Email me at: NRS Rotorsports@shaw.ca
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NRS Rotorsports |
Ceramic Apex Seals |
Lead | |
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I heard ceramic seals are being allowed in the Formula Mazda cars in 2004. Would anyone like some information on the Ceramic Apex Seals that NRS Rotorsports offers?
Email me at: NRS Rotorsports@shaw.ca |
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glenn cooper |
seals | ||
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Call me a cynic, but I'da sworn this was a B.S. posting. Except for the facts that it's right there in black and white in the new issue of Sportscar. Whodathought?
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Max at FCE |
seals | ||
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Coop, I didn't know it either, and the dealers are supposed to be kept in the loop. I told the guy who started this page that those seals were only for the new car!!! Boy, was I wrong.
Max |
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Max at FCE |
seals | ||
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Coop, finally I've got the straight story about ceramic seals. By the way, isn't this thread in the wrong place? Mayby Jim wants to move us somewhere else.
The ceramic seals are just proposed by the Comp Board - it's not a done deal. Personally I don't feel like they are necessary. Why? The seals add about $2,000 to the cost of parts for a rebuild on a 13B. They are NOT a performance advantage. They only extend the lifespan of the engine (supposedly). So your engine rebuild goes up from around $4,500 to $6,500. For a few dollars more you can get Hasselgren to rebuild an FA engine. This seems a little silly for an FM club car. Also, the guys at Star Mazda did not know that the Comp Board was considering this. It's not something Star Mazda was in favor of because it raises the cost of running your car. It sounds to me like they will be an option. Pesonally I don't think they should be allowed at all because of the unnecessary expense. If any of you feel the same way, write or email both the Comp Board and the Board of Directors at SCCA and tell them. Believe it or not, they DO listen!!! Max Stauffer Formula Cars East www.FormulaCarsEast.com |
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NRS Rotorsports |
ceramic seals | ||
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As far as I know Ianetti 2 piece seals run about 2150.00 a set. NRS Rotorsports premium 2 piece seals run 1895.00 at full retail and the alternate material offered in a 2 piece run 1495.00 at full retail. Either type will work great in a N/A engine. I am not sure I agree that they offer no performance advantage, seeing that they are half the weight and torque gains have been seen. Really what it comes down to is reliability and performance. A set of ceramic seals could and have survived in 5 different engines. When you look at it from this perspective, you may never have to purchase apex seals for your engine again. The savings on that end justify the potential one time cost of ceramics. As far as prices go, NRS Rotorsports is very willing to negotiate a substantial discount to the builder based on quantity for the series. This could bring the racers price down considerably.
Happy Trails, Sven Nielsen NRS Rotorsports nrsrotorsports@shaw.ca |
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ferris11 |
seals | ||
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I don't understand why anyone would want this upgrade?
If we all run the same equipment, we're all equal. By adding this performance item, is a significant cost to anyone who wants to compete. People will feel obligated to have the engine rebuilt with the new seals simply because it is a performance advantage. I think it's an unnecessary idea that just increases the cost of running the cars. The engines last a long time as it is before a rebuild. Jonathan Beeler |
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JimFMRacer |
Re: seals | ||
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This topic discussion has been moved to the Rules section for further input.
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LarryWinkelman |
Ceramic seals and new engines | ||
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One other thing to be considered... VMC has proposed a version of the Renesis engine, de-tuned to about 190 hp, for club racing. So, after you've spent the extra money on your 13B with ceramic seals, which will last *forever*, your motor is going to be obsolete in a couple years (if the VMC proposal comes to fruition). Perhaps we ought to resolve the former issue before allowing the latter.
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Ken Erb Velocity Motorsports |
Re: Ceramic seals and new engines | ||
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I believe the suggestion of allowing the new Renesis motor is for several reasons namely the fact that our present 13B motors will be increasingly hard to come by. I might be wrong but I thought that the Renesis motors already have the ceramic apex seals.
