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First, I made the suggestion to the comp board to allow the ceramic seals. The reasons are quite simple. 90% of the engines that come in for service are due to loss of power. That loss of power is generally caused by apex seal related issues, warpage, leading edge wear, or seal groove wear. In the last three years, where we have been attempting to hold a 2.5 hp power band on the engines fresh leaving here, these issues have become more evident, particularly the apex seal groove wear. With the reseal testing we have seen the large majority of engines tested 3-7hp off what I would call the minimum fresh engine. In most cases the power loss is directly related to apex seal and or groove wear. That is not to mention the competitor who slightly over heats the engine, doesn't kill it, but it's down on power, warped apex seals. The same applies to the guy who tries to go too lean, or too much timing, or gets a load of bad gas and the power doesn't come back. Or, the seals that just wear a little faster, or warp because they can. This is all the stuff I see and would like to see it go away.

As far as performance, the testing done has been on two seperate occasions, with two engines in both sequences of test, different engines in the two different test sequences. The parts tested were stock N304-11-300, IAS two piece seals, and IAS one piece seals. The engines were freshened with the stock seal and tested. The engines were then disassembled and reassembled with the one piece seal and tested, then the two piece seal and tested. The test results were a significant loss of power with the one piece seal, 1.5-3hp to the stock piece and a similar power to stock with the two piece ceramic. The results were consistant in two test sequences. So what about all the claims of performance advantage to the ceramics. The two piece IAS seal is all most a direct copy of the stock Mazda seal, the IAS requires more spring pressure. When new, the sealing surfaces on both types of seals are straight and flat, so that the compression sealing function should be and is similar. The reason the IAS seal requires more spring pressure I believe is the lighter weight does not allow as much centrifical force against the rotor housing to aid in sealing. The bottom line, is that in our back to back testing, with new seals, there has not proven to be a performance advantage. The other issue is apex seal groove wear. This is an issue because it takes very little wear for the compression gases to leak around the apex seal and into the next chamber contaminating the incoming mixture which causes a definate power loss. The IAS seals greatly reduce this wear as evidenced on the GT engines we build in the shop.

So why would I, who stands to make more money on the frequent engine rebuilds, suggest something to cut down the frequency of rebuilds. Simply this, when I see a situation that can be improved, I would like to take care of it. Understand, the time the engine runs, probably won't increase, but for the time the engine runs, the hp should remain more consistant. The other thing is I have yet to replace an IAS seal in one of our much higher performance engines because it has worn out, or replace an engine rotor because the seal groove is wearing.

Why the IAS seal. The maker of the IAS seal, Francesco Ianetti is a materials engineer with a specialty in ceramics. His seals have been run in competition since the early 90's with excellent results. He has great quality control and inspection processes. They do what we need them to do in the class and are a proven product.

The part would be offered as an alternative to the stock part and when new offers no performance advantage. The decision to use them would be up to the individual. If it saves one overhaul, even just an apex seal replacement, they have more than paid for themselves.

As for the new pro car, they will be delivered with stock steel seals. An upgrade will be allowed to the ceramics. The ceramic seals for that configuration are currently being made. If you have any questions, please feel free to call or e-mail me, 707.445.3786 fastrotary@earthlink.net.

To answer your question Larry, I am recomending the IAS 2 piece seal as it duplicates the hp of the stock seal, the one piece does not. The cost is about $2200 per set at this time. FYI, I purchase these through Mazda with very little mark up. The reason for the cost over a one piece is virtually two pieces are being made to very high tolorences from high quality custom material. The real issue is the labor to make, finish, and inspect two parts.

In regards to the low hp Renesis engine, to my knowlege no one is working on this engine as there are none available. I am receiving some parts in cooperation with Mazda Competition department to build one from parts, but not all parts are available yet.