Coilover And Brake Q's

[bucket_boy101]

This isn't another which coilover should I buy thread.

I bought my 25GT with Tein coilovers on it, but I'm not sure what sort of Tein Coilovers, as I haven't had the wheels off yet for a closer look.

As usual they're really rough when I drive over any kind of imperfect surface, be it a speed bump (the narrow kind they put in shopping centre car parks to destroy suspension because who speeds in a car park) or a very minor change in road surface where bitumen has been relaid. I do know they're damper adjustable, but don't really know which way to turn the knob thing to make them softer. Can someone explain this to me?

Also the front driver's side makes a noise when going over any of the aforementioned surfaces, like fluid passing through the damper and the rear passenger's side squeaks when travelling over bumps too quickly for the suspension. Is there a way I can find out if I need to replace the dampers or springs on the coilovers?

With regards to my brakes, when I bought the car I was told the front pads would have to be changed, and then told that they were done as part of the roadworthy after I arranged for one. I suspect the brakes may not have been bedded properly, as they creek when I brake with low-medium effort. Is it possible to bed brake pads without knowing what sort of pads are in there, should I just keep driving my car and ignore the noise, hoping that the pads bed in, or do I need to take action and see a brakes and suspension specialist?

[warps]

Not sure about Teins specifically, but the adjustable dampers I've used have all been clockwise to increase damping effort (except some Konis that you had to compress, then turn the whole body - can't recall which way they went)

The dampers should be matched to the springs, so if you back them off too much, they might become bouncy. Better to overdamp a spring than underdamp - it might be that the springs are too stiff too (this is a Japanese thing where their tracks are like billiard tables and you can get away with very high rate springs).

Squeaking in the damper could be a seal rubbing on the shaft - some Inox or WD might clear it up, but this is often a sign of a drying seal that might be needing replacement soon.

Check the pads to see if they've been replaced. You should be able to see them with the wheel off (should have around 10-12mm of meat on the pad, maybe more if they're new). Again, brake pads can make various noises, so some are more normal than others. Bedding in brakes isn't as critical as it used to be - manufacturers often sinter the pads on a hot plate as part of the manufacturing process, so they should be fairly good out og the box. Of course bedding in will nearly always improve them, so can't hurt.

The basics of bedding brakes is the same for nearly all compounds. Heat them up repeatedly through moderate braking effort (say braking from 80 to 20), allowing about a minute to cool down between runs (but not coming to a complete stop if you can avoid it). You can increase the braking effort after you've done a handful of these, to the point that the pads might start to smoke (but don't apply full brakes at all - maybe only go to 60-70% braking). Smoke / burning isn't a problem, as it's just burning off resins etc. left over from the manufacturing process.

Once you've done this, let the brakes cool (preferably whilst still driving) and they should be good to go.

Whether bedding the brakes makes any difference is anyone's guess, without knowing what was done, and what the problem actually is.

Anything beyond the above, and you should take it to a reputable suspension and / or brake specialist. Not worth stuffing around with these things if you aren't confident.

Edited March 24, 2014 by warps

[bucket_boy101]

Does increasing damping effort make the ride smoother or rougher? Sorry for nooby questions, I really don't know much about cars, lol.

[KiwiRS4T]

Does increasing damping effort make the ride smoother or rougher? Sorry for nooby questions, I really don't know much about cars, lol.

Main problem is most likely the spring rate so damper adjustment won't help.

[niZmO_Man]

Does increasing damping effort make the ride smoother or rougher? Sorry for nooby questions, I really don't know much about cars, lol.

Generally, leads to harsher ride, but matched dampers to spring is better than having choppy suspension (over or under dampened).

Main problem is most likely the spring rate so damper adjustment won't help.

What he said.

[bucket_boy101]

Thanks guys.