I would like to know if you can give your armor piece a turpentine wash over your acrylic paint job? Would I have to seal to acrylic paint with a clear dull coat and if so what brand of clear dull coat should I use?

IAm no expert but i just done it yesterday without sealing and didnt seem to affect the acrlyics. But if its a really important project i would wait for a second opinoin

As long as the acrylics have been given ample time to cure you should not have any problems. By ample, I think of a week or more.

Hey thank you Ken.

First give a pair of coats of Future applied with a soft brush. Then the oil wash. I do that with my models and it works fine

I usually do only selective washes or better "highlighting". Anyway I don't do it directly on matt surfaces because they thend to absorbe too much of the colour and not only wher I want it to be. So either if the underlying coat of paint is acrylic or enamel I always give it a coat of clear gloss (usually acrylic) before going on with my selective wash.
On top pf that consider that a wash with a dark colour over a model usually darkens the vehicle surface...
Ciao

I laways use acrylics as the base coat, and have never had a problem using white-spirit thinned oils over them, just so long as the acrylic is fully dry.