Time for an update!
I ordered a RIPS RB30 bottom end with some extra goodies inside plus a high capacity sump. RB30's require an extra oil gallery for the VCT if you're putting the RB25 head on, but rather than do that I've been a man about it and I am converting the head to solid lifter which gives me more cam choices. This means the baby Tomei cams I bought at the start of the year and never got around to using are being sold and I've ordered some Tomei Procams (270deg 10.25mm), solid lifters and Tomei valve springs rated at 9500rpm.
I was going to have the head ported and put some bigger valves in but it really isn't necessary for what I want the car to do, plus I think I've already spent enough money on it this year!
500hp at the tyres is my goal and I know it will achieve it, however a lot of people are telling me that the 35/40 won't hold up at 500hp for long. I don't believe them, but if they're right then my plan is to use a Borg Warner S366 or S400. Guys in the States are making good 1/4 times on BW turbos in Supras so they seem to be pretty good and a heck of a lot cheaper than a GT42R or something like that.
More updates to come when the bottom end turns up from NZ!