Breifly. I went to one of our RR days at Northampton Motorsport last year and went in what can only be described as a missile of a vx220. There's a world of difference between a RWD car and a FWD. The vx acceleration was difficult to put into words but all I can say was that I couldn't move my head off the seat as it was pinned back.
I've spent a lot of cash on my car over the years with mixed feelings. I can't justify spending anymore on engine mods. I'm happy as it is now.
The initial conversion was just over £6k. I'd already spent around £3k on the previous head work, Schrick cams ect. To go onto Stage 3 i'd be looking at another exhaust system which would be over £1k front to back. The rods and pistons fitted over £1k. Uprated injectors, the list goes on.
As a home build you can cut the cost consideribly. Time would be more of an issue though.