I could never understand how an average guy that MAYBE x-crosses a couple times in the summer thinks he can IMPROVE on a suspension, brake and tire combination that set the FWD record at the Nurburgring BOX STOCK?

 

Who doesn't want more? hell, look at your sig!

 

Touche!

 

 

http://spectator-racing.com/

May 15th with those guys. Sign up and come out if you can. The guys that run it are great. I was at one of their events last season as well.

I'll be there either in a Lightning or the Cobalt. Haven't decided for sure yet. The Lightning would be on Carbotech XP12 / 8's and Hoosiers. Cobalt on stock tires (I want them to die!) and yet to be determined pad.

Have you ever been to Grattan? It's pretty crappy but the track is really, really fun. A good blind apex and a pretty steep downhill off camber. Good elevation change, cool track.

It isn't hard to upgrade the tires from a grip stand point. A lot of sacrifices are made in OE tires for wet performance, tread life, ride quality, etc. Changing to a dry weather only tire would have instantly improved the ring time without doing anything else, guaranteed.

Brake pads for track performance are similar. Sure on stock tires you might be ok but on a stickier tire you can add more heat to the pads which can take them out of their operating range. It is another area where there are sacrifices made, mostly for low noise but also for lower dust. You can put on a better pad that will make it sound like a city bus but it will stop faster at higher temps if the tires have the grip to stop it faster.

 

I had a great weekend with Cobalt Friction XR1 front pads. I've always been a fan of CF. A bit expensive, but they won't ever crumble, or separate from the backing plate. Plus they're quite good on the rotors. Here are my XR1s have a long weekend at VIR:





I say you can easily improve the Cobalt SS suspension. First start with the biggest baddest rear bar that's available, the OTTP hardcore bar. The car is more neutral under trail braking, and throttle lift. After that, I'd say front lower control arm bushings. Finally Pedders and endlinks. The stock suspension is good, but still a compromise.

 

2 Piece rotors.......drool

 

Guys, I need some help...

Lost my brakes a few times so far at autox... and I dont know how to fix it.
Usually when I'm doing hard braking for the corner... the pedal will go down a bit more than halfway..
then stiffen up... and I dont think the tires were locked up, I cant hear tires skid.

I have decent street tires on.. running Hawk HP+ all around... new ATE Blue fluids.

Maybe rear HP+ is too aggressive?... locking up rear too early causing ABS to act up?

 

air in the lines maybe?" you tried bleeding them again?

It doesn't sound like the rear locking up cause what they call "Ice mode" and I'm pretty sure when that happens the peddle stays firm just doesn't stop you worth a damn.

 

I think thats what I got.. "ice mode"... hit the brakes.. stiff pedals.. not stopping.
But I'm wondering if it's triggered by rears locked up.. not to mention i was about to make a
hard right.

 

Are you turning off stability control? Not comp-mode, but actually killing it completely?

 

The rears must be locking up then. From what I understand when the rears lock up before the fronts the ABS thinks you must be on ice and reduces braking pressure. I have no idea how guys are working with this.

Still have the stock pads laying around you could throw on the back? After some searching I found this from a guy on rennlist:
" Turn off the engine while the car sits on a slope after the engine stopped let the car roll down hill, if you have servo support (vacuum) then the check valve which is supposed to keep the vacuum, functions. If you step on the brakes the first time and it feels like there is no vacuum support, then the check valve is leaking. This could be one reason why you did not have brakes available after a long straight because the check valve did not keep the vacuum while you had the throttle open, hope that makes sense."

everyone else just says either don't stab the pedel to hard or when it happens release and hit it again. easier said than done, I know.

 

Thanks jboogie!

I was stupid enough to throw away my stock pads... where could I get stock oem pads
for decent price?? LOL

How should the pedals feel if there is no vacuum?? Down to the floor?
I didnt have a long straight before the brakes went into icemode...it was a slight left into
a wiggle then brake hard for right turn... i broke hard but the car didnt stop.

here's a video of it:
http://www.youtube.com/watch?v=YVfRy0ffU8s

 

There's a seam in the brake zone. I predict that ABS was kicking in because of the uneven pavement, but there's no way to tell unless you can tell us that the pedal was kicking back. If you're cranking down on the pedal, and you're concentrating on other stuff, you might miss the kickback feel. You have ESC disabled right?

 

ESC off in all my runs.
I think I felt ABS kick backs... but very subtle compare to other cars I've driven before..
and normally pedal would be nearly to the floor before kick backs... not this one...

No ever here ever hit ice mode at autox events like I did?

Called a few dealers... they want way too much for rear pads...
Anyone here know where I could get rear pads at discount? Much appreciated!

 

Where in CA are you? If you're near me, I have some stockers for the rear of the TC you can borrow for an event.

 

Joe, Thank you for the offer!
I'm near east Los Angeles... but I really rather buy a set though... if stockers work out, I
like to keep it on the car, cost me to swap the pads.. LOL

 

nope , never hit ice mode. But I'm still on stock pads. Not sure what class your running, do you have an after market rear bar on it?

http://www.crateenginedepot.com/stor...P2299C192.aspx

^^ the best place I know of. Or you could just throw some junk on to try it out. http://shop.advanceautoparts.com/web..._1178020219___

 

D-Stock!! LOL D-Stock on street tires... it's a local class.

Hmmm.. using the part# found on another thread:#93190338
I was able to get it down to $77 shipped @ http://www.gmpartsdirect.com/
Still more than I like to spend just to try things out...
I'm also checking prices for HPS pads...

 

Are these for the track only? Or maybe I should say, are they suitable for something that will also get driven on the street more than just back and forth to the track?

 

Installed Hawk HPS in the rear... same thing happened... lost brakes going into corner.
Similar situation (just right after very short full trottle straight) and similar speed... maybe it's a vacuum
problem? I switch from full throttle to brake probably around 3500rpm just when the boost is about to
build up?

Anyways, more testing this weekend...

 

Damn, I wish "More torque_more HP" was still around, that GM engineer guy. He would know.

That's gotta really mess with your driving wondering if your brakes are gonna work each time you hit them.

 

Sorry, I didn't see this. Yeah, they're track only, but you can probably get away with driving to the track on them, as long as you don't hit the brakes too hard at night. I'm sure it'll throw sparks, and get you lots of unwanted attention :-)

Cobalt Friction generally only makes pads for track based cars and real race calipers. Go look what folks like LG Motorsports run on their World Challenge Vettes. It's the same compound that I'm recommending. By no means is it too aggressive. My rotors look great, and I can go back and forth between stock and the XR1.

 

I'm excited to finally give my XR1's a work out this coming Monday at Laguna Seca...

 

Oh ya.. also I got "Service ESC" on the DIC during my first run (ESC was turned off)... ever
happen to anyone here? I wonder if it has anything to do with me losing my brakes...