Joeys build isn't about a lag wagon top end screamer. If it makes peak power at say 6500 and comes back 20 kw or so at 8000 rpm that would pretty much nail it.
There is soooo much left in this setup IMO
E85, more boost (22 psi WTF?!?!), it would be a different kettle of fish!
Petrol cars run like a hairy billy goat compared to a full E85 tune. It's bloody night and day!