NRS Ceramic Apex Seals (1-Piece, OEM Height)
02-13-2011, 09:56 AM
#176
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02-13-2011, 10:40 AM
#177
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and at high rpm, arent the seals already under pretty significant centripital force - how much added spring pressure can you really implement in an effective manner?
I realize these arent questions that have simple easy answers you can just spit out. just thinking out loud. and again i'm only thinking of the use we see of seals among these types of communities, ie the 99% of ppl thing
I realize these arent questions that have simple easy answers you can just spit out. just thinking out loud. and again i'm only thinking of the use we see of seals among these types of communities, ie the 99% of ppl thing
Remember the starting mass is a lot less with ceramics 1/3 approx so centrifical force is a lot less at the same rpm.
How much added pressure can be implemented effectively? Lots, more than double on a heavy spring set. Probably triple on the wimpy stock springs.
Phil Liard built an N/A 13B with 2mm 1pc seals, at the time I did not have a 2mm spring kit. We took the stock 2mm springs and cut an outer to fit the inner slot, then hard faced them. We even put a tighter arc to them and heat treated afterwards. Phil noticed that at high rpm (9000+) there was feedback through the intake proving the seals were lifting at high rpm. Once he installed the heavier spring kit this went away.
I talk to a lot of builders in what I do and I don't think ceramics are a waste for these engines, from what I understand you breath too hard on the factory 8 seals and they bend. Every N/A rennie should have ceramics. They don't flick with the same mass so the grooves do not take a beating. Driven hard at 25,000 miles on oem and the tips are flared badly.
02-15-2011, 04:41 PM
#179
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Probably around 4 - 6 weeks, maybe less. I don't have any sets coming on my stock order due to no one asking about them. I only make them on request at the moment. That will change once I get enough demand and people realise we offer them.
02-17-2011, 12:06 AM
#183
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My friend, I've reduced the cost of them substantially since introduced to the market 11 yrs ago. Iannetti seals are twice my PREVIOUS prices. It really doesn't get better than this........ everyday excellent value 
Well....there is one time it gets better than this;
Once every Christmas NRS has them on sale at insanely low prices so everyone can afford them
So I guess then it does get better than this....only at Christmas time though.
Well....there is one time it gets better than this;
Once every Christmas NRS has them on sale at insanely low prices so everyone can afford them
So I guess then it does get better than this....only at Christmas time though.
Last edited by glassman; 02-17-2011 at 10:56 AM.
02-17-2011, 07:25 AM
#185
Would you mind explaining the difference (pro/cons) to using your one piece verses your two piece? If it is goal or build dependant can you elaborate on that as well? I'm looking to pick up a spare motor and having a set of your ceramics put in but I would like to know which set would be best for me. Thanks in advance!
02-17-2011, 10:33 AM
#186
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Sure, basically we recommend you go 1pc if boost is over 20psi but 1pc can also be used in any build. 2pc will seal better and offer about 4% better sealing plus a torque gain. We've found the NRS 1pc seal about as good or a bit better than OEM 2pc seal. This is mainly due to the added spring pressure.
The dynamics on the 1pc is quite different as the seal floats between the plates and does not make contact.
The dynamics on the 1pc is quite different as the seal floats between the plates and does not make contact.
02-17-2011, 11:22 PM
#187
Cool, how about the difference between stock height and FD height, would you recommend a mill to FD height or is that also build dependant.
20psi... are you talking about a non renny here and if so how does that correlate to the higher compression renny?
20psi... are you talking about a non renny here and if so how does that correlate to the higher compression renny?
02-18-2011, 12:00 AM
#188
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Yes we are talking non renny.
There is still varying opinions on taller seals in 8 rotors.
Benefit; you get a taller seal that is stronger and has more seal meat in a taller groove which gives it more support when flicking thus less groove wear. But ceramics are light and kind to the grooves to begin with so how does this translate to the short seal
we simply don't have enough data yet. But definitely better than steel for groove life, this is proven.
