$12,000 just in the motor....sheesh....well it's hard to beat rich people dude. If you do, they just make the car faster and come looking for 2nds, hehe.
Regardless, if his car has run a verified 118mph..and he runs you on motor only w/ your verified trap speed of 107mph..u lose...obviously so he is on crack for wanted you to run motor to motor. If you use the 150 or 175 pill, then the questions are:
(1) will you be making enough hp to be in the ballgame? I think it's safe to say that with 150shot the answer is yes
(2) will you launch/race good w/ the added power? well, i'd get in a few practice runs b4 hand....sounds like he is/was doing that already
My piece of advice w/ this race is
(1) of course, be responsible...not worth getting a ticket for bragging rights...i speak from experience here..lol
(2) if you are upping the nitrous...test it out beforehand so that you have the fuel pressure/timing set just right.......no sense in going up to a 175 shot and then finding out it's so rich that you only got like 125hp out of the deal......likewise, as others said, you don't want to win so bad that you end up leaning the motor out......if that happens and you break parts..then you end up a loser even if you do win the race...
(3) go to the track and get a number on your car w/ the 150/175 shot. it sounds like you have some time to do that now that he is outta comission for a bit....
BTW, let me just say that $12,000 for a motor....well...if I ever pay that much...it'll put me into the 10s @ 125-130mph.....just the motor.....