Nate Tempest

Hi All,

So, I just picked up my '06 S2000 about a week and a half ago. Have taken it out to two local autocross events so far, and got my first #1 PAX yesterday. (Started autocrossing last October.) The car is amazing - much more predictable and easy to drive fast than the two cars I've autocrossed before this.

There's one thing I'm trying to figure out though. In other cars, under hard braking, I'm used to having the threshold level, and then if you push the pedal harder, you feel antilock kick in (the standard pulsing.) With the S2000 though, I've never felt the antilock kick in, nor do I lose traction. Rather, it feels like I can just push the pedal as hard as I want, and beyond a certain point, the car just doesn't slow down any faster. This is especially pronounced in situations where the car is light, like at the crest of a mound in the pavement, or to a lesser extent when on a downward incline. (Our autocross surface isn't particularly flat.) Since I'm never getting to the point where antilock kicks in, presumably I'm leaving some of the tires braking ability on the table. (I know I don't want to actually be in antilock, but rather in the threshold area just before it, but since I can't actually progressively trigger antilock, it seems unlikely I'm right at the threshold.) I'm assuming that if I really stabbed the brakes I could get antilock to kick in - I should try that actually - but I'm trying to understand what's happening in these situations. Am I getting antilock, but it's just much more subtle than other cars I'm used to? Or am I just not getting enough force on the brake pedal? (Is this why so many people upgrade to stainless lines?) Problem with the brake pads, so I'm not actually getting as much braking force as I should? (The pads Hawk HP+ with ~ 90% remaining, on stock rotors.)

You guys are all way more familiar with these cars than I am, so hopefully someone knows what I'm talking about here and what the cause is. Thanks!

Chuck S

Anti-lock brakes only activate when a wheel looses grip. Good tires may never do that, they just stop the car without skidding on lockup. And inefficient brakes won't clamp hard enough to lock the wheels with good tires. Stainless steel brake lines are mainly bling.

Stability assist On or Off?

-- Chuck

Nate Tempest

Yeah, I realize the point of abs is to prevent the tire locking up. In any other sports car I've driven though, the stock brakes are sufficient to lock up the tires, even on dry pavement, although I haven't had re-71rs until this car, so I'm sure that plays a role. Stability control is off.

So you're saying the force the brakes are capable of is insufficient to fully utilize the grip of these tires then. So, are there pads that will give me more braking force while still on the stock rotors than the hp+?

Chibo

There are many people running Hawk DTC60 level pads, or more, on stock rotors.

Nate Tempest

And will those actually increase braking force, or just resist overheating better?

Nate Tempest

What I don't understand is, the Hawk HP+ is at the very least a decent pad. I should be able to engage antilock with these in the middle of an autocross no problem, shouldn't I? Going to a full race pad wouldn't make sense for autocross since the heat won't be there. Maybe a Carbotech AX6? But from what I've read that's only supposed to be a slight upgrade on the HP+...

LeonV

Sounds like you have air in your lines. Have you bled your brakes? Is your brake pedal stiff or spongy?

djsilverjohnson

I second the recommendation to flush and bleed your brake lines. Our AP1 is on RE71R's (225/50/16), HP+ pads, stock rotors and oem brake lines. I've driven S2K's with stock pads and I can say the HP+ pads are much stronger and more linear. I have been able to jump on the pedal and engage anti-lock. When I really lean into the pedal without stabbing it's like I've thrown out the anchor.

Nate Tempest

Haven't bled the lines since buying the car last week, no. I definitely wouldn't call the pedal stiff, but it's not overly spongy either, except maybe in this situation when I'm really leaning into it and I'm just not getting any more braking. The brake fluid is a few years old, so probably a good idea to change it anyway. Will give it a try.

King Tut

Have you done a simple test of just going out on a road and doing 60 to 10 mph stops consistently in a row to see how the HP+ pads feel and if you can get them into lock up?