Quote:
Originally Posted by CP 1///M
Just to bump this and augment my changes:
For this past track day I ran some 12mm spacers in the rear (effectively making them ET +10), and run 5psi more in front (45 hot) than rear (40 hot). I would say it seems to be doable but wondering if I ran out of adjustments as I probably can't go any wider in the rear (I might have tried 15mm but choosing 25mm to start was a mistake, nor milling those down 22mm help remove the rubbing)
I think with just the 12mm spacers and alignment unchanged I have increased enough rear grip to make car less snappy, and from the videos I would conclude that I'm relearning to drive without assists (TC off entirely) with more front grip than staggered and I should be able to have steering on more turns
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Oh my wow.
I think your first mistake is the rear wheel choice. Stock is 10" wide and yet you went narrower at the rear to a 9.5 " wide wheel and then at the same time you went to a .5 inch wider wheel than stock order to match the front as a squared setup ?
At the same time you also increased the front tire width by 20 mm as well ?
You have effectively reduced the rear grip of the car ( in proportion to the front ) with all three of these adjustments. This is what is causing your enhanced snap oversteer. The 1M already has a propensity for the rear end to step out and you have exacerbated this greatly by increasing your contact patch at the front and reducing it at the rear.
Adding the 12 mm spacers at the rear is actually pushing the rear wheels and tires back outward to where they should be originally, which does indeed help your situation, but it's a bandaid to fix the initial issue.
I am absolutely in favor of a square setup for many reasons .. most of which don't involve a stop watch. If you are racing , go as big as you can on both ends of the car although don't get crazy with the rear stagger.
For lapping day and HPDE work, the same is true.. put as much tire on the car as you can afford to ...... for me that generally means 275/30/18 " R " Tires on an 18X 10 square setup so I can put any tire on any corner for the best ability to maximize wear not only for each course but also within the weekend.
If you want to rid the car of some of the tail happiness at the rear ... add more tire to the rear of the car... if you intend to turn.. add more wheel and tire up front as well! I found that when I went with a 285/30 front and 315/30 rear on staggered 18 x 10 front and 18x 10.5 rear wheels.. the car puts down the power best but it does feel a bit more point and shoot however ... and those rear tires get $pendy.
Back to your setup... I think you've actually managed to make all the adjustments possible for the wheels that you have. You've added back some rear track. I wouldn't go with a wider spacer as that simply distorts the front to rear widths further. You've been adjusting tire pressures as well and those are really a fine tuning adjustment.
I really am not a fan of 9.5 inch wide wheels at all on this car. Indeed They are better than stock up front for grip. But you can also fit a 10 up front .. so why not ?! if you are tracking the car then let's actually make it perform.
Finally.. when on track, if you are committed to the corner in any car.. but especially the 1M... don't lift .. if you do.. you better have
really quick hands. I wasn't quick enough once, and I went for a bronco ride of a tank slapper and an OTE. Nothing but hurt pride , a lot of grass in a wheel, and video taken by a friend following
