[AutoXJunkie]

So, I was out carving up some twisties tonight, and was sort of delving into how the WRX handles while trail braking. Didn't take long to find out that is doesn't like it much, at least not while completely OEM. I dove into a gentle right followed by a sharp left- prime territory for trail braking- and even at a relatively conservative speed and angle, as soon as I applied pressure it felt a lot like the front clamped down a lot harder than the rear, resulting in a little bit of (seemingly) brake bias-induced snap oversteer. Whee- I'm glad I decided to test conservatively first! It was only a little wag, but if I'd been pushing it, it could have gotten out of hand real fast. (Please note, I'm pretty familar with trailbraking on these roads, especially that turn, and I know the WRX is the only sports car I've had this problem with.)

So, am I imagining this, or does anybody else feel there is significant front brake bias from the factory? Honestly, it didn't feel like a tire problem- it was just that the front was stopping faster than the rear. Subaru shipping it with front bias would sort of make sense if they were having problems getting their stopping distances down with the extra weight. More front bias that would generate better straightline brake test numbers for the magazines, but at a cost in the turns.

I'm also wondering- if I'm not imaginging this effect- if this could be contributing to some of these wrecks. You know, people get spooked in a turn and tap the brakes- never a good idea if you're not used to doing it smoothly and carefully- and with significant front brake bias, you've got even more of an instant spin than you would in another car.

Anyone else notice this? And how can we correct it with the OEM system? Rear pads that bite a little harder, maybe??

 

[thechickencow]

Are you sure its a brake bias issue rather than a weight issue. I've always attributed it to that, rather than brake bias. I've noticed very similar things though. Now that I'm used to the way the car handles I don't notice it really, since I realize how the weight transfers under cornering.

tcc

 

[AutoXJunkie]

Are you sure its a brake bias issue rather than a weight issue.

I don't know, man, maybe so, but it seems to me that if weight were an issue, it'd be in the transition, but, most of the weight had already shifted at the time I experienced the wiggle. Then again, I guess maybe it could be brake dive- hit the brakes, the body pitches and unloads the rear wheels enough to let them drift out a little. But honestly, it didn't feel like that at the time. I've gotta admit that's a possibility, though.

Any other thoughts?

 

[bedabi]

Good observation.

I have the OEM four-pot front brakes. I don't think they necessarily stop the car any faster, but they do modulate better, and with new tires, the car definitely stops better anyway.

You're right, the WRX (at least on stock suspension) does NOT like to trailbrake. With my Cusco swaybars on the max setting, attempts to trailbrake would induce 360 turns! While autocrossing, of course. Instead, I have to STAND on the brakes before even turning the steering wheel, then apply gas into the turn. Because it takes a moment for the turbo to kick in, I'm not in danger of too much torque while turning.

Personally, I don't think it's so much a front brake bias as I do the soft springs we have. I've seen WRXs with coilovers and stock brakes and pads not behave the same way.

Here's a nice pic of me on three wheels!

 

[aussieinstlouis]

sweet picture!!

 

[Trypsin]

I know when i try to trail deep deep into a corner i have a sever anti-lock issue, the second those thinks come on all pedal feel is lost. The only way i can get it to work right is to jab the brakes hard when i first start to turn in to get the rear unsettled then lift off the brakes a bit when i put more stearing in. i do have a wagon though. I think to much front bias could exagerate this phenomena.

AXJ, how are you enjoying the move from miata to wrx, thats the same switch i made.

 

[GV27]

I think it might just be a weight transfer thing. My car has a bit of a tendency to step out during trailbraking, but not to the extent that it threatens to spin me even with my 24mm bar in back. So I was trying to figure out what the difference is. My first thought was that my old car had a big time tendency to step out under braking due to the settings I used to overcome the FWD understeer tendency. I was used to catching it all the time. But I experimented and that doesn't seem to be the case. Then it hit me - I have a Wagon with a better weight balance. So maybe it is a weight issue.

As far as the ABS goes, mine works great unless I hit a bump just as I'm applying them. You might just be trying to run too deep Trypsin. Too much brake with too much steering and yeah, you'll activate the ABS (or lock up without it). I know in the snow I always feel like I'm leaving some braking on the table when the ABS kicks in. But I'm probably not. It's just that I don't have total faith in the ABS whereas without it I KNOW there is no grip left when I lock up.

C

 

[trhoppe]

Try to get some coilovers and you can balance the weight transfer a bit with springs and corner weights. I almost lift a front tire Granted this wasnt under full braking.......but........

 

[Trypsin]

Nice pic. trhoppe thats a great shot.

GV27 your probably right, i think my main issue is the re92s in conjunction with being to agressive on the brakes, they are just about gone, so i will get some better ones. And practice, practice, practice.

 

[ScoobySteve]

So, am I imagining this, or does anybody else feel there is significant front brake bias from the factory? Honestly, it didn't feel like a tire problem- it was just that the front was stopping faster than the rear

Well if this is any indication, I changed my front pads yesterday - they were literally down to nothing after going on the track the day before. The rears still had almost 8mm of pad thickness left.

 

[GV27]

Yeah, but that's typical. The fronts will always work harder and will always (unless you're into spinning out!) be biased towards the front since most of the weight shifts up there. In my CRX I've changed the rear shoes twice in nearly 200k miles. Front pads probably 8 or 10 times!

Chris

PS. 1000th post for me. Yea me!

 

[ScoobySteve]

Good clarification, Chris. Hey, very nice new avatar.

 

[stilesg57]

Sorry to take this in a new direction as I do feel this topic has been well addressed, but try the Whiteline Anti-Lift Kit. It's only like a hundred bucks and man is it nice! I just installed mine a few days ago, and my WRX feels like a different car. This keeps the nose planted under acceleration and cuts the front dive under heavy braking by more than half! I also noticed turn-in was greatly increased, and there is a general feeling of more 'taughtness' in the front end. All in all, besides tires/wheels this mod has made the biggest difference in the suspension, even more than the swaybars.

BTW...

Suspension wise I have Front Cusco 21mm swaybar, Rear Cusco 22-24mm adjustable swaybar, Eibach pro-kit springs, Whiteline Anti-Lift Kit, all riding on 225/45/ZR17 pole position SO3s. I can say without a doubt that the Anti-Lift Kit has had more overall positive handling effect than any other suspension mod, excepting the SO3s. If you feel too much front bias on your braking (actually too much front dive) try this - you won't regret it.