Brakes unless at high speed - what to tackle?
 

Well, I found out luckily without any loss that the brakes on the FR-S are no good at highspeeds. At ~130kph and higher they feel non-existent if you need to stop the car and anyone who doesn't engine brake hard is in trouble.

Pads felt greased! Haha. So - what's the first couple steps that will improve this particular sort of braking?

Was this the first time you have ever fully used the brakes since you bought it?

Heh, this is kinda strange. The car will feel a little different under high speed braking than low speed, but it shouldn't feel anything like "no brakes". 130kph is only 80mph, that's not crazy high speed by any means, but we need more info...

What were the circumstances, were you out cruising around, on twisty mountain roads, on a track? How many miles are on the car? Was the pedal soft? Was ABS activated? Were you actually pushing the pedal firmly or it just didn't brake as hard as you thought it should?

Its possible the pads were glazed, fluid boiled etc... If you really need an upgrade, better pads and fluid would be the first step. It's the final step for most, the stock braking system is pretty solid until it's pushed to its limits, which should only be achievable at a track, not on the street.

engine braking does not change the acute stopping power at all

His point is that engine braking helps bleed speed. He said nothing about engine braking making the brakes better or worse.

Speed is not the primary concern with brakes, it is heat that you need to worry about. Just going 80mph and stepping on the brakes should be no problem for the stock brakes. If you did something to get them hot (riding the pedal, repeated hard stops) they will be equally weak at any speed until they cool down to regular operating temperature. Higher speeds will obviously heat brakes up faster, so there is some speed at which the stock brakes will no longer be effective, but they should have no problem with 80mph during regular driving. I think you need to give us more information about the circumstances and what happened. Were you using the brakes a lot before this happened? Were you running summer tires in cold weather? Did the ABS activate?

I had the same thing on a WRX once at high speed but only because the brakes were cold. Cruising at 120kph for 20min without touching the brakes and then went flat out on a secluded straight stretch. Crested a hill at 230kph and saw 80kph signs and an intersection but had no brakes, the pedal just hummed under my foot. I thought I knew the road but got it wrong! I changed down, got the brakes back at 180kph and took the bend fast.

If it was like that at 130kph on cold brakes I would take to the dealer under warranty.

my point is that if your brakes arent enough to stop the car, your engine wont save you. he said if you dont engine brake you are in trouble (or something to that effect). if you get yourself in trouble, and its not from overheating your brakes, engine braking is not going to help you at all. actual brake systems have not been the bottle neck of stopping power since the sixties.

Yeah engine braking on a RWD car with a 2 liter engine is not going to provide much stopping force at all.

Brakes are so easily and cheaply upgraded. A good pad choice and fluid change alone will make a night and day difference.

You can go even above that and do rotors and lines, remove backing plates for extra cooling. So many options on the stock system to get improvement.

Start with pads and fluid. We noticed a huge increase there. We recently added our stage 2 package to our car for this weekends time trial.

http://ft86speedfactory.com/images/brakeupstg2.jpg

With 12.5:1 compression a 2L will provide similar engine braking to a 3L with 8.5:1 and be a lot lighter vehicle to stop too.
When you lose your brakes, engine braking is fantastic, almost as good as the hand brake if you don't lock it up and more stable.
I tend to use the engine to slow down and enjoy the gear changes, then use the brakes for coming to a stop only. That way you are less likely to get caught out when things go wrong.

Yeah but he said

If you are engine braking hard, you are already in trouble. If you try to "engine brake hard" in a RWD car you will spin. When you engine brake you are just braking the rear wheels, combined with the fact that you are shifting the weight forward by braking, you're not going to get much done that way and you'll end up in a ditch. Sure it can be done to bleed off some speed on the highway or coming to a red light but the idea of "engine braking hard" is pretty foolish.

http://en.wikipedia.org/wiki/Lift-off_oversteer

My brakes feel fine (for a few laps anyways with stock pads) at higher speeds. :shrug:

Which brake fluid did you guys use?