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Just wondering if anyone else has had problems with brake lock ups on the track...and some times the street.

I have always found on my NA6 with all brake configurations...ie standard NA6 rotors calipers, slotted rotors calipers hawk hp+ and now NB 1.8 (2002 model I think) brake upgrade with dba slotted fronts hawks (motul fluid) that on the limit there is a fine line between maximum braking effort and locking up the left front.

I recently had to brake hard on the road (to avoid a retard pulling out of a side street without looking) and the brakes were cold (ie not up to temps that you would get at the track) I locked up front left again.

I have successfully flat spotted a couple of dunlop do1's (always front left) which is a pain.

So, question: why would there be a tendency for front left to lock.
how to avoid it (becides driver error). Would there be a bias issue. would braided lines help...retro fitting abs?

Lock happens with all size tyres/rims (street standard 14x5.5, track 15x7 205's R specs).

Cheers. ideas welcome.

Maybe overhaul both front calipers - the left might be marginally more efficient. Otherwise, you'll just have to modulate that right foot.

Perhaps your rears aren't biting as hard as it should, and thus you're pressing the pedal that much more harder, and thus your fronts are working extra hard to compensate.
I think there is a way to adjust the rears as it was done on the last dodgy day up here, but I wasn't paying attention.
Someone here will definitely answer with something more useful, but if not, give Jules a PM.

Check for any faults (eg seized calipers/slider pins)

If you have adjustable suspension, check your corner weights, or for a sagged spring.

Work on your skillz (squeezing and modulation).

Brake lines won't help. retrofitting ABS would be, but it's a monster job and not worth doing (just buy a car with it fitted)

yeah...probably driver.

Sliders/pins...probably not - as happened with both NA6 and NB8B setups..ie different callipers etc.

Have never had the car corner weighted though. Got kings/konis all round, nothalene bushes, adjustable sway front...

Have been noticing a bit of a knock in the rear left lately....at first I thought it was my hardtop moving a bit on the rear housing but am now tending to lean towards rear shock/bush. Handling still good though...hmmm.

Dont get me wrong...braking performance pretty good specially once up to temp....you know after a couple of hard braking corners at the track when you can feel the small vibration from the slotted rotors... I love that.

My question really is why the front left only.

Thanks for your input people.

It is usual to have the front left lock first because the driver sits on the right. The front pair should always lock before the rears. The driver's side front should lock very soon after the front left.

I've just had my car out for a run and did some big stops to check everything out. Front left locked first. I released brake pressure before finding out if the front right would lock too. I have a temporary set of terrible Nankangs (sp?) on my car.

M

My NB had this issue also, however, with new pads and a bit of grease on the pins the issue went away.

As JBT mentioned, the issue, if any, will be with the drivers side front caliper as your passenger side is clearly working fine!