To add to this SWAGing, I would also like to mention that Ed is not alone with his observation of excessive wear on Hurley seals.  My engine probably had 80 total hours on it before the oil cooler incident, and there's a remarkable amount of wear on the sides of my seals.  These were in new rotors, and the apex slots are still at new specs, so it wasn't caused by out of spec slots.  Leon may have a point about dust in this case, since I didn't run with a filter, and half of my running time was on the ground.  

 

At some point, I'm going to measure one of the old Hurley seals to see just how much of a groove was worn in them.  Just from looking at them, I can tell that it's much more wear than the Mazda seals in the old (??? miles) engine in the box in the garage.  Suffice to say that I'm happy that I have the new seals in my current engine.    

 

Cheers,

Rusty (firewire hard drives biting the dust left and right...)

First and foremost shouldn't everyone be reminded that Tracy's first engine had more that 800 hours before being removed for the Rensis? Everybody needs to take a deep breath and remember that. The racers really pound the seals and almost never have failures, other than obvious turbo-related detonation.

 The tolerances DO matter. The pounding on the seals from combustion is multiplied by excessive side clearance. There is no reason not to be sure our engines start with in-spec seals. I am against press forming, (which is actually called swaging), which risks crystallizing the metal. You could heat treat the material but that is more money still.

Bill Jepson