Mr. Lamar,
Our engines came from Daryl Drummond, who builds all of the engines for the Formula Mazda series. Those are street ported 13Bs at 160 HP. Some of those people run them for 2 years between overhauls. Our bridgeported 12A he wants back after 8 hours. We had two of them and both lost rotor bearings. 

[Makes sense. Rotor bearings and rotor weight limit RPM's]

One a front, the other a rear. Both were running within temp and RPMs when they
failed. The peterson pump keeps them above 90 PSI. Mr. Drummond had sent us an Email
warning us about mazda shopping around bearing suppliers and had a dose of bad race
bearings. 

The engine we have left is the cast iron from no 1 and one housing each from one and
two. The crank and rotors are mine. The Drumond rotors were lightened with the long
chambers. mine are old small chamber but with the old one piece race bearings. The
corner seal springs are flat C shapes I had not seen before. [Those are the 1993 and
up 13B corner seal springs]

Max power (245)is at 9450 RPM,. We have 9500 chips in the MSDs. 

[That is a rev limiter chip I take it]

The first engine complete with 5 1/4" dual disc Tilton clutch and starter ring was about $14,000 ready to run. The second was a long block, dynoed with his intake and carb for $5,000. It was worth it. once I got a good exhaust header hooked to it, we are 3-4 seconds a lap faster everywhere we go. We plan to run this engine a very long time before Daryl gets to see (whats left) it again. 

His ports were not much bigger than I was doing. I couldn't find any magic inside to
point to as the reason his run so good. When I build our backup motor this winter I
will copy his ports. My last engine came out of the car after 4 years of racing. Aol
dumped this off my screen. Sorry......LEH


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