Did some more testing and performance improvements this past week.
Clutch: Changed in some custom parts and springs. Peak hp changed from 40.63 to 42.43. But that's not the big news. From 20mph on up it had a good 3-5hp gain and it didn't stop until just over 56mph. This is a great mod!
Exhaust: Didn't alter it yet, but did run it with and without the endcap. With the endcap tops is 42.43hp, without the end cap it maxes at 44.59hp. It's particularly effective at low rpm, but shows improvement across the whole range up to 40mph where it is about the same with the cap, but then shows improvement again all the way to max speed of 56mph. I'll work on getting a muffler made that will take advantage of the lost hp.
Overall it's looking good. Had the head flow tested and it looks like it's a well designed head that will flow a lot of air, more so than the Raptor. We should see some very significant gains from the top end. I'm shooting for 60hp to the wheels, this puts it in 900s range. We might even make it into 900XP range. With the increase in power, I will most likely move to larger tires, like 30". This will increase my top end to where it needs to be.
More updates in a few weeks after the next WORCS race and maybe even news on the a-arms!