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Shade
02-02-2007, 10:35 AM
Has anybody experienced or is experiencing very spongy brakes on their Polo? This includes long pedal travel, almost to the floor sometimes?
I initially thought it my be a case of the brakes needing to wear in a bit but i am now getting concerned. I have contacted VW service and they are getting back to me, but i was curious to see if anybody else has had this problem.

clone_tk422
02-02-2007, 10:37 AM
yeah i am experiencing this as well.

Sometimes need to really slam the brakes on to get the car to stop as the brakes arent very responsive

is this what you mean?

Guy_H
02-02-2007, 10:54 AM
We adressed this in another thread on another forum, but this is what we have found with the brakes:

background - Our test Polo, fairly modified, pretty quick - see's a lot of track use.

Running at Sandown on stock brakes - 4 or 5 people up, experienced instructor driving - less than 3 laps out of the brakes.

Diagnosed - cooked the fluid. part of this was the heat transfer through the pads & calipers. Step one - a higher heat pad (in this case EBC Greenstuff) and a "race quality" fluid (in this case prospeed 610 from Martini in Melbourne) - much better pedal feel, much more fade resistance.

Next step was a larger diameter rotor (Audi TT 225) - more leverage (same size calipers - different caliper to locate the caliper out further) - more stopping power & less fade again.

A big issue we have on the pedal feel is the firewall flex - the master cylinder / booster is bolted to a firewall panel which is bolted in. Measuring the flex on our car we can see up to 15mm deflection when pushing the pedal down (look at the brake booster when having someone sit inside & stomp on the pedal - you will see it clearly) - This is a big factor in the pedal feel and an issue we have not been able to address as of yet - to really get access to this area we need to drop the engine out before we can look at firewall bracing.

We are also going to Alcon brakes on our polo now, we have gone beyond the limits of the TT setup :)

Shade
02-02-2007, 11:22 AM
Yeah, that's was talking about. Still waiting to hear back from VW but spoke to the salesman and he said that is not right and if i remember correctly this was not evident on the 2 different demo cars i drove before i bought the car.

I don't think this has anything to do with heat transfer or cooked fluid because it's been like this from the day i got it brand new, no matter if it's cold or hot.

Shade
02-02-2007, 12:09 PM
Looks like it going back to the dealer today for them have a look.

VWDUDER
02-02-2007, 12:45 PM
Looks like it going back to the dealer today for them have a look.

Yeah getting kind of the same - would like to see what your dealer says.

Shade
02-02-2007, 01:13 PM
Make that Monday, can't leave work early today, forgot i had an appointment this arvo. Bugger!

VWindahouse
02-02-2007, 07:17 PM
We adressed this in another thread on another forum, but this is what we have found with the brakes:

background - Our test Polo, fairly modified, pretty quick - see's a lot of track use.

Running at Sandown on stock brakes - 4 or 5 people up, experienced instructor driving - less than 3 laps out of the brakes.

Diagnosed - cooked the fluid. part of this was the heat transfer through the pads & calipers. Step one - a higher heat pad (in this case EBC Greenstuff) and a "race quality" fluid (in this case prospeed 610 from Martini in Melbourne) - much better pedal feel, much more fade resistance.

Next step was a larger diameter rotor (Audi TT 225) - more leverage (same size calipers - different caliper to locate the caliper out further) - more stopping power & less fade again.

A big issue we have on the pedal feel is the firewall flex - the master cylinder / booster is bolted to a firewall panel which is bolted in. Measuring the flex on our car we can see up to 15mm deflection when pushing the pedal down (look at the brake booster when having someone sit inside & stomp on the pedal - you will see it clearly) - This is a big factor in the pedal feel and an issue we have not been able to address as of yet - to really get access to this area we need to drop the engine out before we can look at firewall bracing.

We are also going to Alcon brakes on our polo now, we have gone beyond the limits of the TT setup :)

So what will a set of Alcon set me back mate? Do they do a complete set ie. front and rear discs, callipers, lines etc.? What size are the discs and are drilled and slotted or just slotted. Very keen, cheers :) P.S. hi, first post!

