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-   -   Precision Ceramics apex seals? anyone tried em? (https://www.rx7club.com/single-turbo-rx-7s-23/precision-ceramics-apex-seals-anyone-tried-em-1079474/)

rx7jocke 03-02-15 12:19 PM

Precision Ceramics apex seals? anyone tried em?
 
In my hunt for 2mm 2pc ceramic apex seals i came across these

Ceramic Apex & Tip Seals - Precision Ceramics

What are your thoughts about em? Nrs is not avalible anymore it seems and ianetti is both rare and very expansive (2x nrs)

7krayziboi 03-02-15 07:04 PM

My opinion...
I spoke to someone who drift FD's locally (where NRS is established) and actually tried them in one of his car
And told me not to go with them...told me to go with Goopy
I trust him cause his a famous builder/racer around here
Being the lawyer of the devil I personally tried to find the Shop to have a look at what his shop would look like , cause to sell "super seals" like that the guy must have a decent shop ,I spend 2hours going around a corner trying to locate an address that I think doesn't exist...
Anyways...just be careful what you buy and go with something people actually tried and had success with it

t-von 03-02-15 10:09 PM


Originally Posted by 7krayziboi (Post 11878712)
My opinion...
I spoke to someone who drift FD's locally (where NRS is established) and actually tried them in one of his car
And told me not to go with them...told me to go with Goopy
I trust him cause his a famous builder/racer around here
Being the lawyer of the devil I personally tried to find the Shop to have a look at what his shop would look like , cause to sell "super seals" like that the guy must have a decent shop ,I spend 2hours going around a corner trying to locate an address that I think doesn't exist...
Anyways...just be careful what you buy and go with something people actually tried and had success with it

Remember this is the NA section so was the drifter boosted or NA? Ceramics have always been a poor choice for boosted applications (including NRS).

7krayziboi 03-02-15 10:46 PM

Well I think think of it.... I've only seen him drift on boosted application , I didn't ask him if he actually used them on N/A application.When I asked about what seals to used,it was related to my boosted matter.

rx7jocke 03-02-15 11:11 PM

This is the boosted section....and afaik ceramics work for boosted aplications aswell...especially a low boost 20b (500hp)

7krayziboi 03-02-15 11:14 PM

I failed to see it was the N/A section..sorry about that

He called me a few weeks ago to see if I was interested in his seals. I remember he gave me a good price compared to what others sells his seals.
I still have his phone number, maybe I can try to hook you up if that's the direction you want to go.

All I wanted to say is that In the list of
-Canadian Rotary Shop
Listed in this forum , his shop has an address.

Sooo I tried finding the address (GPS & google map & iPhone map ) that lead me to a dead-point In town (Edmonton)

Maybe I should of just asked him personally when I spoke to him few weeks ago where/what happen to his shop.

Anyways I'm not trying to downgrade his product
That was just my experience.

t-von 03-03-15 08:53 AM


Originally Posted by rx7jocke (Post 11878830)
This is the boosted section....and afaik ceramics work for boosted aplications aswell...especially a low boost 20b (500hp)



Your right about the thread section...my bad! Ceramics have been a poor choice for most highly boosted 13b applications because they destroy everything when you blow the engine. There perfect for NA applications IMO. There's a ton of history on this forum to support that. Now a 20b at a lower boost is something else but still I wouldn't trust them on a boosted rotary. I would rather install RA seals that are proven not to destroy turbos when they let go. Plus you gotta do something pretty stupid to break one.

Rub20B 03-05-15 09:55 AM

Been Running the NRS 2mm 2 piece now for 1 season of circuit racing in 13B PP. even with a lot of problems with the carb running the engine really lean at 9k5 rpm (11.5 ngk plugs with cracked porcelain) the seals are still perfect. if you clean them one could not identify them from new ones and see they have ran over 10 hours between 7 and 10k rpm. after one race the exhaust was from manifold to muffler tip white as paper from the inside, seals didnt mind.

