Assuming you'll be racing him at the track...just race him and find out. If he's being a pain, just take him out and shut him up. The guy sounds like a moron for talking crap about V6 Mustangs. I mean is the V6 Mustang the performance bar or something?
You shouldn't have a problem with him. You should have him off the line, and be able to hold the lead. But if you wanna really take care of him, get some gears.
Also, 175hp is a bit of a stretch for your mods.