It is my experience that the SE-R takes 87 Grade fuel, and the Spec V takes 91. This is one of the major reasons the spec catches 10 theoretical horsepower more than the se-r. Other reasons are supposibly specially tuned exhaust (although part numbers are the same) and different intake. I'd bet the only difference may be a more aggressive intake and a ecu mapped for the 91 octane fuel. That should be enough for 10 ponies, and makes sense.
Either way, never give the dealer a reason to turn you around and get his foot stuck in your colon. Don't volenteer info, and if asked, know the right answer and give it. I complained of a smell from the Vent, oil usage, and engine noise, and they said "that's normal". Now there's a recall for just these issues due to some goofy thing with the precatalyst.
They will take the easy way out, so by all means don't give them a door is what I'm saying. You should use the fuel recommended though for you're own sake and the sake of your sanity.
Your friend played a game, and will prob lose, unless he fibs about the gas octane he uses.
I have the SER and use 87 99% of the time, no probs. Edmunds.com used to list the octane numbers and that was one of the reasons I stayed away from the Spec V, with gas prices as they are.
BTW, my info is for 2002 models only, I have no idea if Nissan has had the desire to change this since then. Good luck and have fun!
Jey
