Need a bit of advice on brake balance / following pad change.

I have just changed my rear pads from Mintex to Carbon Lorrain RCL5, rear brake bite is far better but now I am now suffering rear wheel lock.

WRX MY05 with about 340 HP Im using BC coilovers, std WRX 2 and 4 pots Godspeed 335*32 mm up front with either EBC Blue for road
(currently fitted). I use Ferodo DS2500 for the track. Road use tires are Hankock Winter 310s mfg date 2013 profile 215 45 R17.

To counter :

Should I need to use the Ferodo DS2500 all the time now ?
Does the WRX have a FR bias control somewhere underneath ?

As my driving style is unlikely to change after 30 years must I consider to fit a brake bias control in cockpit ?

Suggestions please

Thanks Ralph

 

Best bet is to speak to Ian or Ben at Godspeed, they will be able to give you the best advice. Good guys they are!

 

Sure , and I normally do , just right now coming up the Welsh rally both of them have better things to do.

The front are EBC blue, and need a fair bit of heat before they bite , ( cold bite is a bit of weak point on these ), The difference to the CL5 on the rear is so bad I nearly spun just pulling up at a roundabout from 30 mph.

Im going to put the DB7 Feroddo DS2500 back in at the Front and try to bring F-R balance back.

Anyone else had similar issues ?

Otherwise then reckon I will be looking for a **** to twiddle.

 

Get the rc5/6 up front should see you better or if your prefer ds2500 then match them at rear.
Problem is, you have better bite pads at rear.

 

Thanks Busta , makes sense.

But my budget is done til post Xmas I was hoping to save myself the dosh of yet another set of front pads for road work, however and I will try my existing DB7 sized DS2500 's again on the 335mm. I was trying to save them for track work as they are 185 a set.

The RCL5+ at the rear are noticably better than the Mintex ( provided you are still in a straight line ) and the bite is so strong that with the EBC blue upfront its bloody dangerous, so one or the other will probably have to come out again.

Many moons ago , I used to tweak my old Lancia bias with a valve under the car , I used a big Tarox set up and it really needed doing if it was wet as the rear would otherwise try to find its way to front.

Does the WRX have a similar valve underneath ?

Have you tried a brake bias yet on any of your track attacks ?

 

I had this problem on my classic with the old EBC reds and stock rears. Added to that the 3 channel ABS on classic scoobs did not like this one bit (basically left me with no brakes when braking hard or on slippy roads, even at 20mph - I found that out the expensive way courtesy of an Audi boot which stopped me). I initially thought it was the ABS at fault as I had good braking effort up until the Abs kicked in, then afterwards no brakes just the ABS pump buzzing away. I ended up pulling the ABS fuse and found the rears were locking before the fronts. New pads sorted it.

So as said, unfortunately you are going to have to buy a matching set of pads. I did strip and inspect the front and rear brakes and found the front pads had glazed, but even after deglazing and rebedding them, the problem returned. Fitted new pads problem never came back.

 

Thanks for info , I have subsequently added DS2500 FCP H 817 (Aston martin DB9 sized pads ) modifying ( file out ) the hole positions out and up.
To match the Godspeed 2 piece disc. The balance problem has been rectified
I guess the bite is now similar to the RCL5+ that I have on the rear.

 

The bite in dc2500 and cl are not same, surely.

 

Obviously not , but remember The 335mm's on EBC blue up front were originally doing all the work. I have Std disk of rear , which before hand were not doing much at all with mintex material. The CL5 's made a huge difference at the rear.
I have anyhow now tried it in earnest in dry and wet conditions but on Hankook Winter tires and for the moment anyway on these , Im well pleased with the balance after putting the DS2500 in. Im still thinking however that I have reached a point that I want to be able to decide for the conditions / choice tyre type that id like a balance control from inside the car. Back in 80's I used to take a little bit off the rear for wet / greasy conditions on the Lancia , so Im thinking that's my next mod in the spring time. noboby here seems to do this , Id have thought anyone often on track would be looking at it.

 

really you need a company that does race preparation for a bias valve-plenty in the uk could fit one -got a similar problem with my newage, firing the ABS on the front when the rears are hardly working at all. a bias valve could allow me to balance it up

 

Took a year for you to find this , thread revival ?

I have the balance valve under the Arm rest keeps it from the TÜV out of
sight. But a slight warning to any of you doing this on road cars.
Screw it up too much and you could be in trouble with Insurance /
bluebottles if you have a big off. But its a plus for anyone on a slighty
greasy or cold track / tires. Its been handy in the latest cold snap here.

 

yessss i,m slow what can i say lol

 

MadWrx,

Helps to be a little careful with the setting,
If you reach ABS on the front, be cautious dialing in balance to the rears. What may be fine on a dry track with fast curves can very quickly become all out of shape in slower curve, change of surface/temperature.

Last Saturday I left a little to much to the rears
then on a slow hairpin still ended up facing the the wrong way.

Nobody around, no damage, but still a dent to my over 50's ego.

 

fair comment very easy to change the balance too far when the available grip/traction changes-
i can normally activate the abs in the dry, big porsche brembos and relatively small 225 section tyres i reckon ... the brand new rear pads and discs havent worn at all,the rougher machining on the discs to assist breaking in pads is still entirely intact. rears are hardly working at all now it seems although still fairly warm after a good run so must be doing something.