307 283mm Brake Setup

[DRTDVL 4 1 Cars]

Hello Everyone,

 

I finally had the 205 out on the track for it's first event (5th in class, 15th overall - 60 car field).

 

I found lots of problems that will now need to be addressed and one is the brake temp.

 

With the 15's on the car and the 307 brakes i've noticed there is basically bugger all clearance between the caliper and the wheel and very little airflow to draw heat away.

 

We started with 28psi cold and the pressure after 4 laps was off the 40psi guage (rears went from 28 to 38).

 

I also noticed that the wheel was stupidly hot and you couldn't touch it for about 10min after the cool down lap.

 

I'll be working on a ducting solution baring that i'll need to swap to the s16 brakes or bigger wheels...

 

Just wondering if anyone else has run into this problem.

Edited September 17, 2009 by DRTDVL

[kyepan 291]

not wanting to sound like a silly willy, but with it jacked up is there any resistance to turning the wheel.. it could be simply a binding caliper.

[Rippthrough 98]

We started with 28psi cold and the pressure after 4 laps was off the 40psi guage (rears went from 28 to 38).

 

If the rears have gone up 10 degrees you can have a fair guess at the front's going up by about 15 anyway...

 

As above though, check the brakes aren't binding (with the engine on if you are running a servo!)

 

Ducting is generally always a good thing though - if nothing else it'll reduce your pad and disc wear, so it'll pay for itself in the long run!

Edited September 17, 2009 by Rippthrough

[DRTDVL 4 1 Cars]

kyepan & Rippthrough - The wheels arn't binding at all, it was one of the first things i checked.

 

Its been suggested that it's the pad compound i'm running, i'll shift to the other brand pads i've got (just road pads) to see if they help.

 

I'll look at getting a set of Endless pads for the car once a few other things get sorted on the car.

[mmt 15]

I run the same setup on my track car.

 

I run Tar-Ox race pads and do not have near the same temp issue. Start changing the pads, in sprint races ducting should not be needed.

 

You might find that drilled disks also would bring the temp down. I´m running Peugeot origainal disks and drilled 8mm holes in them my self. Works fine.

[kyepan 291]

i'm running the same setup, and use ds2500 compound pads, i was of the assumption that because they were so big they would be able to dissipate the heat just fine. Perhaps some home made ducting through where the driving lights enter is in order. Also what wheels do you have, as the space between the spokes has got to make a difference.

 

you could also try rigging up some kind of water injection system to work above a given temp.

 

when you say event, over what duration are you running, and how long between pressure tests?

 

granted mine is a road car.. but

[DRTDVL 4 1 Cars]

<--- not me but the same track...

 

 

event it was a dual car sprint, 1 warm up lap then 4 timed laps.

 

I was running the mi16 wheels on the front and some roh astrons on the back... all 15inch rims.

 

laps where about 1:26-1:27 in length. (was having massive issues with hooking third and the rear being too soft and lifting the inside front wheel)

 

I'm thinking that the heat is dissipating fine from the disc/caliper but it's dissipating directly into the wheel...

 

The pressure readings where taken about 5 min after we got off the track. we dropped the pressures down