Hi Paul,


I just talked with Sven again.

It seems several points of my information were incorrect.  Sorry about this.
Sven feels, as I do that, it needs to be corrected.  Here goes. I put the
corrections in CAPITALS.


I called Sven Nielsen up a few hours ago and spoke with him for 45mins.
He is no slouch and is quite knowledgeable about seals and coatings. This of
course is the opinion of someone who isn't:)  But I know human nature and
when he realized you weren't going to bite him he opened up and shared a lot
of information.

Yes he does have the seal edges radiused and no he doesn't have glass fiber
in the ceramics.  He did say that there are many many types of Silicon
Nitride out there and the maker he has located has provide a product he
feels is superior to Iannetti.

THE POINT ABOUT SUPERIORITY HAD TO DO WITH THE POINT ABOUT HOW THE TWO PIECE
SEALS WERE DESIGNED AS MENTIONED IN THE FOLLOWING SENTENACES NOT ABOUT THE
TYPE OF SILICON NITRIDE USED..

Sven mentioned on his two piece design he> copied Mazda older seals used on
the rotary trucks because it was more appropriate for use with ceramics.
Basically that design as you know has the long piece stretching all of the
way across the rotor housing and the tip is ground flat.  The wedge part
rides underneath. He explained in detail too long to write about why this
method is superior to Iannetti's seals.  Basically ceramics don't like sharp
points.

Ceramics are lighter than iron so spring pressure had to be increased and
his spring surfaces have been ceramic coated to make the wear characteristics
closer to the seals.

He has developed  several other proprietary chrome as well as ceramic
coating techniques as well. On the RX-7 discussion groups he is known as
GlassMan.

He invented the Cermet process and is aquainted with Ron at Pineapple
Racing.

NOPE CERMET HAS BECOME A GENERIC NAME AND THE PROCESS WAS INVENTED BY J.H.P.

HIS NAME IS ROB AND HE IS A CUSTOMER OF NRS CERAMIC SEALS.

Supposedly Ron ROB coated the housing too thick once and instead of
bringing the housings back to him to redo, the owner went somewhere else and
ground the coating down to paper thickness.  This resulted in flaking.

NOPE, IT WASN'T HIS SHOP THAT DID THE COATING.

Another point is that Sven applies the coatings using a compression
technique while Ron was using a technique putting the coating in
tension.?????

AGAIN NOTHING TO DO WITH ROB.

No details on this topic except a coating under tension tends to widen any
developing cracks.

ACTUALLY  COATINGS WRONGLY APPLIED TEND TO PROPGATE AND FORM CRACKS.

Puerto Ricans are running 40psi boost with his seals and they are holding
up under detonation events.  Side housing seal clearances are set according
to amount of boost.

THE CUSTOMER HAS TO SET THIS CLEARANCE THOUGH.


One interesting piece of info.  In Aussieland

ACTUALLY IN NORTH AMERICA

an one (1) rotor engine was
putting out 300hp on tremendous boost and detonating constantly.

IT WAS BECAUSE OF A WIRING MISTAKE BUT BECAUSE THE SEALS WERE FREE FOR
TESTING THE RACER DECIDED TO CONTINUE TO TORTURE THEM TO SEE HOW TOUGH THEY
WERE.

One sealdid crack in the middle but the engine continued to be used.   In
his opinion side wall clearance is very important and the lack of clearance
is usually what causes  seals to disintegrate.

He said at a group buy we could purchase a set of his Grey seals for around
$955.

He has heard of different techniques for installing P-ports like screwing
them in, pressing them in, gluing them in and even TIG welding them in.

He said and Mazdatrix confirmed that the Renesis rotors installed in a 13B
would be fine except for the side seals.  They are too sloppy in clearance.
As much as 0.002"

ACTUALLY MUCH MUCH HIGER CLEARANCE. OVER 0.016 IN SOME CASES.

We discussed the possibility of ceramic coating them to
build them up a little and this was my suggestion and reflects zero
knowledge on if that is even a good idea.  To his credit he did say "I don't
know" to several of my questions,  or "You will have to test it"

He thinks the one or two piece 3mm seal would be fine for the Renesis
rotors.

He has been in business 7 years and all sales have been by word of mouth.
Recently a production bottleneck of radiusing the seals sharp edges by hand
has been overcome by a local company being able to do the job with a new
machine allowing 150

ACTUALLY 250

seals to be radiused in one night.


He has no sales into Japan that he knows about as yet although Aussies are a
big market.  About aftermarket seals he agrees with you. There is a lot of
crap out there.  Some seals from Aussie turn into bananas quickly. He wasn't
surprised when I mentioned about the chatter marks on Dave Leonard's engine.

I told him that because of your experience with so many people buying
inferior 2nd party seals you were quite leery about people claiming that had
a good product.   I said that basically you were a nice guy who gets grumpy
sometimes when he doesn't have enough bran in his diet.  HA HA!  Just
kidding .... about the bran:)


AGAIN SORRY FOR THE MISTAKES.  I EXPECT SINCE SVEN IS RECEIVING THESE POSTS
NOW HE WILL JUMP IN COMMENT ON HIS PRODUCTS DIRECTLY

DougFir

Don't coat rotors with ceramic or anything else for that matter.
The benefits if any are not worth the risk.
If it does come off the rotor housings are history in short order.
I have seen this happen with my own eyes.

Paul Lamar

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