Down side; heel of seal and spring area exposed to exhaust and thus carbon deposits. What does this do over a long period remains to be seen then shared within the community.
There is still varying opinions on taller seals in 8 rotors.
Benefit; you get a taller seal that is stronger and has more seal meat in a taller groove which gives it more support when flicking thus less groove wear. But ceramics are light and kind to the grooves to begin with so how does this translate to the short seal
we simply don't have enough data yet. But definitely better than steel for groove life, this is proven. Down side; heel of seal and spring area exposed to exhaust and thus carbon deposits. What does this do over a long period
remains to be seen then shared within the community.
02-18-2011, 01:28 PM
#191
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Good info, so if I would run a pheripheral port rotor housing (can be in or exh, or both) with rx8 rotors, would it be a wise decision to keep stock rx8 height ceramic seals? or better to machine the grooves and go for FD height seals?
02-18-2011, 04:53 PM
#192
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If you're going PP intake and side exhaust with 8 rotors the tall seal will have exhaust exposed to the underside of the seal and springs. The short seal for me would scare me on either PP intake/exhaust but who knows it might be fine.
If you go PP intake and exhaust with 8 rotors then the tall seal is the best option.
If you go PP intake and exhaust with 8 rotors then the tall seal is the best option.
02-18-2011, 06:38 PM
#193
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Last edited by zoom44; 02-18-2011 at 06:52 PM.
02-22-2011, 07:24 AM
#194
My one piece only lost about 1" of vacuum (it was seal or porting, since I did them at the same time) - but crank to start is still fine, even in bitter winter cold. After the engine sitting for a YEAR, hooked up battery, 4 turn and it fired right up and settled into a nice idle.... so I don't think 1 piece are that big of a daily driver compromise to make.
That being said, the ONLY reason I went FD height, is cause they were not offered in RX8 height at the time.
That being said, the ONLY reason I went FD height, is cause they were not offered in RX8 height at the time.
03-02-2011, 05:50 PM
#195
you will be much better off on the taller seals in the long run, the shorter seals are known for not lasting as long as the FD seal modification, even on an NA app (this is from a well established world class pro builder), plus look at it this way
if you have two fence posts and you bury one two feet in the ground and the other four feet in the ground, both protruding the same amount above the ground, then you pull/push both of them back and forth with equal force which one will be more likely to wallow out a hole around where it protrudes from the ground and become lose first? The shorter one ....
if I had the option I would choose to use the deeper seal regardless of the cost to do so
if you have two fence posts and you bury one two feet in the ground and the other four feet in the ground, both protruding the same amount above the ground, then you pull/push both of them back and forth with equal force which one will be more likely to wallow out a hole around where it protrudes from the ground and become lose first? The shorter one ....
if I had the option I would choose to use the deeper seal regardless of the cost to do so
03-02-2011, 06:15 PM
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you will be much better off on the taller seals in the long run, the shorter seals are known for not lasting as long as the FD seal modification, even on an NA app (this is from a well established world class pro builder), plus look at it this way
if you have two fence posts and you bury one two feet in the ground and the other four feet in the ground, both protruding the same amount above the ground, then you pull/push both of them back and forth with equal force which one will be more likely to wallow out a hole around where it protrudes from the ground and become lose first? The shorter one ....
if I had the option I would choose to use the deeper seal regardless of the cost to do so
if you have two fence posts and you bury one two feet in the ground and the other four feet in the ground, both protruding the same amount above the ground, then you pull/push both of them back and forth with equal force which one will be more likely to wallow out a hole around where it protrudes from the ground and become lose first? The shorter one ....
if I had the option I would choose to use the deeper seal regardless of the cost to do so
03-02-2011, 06:19 PM
#197
if you have two fence posts and you bury one two feet in the ground and the other four feet in the ground, both protruding the same amount above the ground, then you pull/push both of them back and forth with equal force which one will be more likely to wallow out a hole around where it protrudes from the ground and become lose first? The shorter one ....
Then again - if you bury one 8ft into the ground you wont be any better off than the 4ft one (depending on a few factors of course) .....
