Drivarotor

I was running some errands the other day and I had some hot start problems. After leaving my last destination the 7 did not want to fire. Then when it did it ran as if it was on one rotor only. After about 10 seconds the idle went normal and I also saw white smoke (steam) from the exhaust and smelled antifreeze. That lasted for about another 10 seconds and then it went away and ran fine. But I popped the hood anyway to check some things and I saw my RB header was "red hot". What could be the cause, and is my 167K+ motor 2 toes in the grave? It's an 89 NA GTU. All stock except for the exhaust (RB header, Bonez cat, and Rotary Performance catback. Only about 4K miles on the exhaust system. And, if it is dead, who can lead me in the right direction for a JDM TurboII swap that will pass cal smog?

Drivarotor

<bump> sorry guys, I just need a little insight on my problem