I just bought a V6 93 Dakota 2WD and my exhaust carbonizes my garage wall when I start it. Any Ideas how I can cut down or eliminate my exhaust spew. Also any quick ways to give my 250K motor a little pep without killing it?  

if your V-6 has 250,000 miles on it, you already answered your question about why it covers the garage. Probably, the only fix for your V-6's issues is a rebuild at this point. As far as adding "pep", again, a rebuild.