I made a post on the racing section of s2ki talking about how my car was understeering and I’ve decided to get matching tires.

So in my search for tires I came across a thread about the right tire size for the rears. So knowing that I will be purchasing 245/45R16 for the rears.

Now my question is should I be sticking with stock front sizes (205/55R16)? Or should I go with a more aggressive setup of 225/50/R16?

I do use this car as a weekend car and autox and track days

 

Here's another thread to read regarding the AP1 stagger.

https://www.s2ki.com/forums/wheels-t...erous-1216330/

Unfortunately, i'm far less knowledgeable about 16" tire sizes for this chassis. 17" wheels and 18" wheels is where it's at for maximizing options and handling - understood that you're limited by the auto-x class rule sets for 16" wheels based on you having an AP.

 

I'd stick with stock 205/225 stagger for at least one set of tires for auto X. 245/45/16s are not a common size available for most popular super 200s and were only really used because the OEM factory tires ran wide for a 225/16s. Hold off of going nonstagger for the time being. Nonstagger is faster if you have the right supporting mods however SCCA auto X makes you do dumb things because of classing rules and the old B street meta from years ago was 225 all around on OEM wheels which are very muffin topped up front. Steering feel is reduced and as a newer driver you won't gain as much from this setup. If you want extra width maybe look at RT660 or A052 since they run very wide. Though now that I'm looking at Tire Rack it also looks like Yokohama A052 are one of the few tires that offer 245/45/16. If you were to go with this setup I'd go with 225/45/16s in front. The 50 ratio tire ends up being taller than the rears. Performance wise it probably doesn't matter too much but visually it'll look weird.

 

For autox, you can plus +-1 size your rims while keeping the width the same and i believe offset +- 8mm.
So for example if you have 16x7 with +50 offset, you can go to 17x7 with an offset of +42 through +58.

 

On AP1 16" wheels stick with the 205 & 245 sizes. Width of the front wheel would pinch a 225 on the front and look off, would make turn in worse as well.

 

Really shouldn't make tire size determinations until you figure out why a famously oversteering car is understeering. It ain't the rear tire size though. Wider rear tires will increase understeer.

-- Chuck