Converter stall speed recommendations

You have 3.91 gears and you want to keep it economical? BTW: when describing what you want for a converter saying it's a "warm 318 duster" means absolutely nothing. You need specs and lots of them. A converter is probably the most important part of the drivetrain and you can't just guess what "warm 318" means. Get on a converter manufacturers website and download their converter spec form and fill in all the lines. If you don't you could end up with a converter that it completely wrong for your combination