Just found a video of the exact kind of vehicle you're talking about. Take a look/listen from 2 minute on. Also take a look at the similar videos on the side:
The Antique Engine library might have the source material you need: http://rabbitearsaudio.com/rea009-antique-engines/
Or if you want to record/design it yourself, you may be able to work with small propeller plans, steam engines - maybe a sewing machine in there? I'm thinking with the train or plane I'd you'd want to EQ out a lot of the rone elements of the engine and emphasise the more mechanical, chugging elements.
You mention the vehicle in your cartoon is powerful - so maybe a steam train would be a good base there. Give it a bit more oomf - but without making it sound like a modern car and emphasise the steam power aspect. Though if you want some off-time car engine sounds, my housemates' 1980s sedan has a kind of a chugging rhythm to it. Depending on how much material you need I could record some of that for you.