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Hey Chris,
The V8 killa video is too long for my photobucket account (max 5 min).
Can you post a link to the video? I kinda want all the vid's on this page.
Hey Chris,
The V8 killa video is too long for my photobucket account (max 5 min).
Can you post a link to the video? I kinda want all the vid's on this page.
An NRS Ceramic Power Seals customer in Australia built a 20B using the 3mm 1 pc grey seals. The purpose was to grenade the engine to see what it would take. They were unable to do so.
Here is a message from the builder:
"Pete update, 700lt meth used now !
762ftlb@7600rpm
1196@8500rpm
Power peaks @ 9700rpm
these power/torque figures on 29 psi"
The builder claims the seals have far better durability than any other product thus far.
Two turbo’s gave up the goat during testing.
Prior to testing the builder stated that he could grenade any engine in 125 – 150 litres of Methanol. I am happy to report that this is no longer the case.
After the first 500 litres of Methanol they "officially" completed over 30 full power passes.
Testing was also done at 38 psi and in the builders words "Engine STILL running sweet".
Here is a bit more info on La Sarita. At Pan Am they ran a 7.45 and did a compression test after that run. The car at this point had run over 30 passes and the compression was a perfect 120 psi all around.
The engine did break at about 35 pssses but this was due to the throttle body closing 2 plates in the run. They fixed the throttle body, put in a new engine and they are running fast again with no problems.
Quality, relialability and consistancy is what it's all about. That's what you can expect from NRS Ceramic Power Seals.
I would like to take this opportunity to give credit where credit is due.
A special thanks goes out to Jeff McCall from Rotary Power in Gardena California.
Jeff played a crucial and pivotal role in the design and development of NRS Ceramic Power Seals.
Jeff, you are to be commended for your knowledge and insight of the rotary engine. Thank you so much for everything. It's because of your unselfish offering of your knowledge that NRS was able to get it right the first time. Hat's off to a true rotary superman!
NOW! if you were manufacturing an engine and it had a well known fault, why would you not ,even if it cost did extra money, not try to correct the problem. just to show the world you can manufacture a better engine, especially if the engine has reached CULT status in the world ! maybe this is just to logical. well! maybe Mazda engineers are CULTISTS themselves! DARN never thought of that till now! You have to admit that Mazda rotarys are a little unusual in the world of transportation, but i understand that they have some DIESEL rotarys runnin around, and they also have some experimental HYDROGEN rotarys on line. what kind of APEXs would they put in those engines were money was not an issue, for R&D. just tossin insome logical thought here. RON
I think you're missing the point, the stock apex seals aren't at all a fault for stock or even decently modded engines. some people even make 600rwhp with stock 2mm seals! also, stock apex seals have lasted well over 200k miles in a properly maintained engines. mazda has no reason to spend the extra money for these seals, which even if mass produced would be way more expensive. ceramic is just more expensive than steel, and also the different tools required to machine ceramic correctly are not going to be as cheap as what it takes to machine steel. also, mazda already makes steel, has everything set up to make steel, and switching would be a big commitment.
with that said, i dont mean to take anything away from the ceramic seals, they're absolutely amazing, the best aftermarket internal rotary upgrade ever invented as far as im concerned. they can handle huge power, crazy boost, and crazy RPM's without missing a beat. its just not worth mazda's extra money to put them in stock engines.
I would like more data on how ceramic seals work in conjunction with cermet coated rotor housings?
I would especially love to know what the compression is like after a significant amount of running time/wear.
What I would be woried about would be the interaction of cermet and ceramic seals in the long run. It seams like the combo of ceramic apex seals + cermet rotor housings and good tuning would make for the most stout longest lasting rotary engine ever.
But I want more data on how ceramic seals work in conjunction with cermet coated rotor housings?
I would especially love to know what the compression is like after a significant amount of running time/wear.
I'm sure a lot of people would like more data, truth is the cermet has not been readily available long enough to give you the LONG term data you are after. Perhaps Marc will jump in and tell you what he has seen. He has purchased many sets of NRS ceramic seals for use with the cermet housings. I believe Mazda noted almost immeasurable wear on the 787B engine, seals and housings alike.
If you are looking for the best wear option against cermet then ceramic seals are what you want.
Quote:
Originally Posted by slo
It seams like the combo of ceramic apex seals + cermet rotor housings and good tuning would make for the most stout longest lasting rotary engine ever.
I really didn't think it was possible to come up with a better material than the NRS grey seals but that's exactly what we did.
If you thought the NRS grey seals were the best there is, I would have agreed......until now. NRS grey seals have proven themselves time and time again in some of the most demanding applications. Why?? Because we chose what we believe to be the best and toughest materail available anywhere. Well we've done exactly that again.
We believe this new material is better than anything anywhere PERIOD.
I am not going to get into a massive amount of spec's on this new material but I will tell you about it's fracture toughness. Our current material set's itself apart from others of its kind with a fracture toughness of 8.0 MPa. Typical materials of this kind have a fracture toughness of 4.0 - 6.0 MPa and the current materials fracture toughness of 8.0 MPa is what has made it so successful.
Are you ready for this? The new material will have a fracture toughness of over 10 MPa, actually approaching 11 MPa!! This we feel is bar NONE.
Do NOT be fooled by cheap immitations. Since NRS released the grey seals others have tried to give you an el-cheapo version of ceramic seals mimicking the NRS Black seals and riding on the coat tails of our hard work.
I'm sure there will be more of these el-cheapo ceramic seals offered in the future but do not be fooled by an attractive price. If it's cheap to buy, it's cheap in quality. You get what you pay for simple as that.
Please do not hammer me with a thousand questions about this new material, I will not respond.
I thought it would be good to have some details on customer cars using NRS Ceramic Power Seals in road race applications.
