What I was telling you guys was stuff I could barely remember, just rough figures. He's in the 14's and dipping into the 13.9's. I've personally talked to jimmy over the phone several times about the irtb setup. Currently he's pushing even more power since he's just installed a 99-00 bp engine, in the mag he still had the 1st gen bp engine which makes less power to begin with and his car was chosen and done for the feature more than 4 months before the mag came out so a lot of tuning after that was done. In addition to the instantaneous throttle response and better airflow the reason why he's able to pull off those times with that hp figure is because the car weighs so little and the gearing is very short. The idea of irtb's isn't about significant power gains.
Here's the link to a timeslip showing a 14.1 1/4 run with 130whp(which would be about 170 at the fly) on stock internals with the new engine
http://www.fuji-racing.com/fujiracing_046.htm
Now thats with the stock 9:1 compression and stock cams, imagine if he upped the compression and used aggressive cams he may be able to make mid-high 13's! 1/4 times are pretty irrelavent to how this car is gonna be used but he uses it as a benchmark to show people how fast the car can be since telling someone who doesn't understand the advantage of irtb's isn't going to be woo'd by the low hp figures.
If you're serious about getting irtb's he will work with you on pretty much any japanese inline engine, the kits he shows are what he has readily available off the shelf. He never had an s2k irtb kit, but if you goto the site you'll see an s2k project car because he was willing to work with the guy in putting together one. In your situation it'll be much pricier since you have an inline6, thats 2 more tb's needed. Fuji-racing isn't the only shop doing these setups though, they just happen to be creating a big buzz with the miata community since the owner of the shop is a championship time attack and auto-x'r
I talked about this stuff a while ago on this thread btw