No, the LX8 was scrapped for the UFR. The MRT6 was dropped for other reasons
Yes, it really is. It looks like an LX6 with dual exhausts and fat slicks.... If you read the thread, you would see that Victor took it out of the shop page.
I've done some memory editing with the TBO+LRF cartype, and I can say that an LX6 with a 3L I8 (can't change to V) is perfectly driveable, even on road tires. It had around 290bhp if I recall correctly.
The devs had their reasons why the LX8 and MRT6 got scrapped. The LX8 was really undrivable (way too much power with zero downforce), try to increase the LX6s power with LFSTweak to see what I mean. The MRT6 was just slower then the MRT5 because of it's downforce - and who would choose a slower, similar looking car over the faster one?
It was already mentioned: Wings weren't banned... They are just pointless weight as they mostly do autocrossing/autoslalom and don't get to speed where downforce would take effect...
It was worthless to have something that large as bbman has said, so instead they went with a diffuser under the car which has no aero effects and creates plenty of downforce.
With the Q patch tires I didn't even want to drive the LRFs at all. They were just so slidey, touchy and snappy that it made me feel bad even when I thought about the LX6. But now with the nice tires it is totally different world. LX8 would be perfect. Although I gave my own 500hp * XRT which is awesome too (just 500hp, decent sized road tires and veey big engine for the sounds ). Hint hint
I still think there are other unheard of reasons why it was never released, lets not forget how touchy the FV8 tires were back in the day (its sad to see people even today sliding that thing at the start of races).