either use badboy's BootStrap calculator ( he recently posted a new updated link to it in the Help & training section )
or use Spatula's Aces High II Aircraft Comparision Tool, which is currently version 2.0 I believe.......
it is similar to Badboy's except only shows no flaps or full flaps.. I think spatula uses Kweassa & Mosq's old speed data though....only newer models since those original data numbers were gathered have more updated info/data....
Badboy's is based on Excel Spread sheet with formulas pre-inserted..... you MUST READ the pdf guide that goes with it to understand how to fully use it..... ( if you don't have Microsoft Excel, you can get OpenOffice for free , it will also work with Badboy's spreadsheet...... )
Spatula's Performace Tool utilizes Microsoft's .NET Framework, so you need to have all your .NET patches installed on your MS OS...... if you don't mind using the .NET stuff.....
hope this helps.....