never heard of the track, will it be nitro too?

I'm almost certain we can get your motor to run fine on a run in bench. I think your problem is something on the car while its in motion, possibly things like fuel going through the pressure line or something, , maybe a fuel filter on the pressure line might fix it.
Lost of pressure on the tank causing you to flame out because fuel just doesn't get through the tubing. One thing about a new motor is that your fuel consumption might be totally different, what if your HSN is too lean too? There should be a few more club races after the nats before midwest series so there's still hope.

What is happening just before you flame out? Describe what your doing specifically.

Another thought could be your clutch is too tight, is it spooling out alot? This new motor might have so much power that its wearing your clutch more and its heating up the front of the engine and thats why its so hard to start after it flames out. Might just need to replace your clutch shoe. Got a centax?