1. Go to CIH north america home page.
2. Look in the bottom left corner, should be 3 items each with an arrow that you can click on
3. click on "Compare Specs"
4. Click on "harvesting equipment"
5. click on "Axial Flows"
6. click on model you want or if you have a somewhat older model click on "archived models.
Deere and Company have the same sort of comparison charts on their website. I'd imagine some of the other manufacturers do as well. Not sure if there are any free sites that offer such services, hesston. Some googling time might turn up something. Hotline Equipment Guide is a great source for specs, years produced, location of serial numbers, etc. (they even show the MSRP from the final year of production for various models) Also, Iron Solutions and Iron Guides offer some good specs on combines (moreso in terms of pricing according to model year, options, etc.). These publications and real time online services cost, but they provide some great information. Hope this helps.