Upgraded Brakes = nagging ABS?

[xxBrun0xx]

So need some advice. Recently upgraded brake pads to Stoptech Sports, Rotors to Centric blanks, Stoptech SS brake lines (front and rear), and Motul DOT 5.1 brake fluid. After installing and bleeding everything, I noticed on the first drive that the ABS kicks in way more than on the OEM setup. Anything over ~20mph, if I push pedal down half way, ABS kicks in. This happens way before the tires lose grip and doesn't seem to change with different tires (Swapped out 1 season old Pilot Supersports to brand new Nokkian Hakka P2's yesterday, ABS seems to kick in at the same point).

I don't see any brake fluid anywhere and car doesn't appear to be losing any. Might there still be air in the lines? Pedal feels about the same as stock (I was expecting it to be stiffer with the SS lines, more aggressive fluid, and more aggressive pads). Any ideas?

[ryoma]

I don't think having air bubbles in your lines would cause the ABS to engage sooner. if anything, it would make it harder to engage ABS I believe. are you sure your ABS wires are good? it doesn't sound normal to have ABS kick in that early.

btw, I have never heard of Nokkian... are they a good brand? it might be bad tire grip or something that is tricking the ABS

[gramicci101]

Originally Posted by ryoma

btw, I have never heard of Nokkian... are they a good brand? it might be bad tire grip or something that is tricking the ABS

Nokkian is an outstanding winter tire. Much better than what most of the big tire manufacturers come out with. That said, winter tires don't have the best traction when it isn't winter.

[xxBrun0xx]

Originally Posted by gramicci101

Nokkian is an outstanding winter tire. Much better than what most of the big tire manufacturers come out with. That said, winter tires don't have the best traction when it isn't winter.

My pilot supersports were engaging ABS early as well. ABS line was not touched during install, so I would be surprised if that had anything to do with it.

Maybe it was because it was cold (~50F) when I tested brakes on pilot supersports, they didn't have as much grip as usual? Felt like ABS was kicking in way before I would normally lose grip, though.

[ryoma]

Originally Posted by xxBrun0xx

My pilot supersports were engaging ABS early as well. ABS line was not touched during install, so I would be surprised if that had anything to do with it.

Maybe it was because it was cold (~50F) when I tested brakes on pilot supersports, they didn't have as much grip as usual? Felt like ABS was kicking in way before I would normally lose grip, though.

sounds like the temperature is the culprit to me.

[Pat]

Originally Posted by xxBrun0xx

This happens way before the tires lose grip

I would be shocked if ABS is activated before the tires lose grip. I'm not saying it's impossible, but if that's actually the case I'm very interested to know how that could happen.

[churchx]

By chance tire setup is not staggered with different diameter front-rear so that wheel sensor may wrongly signal "wheel slippage"?
Other theory "swapped brand new + winter", less grip on normal dry tarmac when not cold (or if cold, then due ice less overall grip) + new tires not yet broken in and still having lubricant from manufacturing/storing process? Check if things won't change for better after 500km on them passed.

[xxBrun0xx]

Originally Posted by churchx

By chance tire setup is not staggered with different diameter front-rear so that wheel sensor may wrongly signal "wheel slippage"?
Other theory "swapped brand new + winter", less grip on normal dry tarmac when not cold (or if cold, then due ice less overall grip) + new tires not yet broken in and still having lubricant from manufacturing/storing process? Check if things won't change for better after 500km on them passed.

I don't run staggered setup on summer or winter wheels. I also swapped brakes over about a week before swapping the snows on. I messaged FT86speedfactory on here, they said to try bleeding the whole system again just in case there was a pocket of air somewhere. I'll give it a go tonight, I've got some ATE DOT4 fluid laying around I can use.


I drove the car hard last night and noticed that I could break the snow tires loose while breaking fairly easily. However, when I had the pilot super sports on, could not burn rubber while breaking no matter how hard. With colder weather coming, may be a while before I can test again with the summer tires, but once I figure out what's going on, I'll update this. Thanks for the suggestions, guys!