Now I got an email from Rice racing saying all good about his new steel seals. price is quite steep about the same as ianettis (~1900 usd) but someone will have to give them a try to see what they're worth in a boosted apllication. For NA I would dare to say ceramics are king..

t-von 03-05-15 03:39 PM


Originally Posted by Rub20B (Post 11880024)
Been Running the NRS 2mm 2 piece now for 1 season of circuit racing in 13B PP. even with a lot of problems with the carb running the engine really lean at 9k5 rpm (11.5 ngk plugs with cracked porcelain) the seals are still perfect. if you clean them one could not identify them from new ones and see they have ran over 10 hours between 7 and 10k rpm. after one race the exhaust was from manifold to muffler tip white as paper from the inside, seals didnt mind.

Now I got an email from Rice racing saying all good about his new steel seals. price is quite steep about the same as ianettis (~1900 usd) but someone will have to give them a try to see what they're worth in a boosted apllication. For NA I would dare to say ceramics are king..

I want the NRS for my NA 20b.

7krayziboi 03-07-15 11:17 AM

It's good to hear that someone is having good Racing Result ,
I'm curious on how much Mileage a NA 13B/20B could get on the street with them (in the world of a good build engine & tuned properly)

In other words... Is the price difference gives extra miles ?

Rub20B 03-07-15 03:52 PM

I think as long as you dont detonate them hardly (will never happen in NA apllcation) they live forever. in this season what they stood through.. previous engine had steel seals and they took out rotors and housings in one season (3mm hurley crap seals altough) running 10000 rpm less.

t-von 03-09-15 12:31 PM


Originally Posted by Rub20B (Post 11881244)
I think as long as you dont detonate them hardly (will never happen in NA apllcation) they live forever. in this season what they stood through.. previous engine had steel seals and they took out rotors and housings in one season (3mm hurley crap seals altough) running 10000 rpm less.


And this is exaclty the reason Mazda should be putting these in stock NA engines. Why they don't....I have no idea.

t-von 03-09-15 12:37 PM

It wont let me edit my above post. Rub why did you go with steel 3mm in a hi rpm NA? I've never heard of housings lasting at all with steel 3mm for long durations while racing. Notmal street car is something else.

Rub20B 03-09-15 03:45 PM

Car had this engine inside and it was built by some rotary specialist in the UK good up to 8k5 occasionaly 9k we had ben told (me was thinking 2mm steel or carbon seals, but didnt pull the intake to check). so we drove it til 8k5 on track and the last 30 min race of the last race weekend we had to finish one rotor. still won in our category but the engine was totally gone, rotors, housings, bearings..

it had some strange 3mm steel seals with really wide tip piece. the height of big parts of the seals was worn till less than a rx8 seal. also rototing assembly would have been balanced it was told. in reality on rotor was drilled randomly and grinded on both sides (I think in an attempt to lighen it) but was still more than 50g off as compared to the other rotor.. anyway only reused side housings and E shaft =)

rx7 SE 03-24-15 08:15 AM


Originally Posted by Rub20B (Post 11880024)
Been Running the NRS 2mm 2 piece now for 1 season of circuit racing in 13B PP. even with a lot of problems with the carb running the engine really lean at 9k5 rpm (11.5 ngk plugs with cracked porcelain) the seals are still perfect. if you clean them one could not identify them from new ones and see they have ran over 10 hours between 7 and 10k rpm. after one race the exhaust was from manifold to muffler tip white as paper from the inside, seals didnt mind.

Now I got an email from Rice racing saying all good about his new steel seals. price is quite steep about the same as ianettis (~1900 usd) but someone will have to give them a try to see what they're worth in a boosted apllication. For NA I would dare to say ceramics are king..