James Elsworthy of BRM Technology in
Victoria, Australia
Here are some details on Cameron VandenDungens car:
Rx7 ser2 Improved production
13B J-Bridgeport
NRS Ceramic Power Seals - 2mm 1 pc
Wolf3d EMS
2x 55mm IDA T.B. with trumpet injectors
Guru flywheel
Powertrain Technology 7.25" twin plate clutch
Guru 5 speed dog-box ser5 case 1:1 5th
Guru Torsen L.s.d
Yokohama 195/60/14 A048
Koni Ext. adjust all round
Guru Panhard rod
Custom full floater rear end 200sx callipers ser Rx7 discs
Saab front disc ser4 callipers
AIM MXL dash logger
Wb02 Lambda logger
This is what James had to say about NRS Ceramic Power Seals:
"Over 200 rear wheel kW, sees 10000 rpm regularly, regular front runner. VERY impressed with product - couple of hard seasons - even at 14000 rpm one day. On that occasion, the NRS Seals lasted, eccentric and ring gear did not......"
"Seals show no wear, and a marked reduction in apex seal groove wear."
I had that in mind also. But I didn't explain the question properly.
The apex seal grooves in the rotors, will the NRS 3mm seals fit in place of standard mazda 3mm seals?
I read at some time that the mazda ceramic apex seals would not fit into standard 3mm rotor grooves. Example, if you wanted to use them in pre 85 cars that came with 3mm seals, machining of the rotor would be required. I'm asking this because I allready have a set of rotors that where milled to 3mm by atkins.
Thanks..
Yes the NRS 3mm seals will fit in place of the standard Mazda 3mm seals that came with pre 85 engines with no rotor machining required. In fact all 3mm grooves from the factory are the same thickness dimension 13B or 12A. Regardless you will always need to measure your seal to groove clearance no matter what seals or rotors you use, whether it's a factory slot or milled/wire cut to 3mm.
Pics of New Micro Finished NRS Ceramic Power Seals
Here's some recent pics of the seals.
These have been done in our NEW micro finishing process. The finishing process by far makes the NRS Ceramic Power Seals the best they have ever been.
Perfectly de-burred and radiused edges are completely seamless and even on all edges. Microscopic peaks have been swept away as the finishing cleans up the parts all over.
Better oil retention, strength and sealing are the results as the process slightly etches, sweeps away stress risers and gives a more uniform surface.
Your no longer chamfering the 3mm down to a 2mm edge anymore? Also, will this new surface treatment extend the life of the springs (assuming the new surface process is done under the seal where the springs ride)?
Your no longer chamfering the 3mm down to a 2mm edge anymore? Also, will this new surface treatment extend the life of the springs (assuming the new surface process is done under the seal where the springs ride)?
~Mike...............
Hi Mike,
The chamfer to 2mm is optional. But you are correct as for now we are not producing the chamfer type. What was noticed is that small carbon deposits were collecting on the chamfer area which as you know we don't want this to happen. What we will try at some point is a blend to the radius and use the tighter 2mm radius for a better blend thus removing any flat "pocket" for carbon to hold onto. I wouldn't expect this to happen any time soon as there are way too many other developments happening right now to start on this.
Yes the botttom is done too but I don't think the micro finishing will offer better wear on the stock springs. One of the first things I tried after the springs wore so quickly was to polish the bottom of the seals to a mirror. This did not decrease the wear much at all, the springs wore out as fast they just polished like a mirror as well. It may however have a positive affect on the hard faced springs as they will be micro finished too once we're set up. Time will tell.
2007 promises to be a very exciting year for NRS as we will be testing several new ideas and never before tried potential products. Of course updates will be posted when the results are available
I have been using these seals for 2000 miles now. They perform as advertised. They have already saved me one rebuild due to detonation from bad gas. Whew, mony well spent. Thanks Sven.
John
I have been using these seals for 2000 miles now. They perform as advertised. They have already saved me one rebuild due to detonation from bad gas. Whew, mony well spent. Thanks Sven.
John
Thanks for your kind words John. I'm happy that you're happy.
Regards, Sven
Yes the botttom is done too but I don't think the micro finishing will offer better wear on the stock springs. One of the first things I tried after the springs wore so quickly was to polish the bottom of the seals to a mirror. This did not decrease the wear much at all, the springs wore out as fast they just polished like a mirror as well. It may however have a positive affect on the hard faced springs as they will be micro finished too once we're set up. Time will tell.
Is it not feasable to have a thin metal plate on the bottom of the ceramic seal for the spring to ride against? No wear on plate to seal as it is static and you can tailor the plate for good wear characteristic w/ spring.
I'm not sure exactly what you envision but I had thought of an isosceles trapezoid placed into a slot in the bottom of the seal in the four places. When you consider the additional grinding costs plus the weakening of the seal it did not seem feesable or practical.
I think the hard faced springs are the easiest fix and they work great too. The only additional grinding is the depth of the spring cuts on the seals is increased.
After reading all 15 pages, next year when I build my motor, NRS ceramic will be the way to go. One question, what's the main differences between 1 peice and 2 peice?
The difference between 1 & 2 pc seals is mainly low rpm sealing. Cranking compression will be higher but not much gain will be noticed at high rpm. 2 pc seals are favored in N/A engines as they offer a bit of a torque increase. 1 pc seals are favored in turbo engines as they are the strongest version available.
One of my customers in AU recorded the highest cranking compression ever in 3mm with the NRS 2 pc seals. I believe it was in the 130 - 140 psi range.
They now use NRS 1 pc seals because in Scott Flemmings IPRA circuit racer they have smashed every record last year and have been the most dominant ever in the history of the series.
I will be gathering more info from Issy at Select Maz soon along with more details, pics and video of Scott Flemmings car if available.
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