What gears could these be?

[99NJCobra]

When I bought my cobra, the seller said he thought it had 3.73's but wasn't sure because the previous owner did all the work to the car. My brother in law recently drove the car and thought it might have 4.10's. In third gear at 2800rpms, the speedo says 35 but I'm actually doing 25. In 5th gear at 2500rpm's the speedo says 87 and it's actually going 65. Also, I can easily start from a stop in second gear. Any opinions would be appreciated. Oh yeah, it has 17x9 rims on it as well.
Thanks.

 

[Quadcammer]

sounds like 4.10s to me, but you need to get your speedo recal'ed.

if you want to know for sure, turn your driveshaft until your wheels turn one full rotation. Count how many rotations of the driveshaft it took.