[ajakejyt]

Hi there,

I have a set of 315mm Brembos ready to go on my 9-5 when spring comes around and I can mount my newly-acquired 18" Turbo X wheels. I've searched all over this forum, and haven't found a definitive answer on whether or not 9-5s require spacers when running the Brembo setup. I see that the 9-3s need spacers (despite 9-3 wheels having an ET41 offset), but two things make me question whether the 9-5 will need spacers or not: 1) the stock Cobalt wheels appear to have an ET42 offset (thus being slightly further inside the wheel wells than 9-3 wheels) and 2) the 9-5 run ET49 wheels, including Hirsch wheels, making me think the hubs and rotors on the 9-5 are further recessed into the wheel well away from the mating surface than on the 9-3. Taliaferro's site for the 9-5 Brembo kit also claims these brakes will clear "most" 17" wheels, whatever that means (Taliaferro is notoriously scant on details and curt in their communications).

Can anyone definitively say if my ET41 Turbo X wheels will need a spacer to clear the fat Brembo calipers?

Second, will I be able to run 235/45/18 tires on my 9-5 without rub? That's another topic I've tried searching for on this forum. I'm currently running stock 2.3T suspension up front but plan on dropping to Aero ride height with Koni shocks within the next year or so. Tons of people are running 40-profile tires on 18-inch wheels on their 9-5s, but nobody appears to have explicitly addressed 45-profile tires. I assume if I do need a spacer, then I'd definitely want to run lower-profile tires, but I'm not positive.

Thanks!

 

[qwikredline]

You may need to space the hub bearing out to center the caliper on the rotor. You will have to check in your installation. As for wheels clearing the Brembo that’s more an issue of spoke design than offset. Typically old style wheels have flat spoke design while newer style wheels have a convex design. Ion redline 17 wheels clear brembos. So do any 2008-10 cobalt TC wheels. Other 5x110 cobalt wheels do NOT clear unless a 5 m spacer is used. Wheel spacers are banned in many jurisdictions. The risk of using a 40 versus 45 aspect ratio tire comes down to gearing. You can reference your oem tire size on a typical tire chart ( 1010tires.com) and find out . Saabs generally are decent for inner fender clearance given correct tire and wheel Sizing and not lowering the car excessively. I find that Lowered cars suck ( cheap springs are generally junk spring rates and ride suffers

 

[ajakejyt]

Thanks, qwik - no worries on the lowering, I just want Aero spring rates all around (running Aero springs and Bilstein B6 in the rear). I also have a Tech II to adjust the speedo (and have done so, somehow, a previous owner set that my car was running on 16" wheels, even though it's a Dame and ran on 17" wheels from the factory). Guess we'll find out about spoke design and clearance...

 

[qwikredline]

You good then