Ken |
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ferris11 |
seals | ||
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I don't think the issue is really ceramic seals, or not:
If everyone is using the same parts, then we're all equal. If there isn't a problem with the current configuration (and there isn't) then why change? If we were getting a significant enhancement, either performance or reliability, I could understand it, but this doesn't seem significant exdept in the dollars department. If the new engine uses ceramic seals, so be it. But I don't think that there's a reason to change the old engine at this point, especially if it looks like it's being phased out. JB |
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Daryl |
ceramic apex seals | ||
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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. |
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LarryWinkelman |
Thanks | ||
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Thanks for the explanation. To clarify, though... are you recommending the 2-piece IAS ceramic or the 1-piece? Is it really $2000 additional?
Also, are you working on the club version, 190 hp, Renesis? |
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Daryl |
ceramic seals | ||
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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. |
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JimFMRacer |
Re: ceramic seals | ||
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Dear Comp Board
Can we please get this issue resolved before (not after) I have to send my motor in for re-sealing before next race season begins? Thanks |
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ferris11 |
daryl | ||
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ok. Well, from the well described reasons that Daryl explained, it has almost convinced me to agree with him. Especially since Daryl is undoubtedly the authority on this subject.
However, for the amount that I race (rare due to finances) an additional 2000 isn't in my future plans, especially since our engine has about 3 or 4 races on it, total (and it runs great, thanks Daryl). I'll save it for next rebuild, though. Hey, Daryl, what kind of time (hours) on an engine were you seeing when the apex seals caused the engine to lose compression? This way we can decide when it might be time for a rebuild with the new ceramic seals. |
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Daryl |
apex seals | ||
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We have seen the apex seals have problems in just a few races. I think there are contributing factors however. Running lean, running too much timing, etc., are the major contributors. If one runs on the conservative side in those regards, there are generally minimal problems.
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JimFMRacer |
Re: apex seals | ||
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Daryl,
How well do the ceramic seals work on used/old engines as opposed to brand new motors? I have spoken with a friend who runs an RX7 in ITS and he thought that there might be issues without proper machining and even then it might be best to use new rotor housings. |
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Daryl |
ceramic apex seal | ||
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Jim, I use only rotor housings that are new or like new condition, even with the stock seals. The issue is chatter wear on the minor axis of the surface of the housing and that is considered unusable. So that would be a non issue in this case.
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glenn cooper |
ceramic... | ||
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Hi Daryl, Thanks for the input. I was wondering about the apex seal springs themselves. Are they the same part # on ceramic as steel? It seems to me that they are the cause of a percentage of low or no compression conditions. If I'm correct, due to several factors (overheating, detonation, normal wear and tear) that the little leaf spring behind the apex seal will give up the ghost so to speak, loose temper and or colapse. So even if the ceramic seal is so much better, actually longer lasting is probably more appropriate, it's really up to the spring to ensure this. Comments?
BTW: Thanks, that fresh engine I got before the season started has done real well, Top 10 in 7 of 9 Pro races this year, resulting in a season ending 9th in series. |
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Daryl |
ceramic apex seals | ||
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Glenn, you are correct on both counts, they are the stock apex seal springs modified on the ceramic seal application and they have been a cause of problem in the pro serries. For use with the ceramic seals, two springs are used, both shorter than the stock part, but made from that part. This gives the higher spring pressure needed by the ceramics to seal, see my 1st post. The problems with the springs has been evidenced in the pro serries, but not seen in club, is the springs loosing tension due to a unique detonation situation which causes the seal to pulsate up and down fatiguing the spring. The way to avoid this was to be conservative with timing. I do believe, with the ceramics, the higher spring pressure would work to off set some of this problem. Not to say the ceramics are the save all deal, but they would definetly minimize the issues we are seeing in club racing.
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ferris11 |
Re: ceramic apex seals | ||
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far from being an expert in this area, but if I heard that the springs/seals could take more abuse, wouldn't that encourage us to lean out the engine and increase the advance, even more?
Hell, if the seals/springs can take it, wouldn't we try to get that much more out of it, possibly causing the same problems? |
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