big brake kit arriving any time this week.  Should I also look at upgrading my rear pads, or go for the plunge and upgrade the discs as well?

....Personally I would get to know your front big brake kit first and then later think about your rears.

Unless you are going to be doing lots of trackdays you might only want to upgrade the pads on the rear. But take it all one step at a time so you can experience and learn from what each mod does.

Which front brake kit?

I've taken the plunge and gone for a big brake kit from HiSpec- 2-piece 360mm diameter discs, steel braided lines, 6 pot billeted calipers, 5.1 brake fluid, and some Ferodo DS2500 pads.

http://www.hispecbrake.co.uk/calipers.htm