burping has nothing to do with tuning frequency.
Do you have a wall? That box diagram above looks like a CRX or hatch back box.
A wall in a maxima will be quite some distance from the dash. Tuning may be around 55hz. But the best way to tell is trial and error. You build the enclosure, then play a moderate volume sweep and use a termlab to tell you peak frequency. Then play that frequency at full volume and record your SPL.
Then shrink the airspace of the wall and do it all again.
If you dont have a wall and your sub is in the back, tuning will be much lower.
The 2500 series is good, but not meant for 2500w. I see a blown coil in the future.