The number show that the silvia will pull on the itr low end and top end, itr is outhorsed and out torqued, numbers dont lie!!
The JDM ITR motor and red top silvia motor are different by 5 HP. I wouldnt call that "outhorsed". Pull on the top end?! Maybe you didnt see the video. Go watch again.
ITR vs. Silvia on a road track. Well honestly the silvia has the upper advantage. RWD vs. FWD. We all know fwd suffer from understeer, some ppl say the ITR is more "neutral" but then again its FWD(understeer), sure its more stable then a rwd. A comparasion that close depends all on the driver, both are good track cars.
On a road course, FWD vs RWD matters much less than in drag racing. Yes, a FWD car will normally understeer horribly, but the honda engineers did a good job by adding a stock LSD and making the rear very stiff, its so easy to make the ITR oversteer on a road course by just lifting the throttle mid turn if you wanted to.