I'm looking for the best combination of gears to really get some good low end punch for a technical track, but some good top speed in the straightaway as well... I have the 13,14,15 clutch bells, and 44,46t for spurs....The buggy is an Xray XB8 with Vspec motor

13/48 is what you need.

I like the 48 better than a 46. You'll get a lot more useful gearing options with a 48. Anything above 13/46 is just too high unless the track is huge.

Using the stock kit spur and clutch bell is the best setup for the track you describe, the trick here is to turn the clutch shoes around for a more positive bite when you hit the gas.

Also play around with different length headers.

Shorter for torque, longer for top end speed.

Even tyres make a huge difference on acceleration.

A short header and top end pipe with a super low gearing can be better than a low end pipe with a long header and high gearing for a short track.
The reason? When you move the power band up in rpm the useful rpm range usually also gets a bit wider.

Just get a Jammin JP-5 pipe and be done with it.