I'll try and answer the questions.

How much maintainence turning that rpm?
-Valve springs every 15 runs. Rest of engine is happy for about two seasons. (45-50runs) then a good refreshing

What power levels are you getting and where do you want to be with it..??..
-The engine dyno'ed around 1450 at 8200rpm on a Dynamics modal 450DS dyno. I'm always told if it was put on a Superflow the numbers would be much different. This was detuned to this power level so the springs would last 15 runs and the rest of the engine would be happy and worry free for two seasons. The potential to push it to 1500 is there with a few quick changes.... But do I want to???

Diablo what has been the increasment in power over your t/s motor and if you dont mind me asking how much $ for a piece like this ? also did you sell both of your motors?
-Our TS engine made low 1200hp numbers. Great for what it was but the Hemi is easy 250-300hp more. There is just no comparison when looking at the stock bore-spacing engines compared to the 5 inch stuff. We sold other older styel 636 TS engine to a drag racer in Quebec and the newer 640 TS engine went to a puller is Mass. He won his club this summer with the engine and is very happy! I'll send you a PM about the dollar signs

If anyone has anything else to ask i'm happy to answer!