Some clasic american V8 (Ford Mustang, Dodge Charger,...)
RB4 is good. Its looks like Supra with 4*4 from Impreza but slower. I like 4 door sedans with 4*4 (impreza, lancer,..) 0-100kph 4.5sec, 250kph, 2.0 turbo.
Or stronger (cup) version of RB4. This can looks like this: Wide and powerful.
Race trucks - This can be interesting racing. They have limited top speed (150kph) and very fast acceleration.
Truck like team buggyra can be very interesting.
Buggyra:
Can pressing shift up + shift down buttons together in sequential mode shift gears to neutral like in real cars? This can be usefull when you crash. This wil be fastre then 5-4-3-2-1. Thats all what i need.
It is very easy to build. Sliding sleeve is only rust-resistant steel with screw and few female screws. Inside i only remove one spring and wires to buttons (May be i make small control panel :-) ) .
Software? http://forum.rscnet.org/showthread.php?t=232514
Everthink what you need to build you can see on photos.
Take rubber, piece of steel and try it. I was improving sliding sleeve for few hours. Now looks like this. It's Little faster.
I like games realy realistic so i bult my own H-shift.
This is a result of my modification.
1) I remove parts what were useless. Front/back spring, flying lever and i fix joy to chair.
2) I use pipe 9mm i to original plastic axis. I must to do reduction for shifting ball from screw. Ball is screw thread M12 (12mm). On pipe is short screw thread M8 (8mm)
3) Next step was creating shifter sliding sleeve from 1mm rust-resistant steel.
4) Little color synchonization with my Driving Force PRO. Belt is handmade from skin.