Guy_H
02-02-2007, 08:58 PM
Hi - no probs - good first post (hope you are enjoying your Polo)- Alcon's are awesome, but so is the price.

The 13" (355mm) set with a 28mm width rotor is $4500 - all Alcon sets are priced similarly wether you have a rex, hsv etc - the technology of the caliper & disc is what you pay for (same as 70% of the V8 supercar field use). The Monoblock calipers have the correct pistin sizing for the 19mm Polo mastercylinder & bias.

We can go to 34mm thick discs, but we don't think we will exceed the heat capacity of the 28mm ones on the Polo (will know by the end of the month!)

Once you try them, you become addicted to the stopping power!

The TT setup is pretty good (332mm) but it has its limitations when you start to hit the track, we found this out recently :???:

you are welcome to take ours for a spin if you are up this way!

Timbo
03-02-2007, 05:36 PM
For normal road use, I can recommend the EBC GreenStuff pads as an 'OK' improvement. I'm currently trying to source some Ferodo 2500's as a hopefully better solution...will wait to see if they're available. Another thing to consider is removing the front backing plates to improve heat disappation. Thus far, the original fluid seems OK, but I'll probably replace with a competition fluid soon.

I have tracked mine, and found the brakes to be just adequate, but much less effective than my previous car. Certainly, I will probably look at bigger disks and caliper -- either S3 (which fit fit under the 16") or R32 brakes (need 17" rims). Sorry Guy, but $4500 on a set of Alcon is way OTT -- this is a $27k car! If we can source something similar to S3/R32 for around $1200-1500, that'll sell like hot cakes!

So, incremental improvements, and I'll have to learn to drive within the car's mechanical limits on the track :( . On the road, however, it's fine :D

VWindahouse
03-02-2007, 07:36 PM
Hi - no probs - good first post (hope you are enjoying your Polo)- Alcon's are awesome, but so is the price.

The 13" (355mm) set with a 28mm width rotor is $4500 - all Alcon sets are priced similarly wether you have a rex, hsv etc - the technology of the caliper & disc is what you pay for (same as 70% of the V8 supercar field use). The Monoblock calipers have the correct pistin sizing for the 19mm Polo mastercylinder & bias.

We can go to 34mm thick discs, but we don't think we will exceed the heat capacity of the 28mm ones on the Polo (will know by the end of the month!)

Once you try them, you become addicted to the stopping power!

The TT setup is pretty good (332mm) but it has its limitations when you start to hit the track, we found this out recently :???:

you are welcome to take ours for a spin if you are up this way!

Alcon seems to be the way to go! Spoke to a WRX sti owner at the dealership today with some, and he raved about them! Would definately like to take you up on that test drive offer! Cheers :)

Guy_H
05-02-2007, 08:06 AM
Yep - I agree, the Alcons price point on a car such as the Polo make them difficult to sell, mind you, we hope to have our Polo to 260kw a little later this year, so they would be a good investment.

The S3 type upgrade SHOULD be the one for fast street use / ocasional track use (with good pads & fluid) -

A hint for that upgrade, its the caliper carriers that are needed instead of complete calipers, only problem is the carriers are damn expensive too!

Guy_H
05-02-2007, 08:07 AM
P.S. - we will be looking into a firewall brace in the future as well :idea:

VWindahouse
05-02-2007, 07:02 PM
P.S. - we will be looking into a firewall brace in the future as well :idea:

Nice work and please keep me up to date with all the progress in the future!

pologti_oldfart
05-02-2007, 08:09 PM
I fitted EBC "Greens" to my car (only on the front) and although they have improved the feel and stopping power they squeal like nobody's business! I have done over 10,000kms on them and they still squeal. Looks like some shims may be in order!

Shade
06-02-2007, 02:50 PM
Took it back to dealer today, they admitted that it felt a little soft and they bleed the brakes. But it has only marginally improved it and they say that's how it is. A little dissapointing. Guess a set of Green stuff and maybe different fluid may help. Can anyone tell me the rough price of a set of Green Stuff?

