Have a read of this page (
http://astronomy.tools/calculators/ccd_suitability) and use the calculator at the end. Plug in your scope and camera, with / without the reducer and see the results.
If you do that, you'll see that you're probably going to be oversampling with the ASI1600, which is not ideal.
If you had a 0.67 reducer and it worked for focus, etc, then the ASI1600 would be fine.