I see the usual suspects got the car (Ultima - the car Top Gear wont let around the track) and yes the plenum is on backwards with a plate as jeff pointed out.
The fuel rails are also backwards - someone should have spotted that - Jeff
For its compact size an LS series engine may have made more sense. If going down the modding road then it sure would save a lot of money for any gains made but its been done loads of times over in these cars. The LT5 makes it somewhat unique, looks a whole lot better and I'm sure its the best sounding Ultima on the road
The guy did tell me what the car weighed but I dammed if I can find the figures from memory it was about 2/3 of the weight of the Z so certainly not slow