[dre99gsx]

I know this is going to cause a stir, but here goes...

In my quest to get more corner-exit rear end grip on the turns, I wanted to run 315s rear / 275 front.

If you look at this image, you'll see that I am able to fit a 315/30-18 tire with 11" wide rim (et44 with 15mm spacer). To do this, I un-clipped the rear bumper and sideskirt, loosened the fender bolts and pulled the fender out about 1".

This causes the fender to no longer align in a few areas as you can see. I attempted to create a custom bracket to reattach the rear bumper. I haven't worked on the bracket for the sideskirt yet. You'll see I filled in the gap to the rear tail light with some plastic. There is a gap between the fender and the trunk.

Other than that, all of this is 100% reversible.

I'm actually not sure this will give me any improvement in rear end traction. My current track setup is 295/30 rear and 255/35 front, and they've been pretty sticky for my limited driving capabilities so far.

But, here are some things that I've been reading
1. Wider tire = same contact patch for the same weight, so I'm not really getting more tire on the road
2. Wider tire/wheel will be 3lbs weight extra. This is still LESS than an oem wheel/tire combo fyi.
3. Benefit or more tire = heat management: I can probably run a few more laps before the tires starts to get overheated or greasy
4. I could run slightly lower air pressure, giving me MORE contact patch
5. Break-away may be more abrupt, this may be a bad thing
6. Costs go up, it's another $150/tire for the rears
7. Longer to get tire up to temp. I noticed my rears are slower to get up to hot pressure than the fronts already with 295s.

Upside:
1. Allows me to run taller front 275/35-18 tire for more front end grip. If I run 275/35 with 295/30 rear, front tire is 16mm taller (or reduces my rake by 8mm making the car have higher ground clearance in the front than the rear)

So, I'm finding more negatives than positives to go through with this. I have no idea if I'll get more grip. My goal is to be on 100% throttle much earlier before the apex. But, so far, I have been getting on it earlier and earlier and these 295s haven't let me down yet.

I need convincing that this is not worth it. I'm not too thrilled about mis-aligned panels. I haven't tried this on the passenger side yet to see if the filler cap area prevents me from doing this... Do you guys feel I will see a benefit from this upgrade?