[TitaniumTT]

Originally Posted by glenrx7

Nothing over 8k, here is the deal my man. It being harder is the issue. If you have a hardened piece of metal you need to temper it in order for it to be able to have "memory" with out memory it will bend and stay that way. Tempering will soften it in comparison to a non tempered hardened shaft.

Shaft deformation is something that is natural and will happen.[/quote]

I wonder if the tempering is the reason why the 8 shaft is so much cheaper than the 7 shaft.

Do you remember what the clearances were on the main bearings? Could it be possible that some slop in the mains allowed the shaft to flex?

Originally Posted by glenrx7

Look, I dont want to brag or try and make my self look great or anything like that I try and stay humble, to help you out let me give you a little background info.

I was trained to build the top racing rotary engines by Paul Yaw of Yawpower. I built all the engines that came out of his shop for the last 6years or so. Paul moved on to motec and injectors so no more engines, He helped Tom and I start azrotaryrockets.

We are also "sponsored" if you will by Mazda, i act as tech support for there rotary team and motor sports team.....

After coming from Yaw Mazda came with us, they send us project and customers, so I would say we know a little about this subject.

So take my word or dont ...I was aiming to help thats all....Good luck.

I appreciate the help. It's rare to get someone on the internet with actual knowledge and experience as opposed to spreading lore and rumors. Honestly, thanks for the advice.

Originally Posted by glenrx7

Ok, well some of your logic is flawed. The rx8 is an na engine with a low combustion pressure putting less stress on the shaft. You increase combustion pressure and you increase forces on the shaft. So for the sake of argument lets jump into black and white for a second. Combustion pressure basically aquates to torque, if you increase it the tourque will increase increasing the force aplied to the rotor, bearing and shaft. So with boost you increase combustion pressure. So with out the turbo you have less force on the shaft even at 9k.......Not to mention the torque on a renisis is well we all know that ./

Yeah, pretty much my thoughts exactely. The combustion pressures and the torque produced by a turbo-charged rotary are going to be far greater than the torque and chamber pressures places on an N/A engine regardless of how high it spins

Originally Posted by glenrx7

Let me also say that i am not sure what torque rate you would have to exceed to bend this shaft but I know 300+ and you are going to be in trouble I doubt chadwick is anywhere near that..


I hope this all does not sound defensive I am about as articulate as a 3 year old on acid that lots there mommy....That s why I do not teach.

I didn't take it as defensive at all, so no worries.

I would suspect Chadwick is right around there. I should be abour 300 RWT and keeping it under 8k for sure. We'll see what happens I guess. I have a friend making ~450 RWT with that shaft and hasn't had any problems so