Looking at a E70, guys says it's 4.8is?

[electricalserv x5]

I have been thinking about picking up a E70 , it is in great condition, with a sets of winter wheels ,BUT the guy wants $21.5k it has 105k miles ,the going rate for that car with those miles is $18k.
But the guy says it's a 4.8is E70 , now 'is' BMW cars have upgraded suspension,sway bars , a sport tuned engine and I believe shorter stroke then a [E70]4.8i .
I checked and I think BMW didn't even make a 4.8is E70.
it goes...
4.4 305bhp
4.8 350bhp
4.4 TT 400bhp
4.4 TT 540bhp.

any heads up would be appreciated.