Brake upgrades for track use, rear discs, 4 pots?

[Iain]

Couple of questions about combatting some braking problems I experienced on my last trackday. Current setup:
Standard rear drum setup, all reconditioned/new 14,000 miles ago
256x24mm front ATE calipers, vented discs, various pads used

The problems I had were:

1) The rear drums stuck on after I came back into the pits
2) The fronts were fading after several laps. (I rigged up ducting pointing at the disc and tried to use the M1144s but it didn't work too well).

What I'm thinking of doing is:

1) Converting the rear brakes to discs/calipers and biasing them correctly, to give a more reliable braking when hot and hopefully not overheat and seize on
2) Upgrading the fronts to a larger disc and "proper" calipers, e.g. a 280mm 4 pot setup.

Questions... Is there anything I can try on the drums to stop them seizing on like they did? Also is there any chance I could upgrade to a "proper" caliper and still have fading problems?

[MK999]

What fluid are you using?

Ideally you'd get some temp indicating paint which comes in 3 flavours, green 430 orange 560 and red 670 iirc? and check what kind of temperature your discs are running at, most performance pads for steel discs should be about 4-500c and they won't start fading before 600ish so a combo of green and orange paint is ideal for checking that... drums I'm not sure on, who the **** uses drums nowadays

If you're running within ideal temps and still getting fading issues I'd point a finger at the fluid and a dab of green paint on caliper/lines could let you check temps there. If cooling is to blame you could upgrade to bigger discs and still get fading issues, but obviously you've tried a bit of ducting to solve the problem and it's not made it any better?

[Iain]

ATE Super Blue fluid, bled a little through the front calipers recently too so it was fresh before the day.

Issue with this is I need to put up with another trackday of fade before capturing some results from the temperature paint as I can't reproduce this kind of heat on the road?

I did try the ducting and it wasn't really an accurate before-and-after (Mintex 1144s faded badly without ducting on Donington, and faded with ducting on Blyton Park) but I didn't think it was that effective as you don't get that much speed up at Blyton.

Rear drums, well I don't really like drums anyway so a disc/caliper setup would be much nicer to maintain going forward I think.

[craig green]

I assume the drums seized because you applied the handbrake in the pits?
As for the fronts, proper fluid & pads should be fine, which the begs the question what engine/power have you got?

Simply going bigger (V6 288's) is a lot of extra weight as are 16v rear discs.

[MK999]

ATE Super Blue fluid, bled a little through the front calipers recently too so it was fresh before the day.

Issue with this is I need to put up with another trackday of fade before capturing some results from the temperature paint as I can't reproduce this kind of heat on the road?

I did try the ducting and it wasn't really an accurate before-and-after (Mintex 1144s faded badly without ducting on Donington, and faded with ducting on Blyton Park) but I didn't think it was that effective as you don't get that much speed up at Blyton.

Rear drums, well I don't really like drums anyway so a disc/caliper setup would be much nicer to maintain going forward I think.

Personally I would rather know what I was fixing than blindly changing things and hoping it fixes it, so I'd go for a diagnostic trackday over possibly multiple trackdays with the same issue. Were you running slicks at Donington as well? As slicks will obviously work the brakes a lot harder before they lose grip.

I'd be willing to bet the inertia in a drum setup is similar to or worse than that of a disc tbh! I have seen drums on fire before, where rear brakes shouldn't really get that warm on a Nova, most of the weight is on the nose before you even start braking. I agree on the front though it would be much better to get the 16v setup working effectively than just go bigger.

[uh60]

What rim size are you using ?

[toymex]

Iain i had issues with rear drums binding , i found it to be the self adjusters over adjusting due to the heavy use of brakes ,so i put a split pin through the adjuster to stop it winding the shoes out ,it seems to have solved the problem

[meritlover]

change the fluid, specify what pads you have tested, bin the idea of rear brakes, consider changing your driving style and or suspension to rely less on braking hard in corners. dont use the handbrake when the drums are toasting hot (they shrink as they cool onto the shoes locking them on).
how do the M1144s 'not work too well'?

Im with MK999, its probably fluid boil.

[phunkynova]

Try use Mintex 1155's or there is also 1166

[Paul]

The 256s aren't up to track day use IMO. Go to 280's.

When i did my track day i used 280s with cheapo pads, 1144 and st rear drums. I did snetterton which is a fast track and was out for 15-20 mins a time and did not suffer from any brake fade.

I'd guess you didnt do enough cool down laps as to why your drums over heated.