Hondata

So I have a few pressure transducers id like to use and a egt converter to convert the weak voltage from the egts to a 0-5 volt reading any special thing I need to do?

Yes, you need a thermocouple amplifier. It's going to be easier and cheaper to get a package with everything in it.
eg http://www.lethalperformance.com/plx-sm ... deg-c.html

I already have one sir for the thermal couplers. And what about the 0-5 volt pressure transducers I have? And the 2 ground wires I have in the little harness what do I ground them to? Also the digital inputs what can they be used for?

Have you read the info in the help file?
http://www.hondata.com/help/smanager/an ... sub=analog
http://www.hondata.com/help/smanager/di ... ub=digital