Generally,
Non of LEGAL modifications will void insurance coverage, inclusive of Engine swap, Bigger rims, straight racing piping, Upgraded brakes, tacho timers around the dash, sports steering, GT Wings.
You guys know wats i meant by LEGAL up there?, after any major modifications done to your car, you must reimburse back or inform the insurance agency about the status of your car. In my opinion, Converting EVO, GSR or turbo charged engine maybe a little bit expensive compared existing coverage of ure car as stock, this is because u have done alteration to factory standard car.
Any major modifications should be refered and informed to the insurance company for them to know, so if u involved in any bad incident or accident, they will be able to recover back your car. Because you have already informed them.
Insurance agency do allow modifications by refering to them.
Unfortunately, lets say u have crashed and totaled the EVO engine, they only able to recover your car as stock / factory standard back again.
The information i shared above is from my experience from one of my friend and its general.