The sentimental car....I can see that being a reality, for sure. Can't sell the second car, just bought it. Plus it was the first car I ever drag raced and I couldn't pass up the opportunity!
Cool calm heads now but if the crash happens heads wont be so calm. Depending on how it happened it could very easily turn out what you thought what was a "very knowledgeable drag racer." just became the " imbecile" in less than 7.50 . Not every wreck is so easily conclusively agreed on. Everyone outside has their single personal opinion and the driver has his.
Like others have said partnerships are tough. Tempers and disagreements happen all the time without them. Personally I wouldn't do it. But if you want to take the risk, and it is all your risk, for a very small monetary gain go for it. For everyone around you sake I hope your a extremely cool tempered fella. :-D