Timbo
06-02-2007, 04:14 PM
EBC Greens -- part number is DP21479, and they are actually the upgraded pad listed in the EBC catalogue for a Skoda Fabia (and a couple of other VAG platforms). They cost around c.$150

I've not had any squealing problems, but both pologti_oldfart and another Pog owner I know do mention this. :?

shaneth
06-02-2007, 05:26 PM
did pologti-oldfart machine the discs when putting on the new pads

pologti_oldfart
06-02-2007, 11:30 PM
The discs were machined before the pads were fitted. My mechanic said that shimming the pads will fix the squeal.

evorobin
06-02-2007, 11:35 PM
Greenstuff pads should be $150 and ATE blue fluid is $40/L

shaneth
12-02-2007, 04:45 PM
Are there any disc's that are drilled and slotted on the market yet as a direct replacement for the disc's on the polo??? How would these fair with the green stuff? From what i have heard they improve braking quiet a bit.

Timbo
12-02-2007, 05:10 PM
Check DBA (www.dba.com.au)....you might have to call them, but if anything's available, they'll know

shaneth
12-02-2007, 05:17 PM
yeah ive got a friend in that industry. was just putting the question out there, everyone seems to be talking changing to r32 brakes or better and spending a fair bit of money. Thought it might be a cheaper option. Personally i dont find the brakes to bad. when i did my first mountain run they felt a bit spongy at the end, i was using them quite a bit but now im use to the car i havent been relying on the brakes hardly (mostly engine deceleration). And if you ask Dr Spine i dont go slow through the hills. :P just my 2p worth

Timbo
12-02-2007, 07:38 PM
The critical issue with better (bigger) brakes is where to mount the caliper and, if you go to R32 brakes, the need to fit 17" wheels. Together, that's a lot of money.

There's a couple of us trying to fit and test different pads. Ferodo 2500's are available, so they're the next step up after EBC GreenStuff.

Shade
02-03-2007, 12:47 PM
Popped into a Brake place today to get some pricing on some bits; EBC Green stuff, Motul RBF 600 or Martini Racing GS610, SS braided lines and maybe slotted rotors - flushed & fitted. He is going to get back to me later today.

shaneth
02-03-2007, 02:11 PM
Good work SHade. Id be interested in the price as well.

Shade
06-03-2007, 02:35 PM
The brake place finally got back to me (after chasing them up 3 times) and the prices are as follows this is allowing for labour as well (allegedly). And the prices are approximates untill all part sizes can be confirmed.

Green Stuff - Front and Rear sets : $330.00
Custom SS Braided Lines : $100.00 per corner
Flush and replace fliud (Motul RBF 600 or 5.1) : $45.00
Slotted Rotors -Front : $120.00 to $180.00 each
Slotted Rotors -Rear : $90.00 to $120.00 each

Worse case all up: $1330.00 ........EEEP!:(

Going to drop the car around to them to measure up everything and finalize prices next week. At this stage i may only do the the Pads, Braided lines and Fluid, might wait till i kill off the factory rotors before going slotted and so my misses doesn't kill me for spending over $1300. ;)

Will let y'all knoiw what happens next week.

VWindahouse
06-03-2007, 06:46 PM
Nice work there Shade! What brand are the rotors you were quoted on?

Shade
08-03-2007, 12:37 PM
I am still thinking that there is something not right with my brakes. The soft spongy feel, the long pedal travel and now i have noticed that there is hardly any wear to the rear rotors. I can still see lots of rust spots. Is it just me or is this normal?

GTIJNR
08-03-2007, 06:33 PM
I am still thinking that there is something not right with my brakes. The soft spongy feel, the long pedal travel and now i have noticed that there is hardly any wear to the rear rotors. I can still see lots of rust spots. Is it just me or is this normal?

its just mean that the rear pads not bed in properly... the front pads do most the work, so the rear will run in by the time u replace the front lol.