Hey i was wondering what is the highest class that still allows a bolt-in cage?
Ill be running a 86 corolla in IP3 but maybe later i might want to build the car up to be competitive in GTU so i was wondering if GTU allows a bolt-in or if it needs to be welded since it has so many more safety requirements.
Ideally the car stays street legal (barely) with a bolt-in cage.
Also I already have race coilovers on my corolla, is it still IP legal?
Can i leave the interior or is it a fire hazard?
Thanks

Coilovers should be fine, so long as they aren't remote reservoir, are not more than dual adjustable and can't be adjusted while you're driving.

You aren't required to remove your interior, but why leave weight that's so easy to drop?

For more info, download the SCCA GCR (http://www.scca.com/assets/2012GCR-updatedJune.pdf)and read over the rules for the Improved Touring class (the Improved Production rules we use are based off of the SCCA IT rules).  Rule 5.b.1 covers your coilover question.