Had an 'interesting' chat with Peter as well about his new seals. Anyone have any results from them?

bumpstart 03-24-15 10:19 AM

"interesting"

or just deranged ?

for years peter has libeled other makers of steal seals , particular kev from SCR ( same as PTS and power seals )
he also managed to shitcan several motors using ceramics,, all while he promo'd them as unbreakable too , and he changed his tune ( litterally ) and blamed them too

here is my view on the matter -
peter has no metallurgical background
from some reports the new seals are the same stuff .. at a premium price
and AFAIK not one person has posted any housing pics , or reported any meaningful KMs
the only relevant skill peter has here is the talk. and the ability to produce a CAD diagram

my 2c is to stay well away.. snake oil

haltechguy 03-25-15 04:54 AM

I agree with bumpstart - stay well away from rice racing steel seals, at least until 20 or more people can vouch for them. He tried to sell them to someone I know, saying they have all the properties of a ceramic seal except they cant be broken (they have the ceramic seal price tag to go with them too - $2200 per set of 6!). If he thinks they can match a ceramic in all aspects he is deluded. The main reason a ceramic performs so well is because it is light weight, and is not affected by heat. Something a metallic apex seal will never be.

Apparently there are many people running his seals (including the worlds top drag racers), he just cant give any examples because everyone made him sign non-disclosure statements. Totally believable.

As far as steel seals go ALS / E&J seem to be the best all round seal. They are generally nice to rotor housings and make good power.

chibikougan 04-10-15 12:14 AM

Hmmm

peejay 04-10-15 05:24 AM

Apex seals run hotter than the rotor for the same reason that piston rings run hotter than the piston. They see a lot of sliding friction.

t-von 04-10-15 01:10 PM


Originally Posted by 427 Doubletree (Post 11898710)
the ceramic does not grow at all at any temperature? they say on site, dis can be the only reason my bud had wid hot start issue that totaly went away with stock seal in it looks like big problem for daily dat needs to stop start when hot he had to change dem because problem was to bad to live with


Were the ceramics not 2-piece?

chibikougan 04-10-15 02:04 PM


Originally Posted by 427 Doubletree (Post 11898710)
the ceramic does not grow at all at any temperature? they say on site, dis can be the only reason my bud had wid hot start issue that totaly went away with stock seal in it looks like big problem for daily dat needs to stop start when hot he had to change dem because problem was to bad to live with

Them stating their ceramics do not grow at all is hooey. They will grow just less than Aluminium Filled Carbon Seals do.

BLUE TII 04-10-15 02:08 PM


this makes no sense at al cause the engine will heat up and grow since its made from iron and alloy and the ceramic from their own words will not grow so this means they will then leak as the engine warms up? a buddy of mine with one piece ceramic seals had exactly this problem that the engine was hard to start hot makes sense now when you read on their own quote that ceramics doont grow? my but got so frustrated with the hot start problems took out ceramic did not find issue no bend or funy weaar stick in mazda and the problem went away maybee for racing car when its always going and not hot starting they ok? but in road it was bad to push start car all the time when engine warm up gud luks like the problem is this they no grow at all and leak to much compresson?


Silicon Nitride Properties

Coefficient of Thermal Expansion

10–6/°C (10–6/°F) 3.3 Metric (1.8 standard)

The ceramic seals have a lower coefficient of thermal expansion which is desirable because the seals have a higher working temperature than the rotor housing (cooled by coolant) and the rotor (cooled by oil). As stated the seals see the same thermal loading as the other engine internals, but does not have its own cooling PLUS the added frictional thermal loading which sends the temps through the roof with high RPM.

A steel (Coefficient of Thermal Expansion almost 4x higher than Si3N4) 1 piece seal would have to have such high end clearance cold to avoid seizing hot it would not start cold.

One piece seals will always seal worse than 2 piece seals as they have to work with cold rotor housing width (short) and hot rotor housing width (longer).

Additionally, the manufacturer makes the 1 piece ceramic seals on the short side as you have to machine the rotor housing width down to match the seal length because the ceramic seals are not easy to machine.

Also, the manufacturer has to account for noobs that will put the 1 piece seals in an engine without properly measuring the rotor housings/clearancing.

If the 1 piece ceramic seal motor was properly clearanced and still hard to hot start I suggest putting in a very high power ignition system which will get it started with the lower hot compression and have the added benefit of more high rpm power/ ability to tune rich AFRs with no loss of power. Plug life will suffer.

Or of course switching to 2 piece ceramics if that is an option.

Note- properly clearanced and operating the thermal expansion from friction will give the engine good running compression/sealing on 1 piece seals. The frictional thermal expansion just isn't in the seal yet on a hot restart.


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