"Here is a 400mm in igs you can easily modify and work with if you want"
Not sure that is forcing you to do anything, was just trying to help get the thrust up. Now I know that your only concern is price and not thrust I totally understand what you’re not trying to achieve.
Yes the others are very expensive yet they are at the top end of what is possible with those inlet diameters. I talked of costs in relation to Vasyfan vs. turbines in the same class (50 kg + ), yours was not included in that comparison.
Your comment regarding kit cars is mute as there are numerous "kit cars" that cost far less than a Mercedes E class (???) that have truly monster performance. 572 crate at 700hp can turn anything into a beast and not break the bank.
Regards,