My tack readings are as follows, keep in mind I have a tuned pipe I picked up second hand so I,m unsure of the brand?

Fuel used is my own mix of 10% nitro, 10% cool power synthetic oil, 10% caster oil and 70 % methanol.

11x8 APC- 13000 rpm
10x8 APC- 15500 rpm

These are the only props I've Tacked. I've used 12x7 and 13x6, the 13x6 seemed to unload too much in the air with the prop going supersonic. The 12x7 was very good however took a few secs to come on pipe.

The 10x8 was still on pipe at half throttle in the air and really got my World Models 46 size Miss America moving. The 11x8 was great too though the vertical was not quite as awesome as the 10x8 however the level speed was very similar to the 10x8 just without the rpm.

When I get more readings I'll post them.

Adrian.