Consider adding a Boss 302r/s ABS module. This will lock out the Advancetrac. ABS will still work.
Appreciate the suggestion, the whole advancetrac situation is fairly frustrating. I've looked into the 302r ABS module and it definitely will solve the problem, but based on my understanding will also light up the dash like a Christmas tree. I'd prefer not to have to swap the stock ABS module in multiple times a year for inspection/winter driving or even for heavy wet weather autocrosses.
No help for the christmas tree, but I can't think of a single situation on a wet autocross course (or track) that the S197 traction control would be better on versus off. I mean my 17 y.o. (at the time) daughter and I did the Grenada Pro Solo last May where it rained approximately 400 inches an hour for the entire weekend and it was moldy polished concrete that was almost tragic to walk on in the wet/river. The car was perfectly controllable on either the rain setup or race tires (RE71 at the time) with no TC. With a drag launch.
And the "race" ABS tuning is good in all conditions.
All that is a REALLY long way to say that whatever solution you end up with, you don't have to swap it out until winter.
You read above by DaveW and another and seeing the bucks you are spending the single one thing you need for CAM-C , or in my opinion , any Class is more rrrrrrrrrrrrrubber. Before you spend another dime, sell your rims you bought for $150 to someone for even more , get a set of 18x11s and then spend the money to acquire gumball, sticky rubber!! DaveW, Dave-W, AuteauX, and myself have seen Championship winning drivers lose in year in and year out because they second guessed the wrong rubber, but they did not er in the idea that they needed the most on the ground possible in almost every case.
You have tons of mods, spend the moolah in what will keep the car stuck to the ground next and before many of the other ideas!!!!
Just more advice from your friendly TMO members who are not know it alls , we just are trying to help you not make the mistakes we already made numerous times, ha.
You really need the right set and don't settle for 10.5s. Apex has plenty of Sales and frankly their normal price is not much more than what I have seen a few go for used. 315/18s are the winning size in CAM-C , they will fit with the 52mm offset Apex rims and a 25mm spacer. There might even be one or two more Tire Companies with that size out in 2021. We know Falken will have their new tire in a 315/18 relatively soon - Falken RT660. We have guys running this tire at the Solo Nationals site in Lincoln and they like them a lot better than the 615K -- better grip and steering response. You likely already know about the other 200 TWR rubber but you can always send me a PM ( conversation ) if you are wondering?