Insurance company won't give you money for mods they will also use them against you if you mention them. I was in the insurance business for several years. I would not mention ANY modifications unless it's something trivial like wheels or suspension. They will be looking for any excuse not to put your claim in since Engine fires are rare.
They will likely ask you questions like when was the last time the car was serviced, where it was serviced, did it have any problems recently. Questions like what color was the smoke, what was the car doing prior to the problem, why did you keep driving ETC ETC. Be very careful what you tell them. My advice, less is more.
Although every insurance company is different from state to state, one thing is for sure, they dont like paying for claims.