Looking good man. Since you're on a budget, I'll give you a couple of cheap ideas to gain you a little more power, at least in the gears you'll be using for autoX.
1. 2nd gen direct fire ignition mod. Very simple and easy to install, great increase in driveability and throttle response. Slight hp increase. Cost as low as 20 bucks
2. Add an Efan. I like the 1st gen MR2 fans (dual) because they mount up very easily, can usually be found cheap (I got mine for 20 bucks), and will free up a bit of power and torque in 1st/2nd gears.
Also, I just wanted to add, I always did just fine with the stock seats. The trick is to pull the seat belt very tight, then stomp the brakes to lock it in that position. I usually do this as I'm pulling up to the start. Do it right and it will hold you tightly in place.
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