What to look for and WHY: Coilovers

Jordo!

The biggest obstacle (other than price) is getting interpretable data.

Probably the easiest way around this is to find someone who is a good auto-x er in your make and model, with a nearly equivalent set up, and then buy what they have and set it about where they have it set. Same goes for tires, etc.

You might dial things in ever so less "aggressively" if it's street only, but its not as if folks in sports cars don't drive a wee bit more spiritedly day to day than the average driver (tho' hopefully in a safe and responsible manner...).

Failing that, the best OEM option on the table is as likely as not to be a superior (if over priced) set up that has actually undergone some real testing.

Just throwing down a bag of money on an aftermarket set up that has many options and configurations is useless if you aren't able to take advantage of it, and may even be counterproductive if you don't know what you are doing and/or the effect of a given adjustment cannot be validated (i.e., shock dynos, track day data, etc.).

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