OK I posted about this earlier and it seems not too many people are using these seals yet.



I was told by a very prominent shop here in Tokyo told me that Mazda 2pc seals were yokunai or not very good. He explained how he has cars that he tuned and were running fine just like always then they blow. In Japan your options for Apex seals are not that numerous, suprisingly, so unless you put NB seals for 2000dollars you pretty much have to use Mazda stuff. I also notice that any shop that has a serious race car like Pan Speed, Amemiya, Rmagic and KSP they all use NB seals in those cars.



Anyway I bought mazda 2pc seals and put them in my engine and it broke in nicely and pulled good vacuum and ran very smooth. I started off keeping the boost low and stuff as ususal. With this engine I am using a TDO6H-20G and the motor is ported. For fuel I am using 720's in the primary and 800's in the secondary with stock regulator and GT-R fuel pump wired constant 12v. After breakin I ran the car at .8k of boost and using a wideband the AFR seemed to be about 13.5. At this point I was using 550/720 injectors. Later I got the 800s and went to the 720/800 setup. After installing the injectors I went to the Power FC and richened all the cells from .6k of boost all the way to the max. While driving and tuning I noticed some knock on the sensor and using the test page pulled 3deg out and the knock went away. This led to redoing my entire timing map and pulling timing in various places. I never seen a knock number over 26 while driving for 2 weeks.

Another session with the wideband showed and AFR of 11-11.5 Much better and the car felt strong and knock was low. I was happy with my car and was going to put it on the dyno and log the AFR and look at the tourque curve and so on to do more tuning............... Well last saturday we went to Touge for some drift and there was many cars there .........to be the dipshit showoff rotary guy I am I cracked the wastegate in the tunnel and pulled through third deafning everyone.....LOL went to the end turned around and came back in the same fashion but about 6grandRPM from best I can tell it broke...leaving me with a lot less power and a lumpy Idle. No drift for the that night.

The seal broke in two places as you can see from the picture but most of it was intact. one corner apparantly went out the exhaust and the rotor housings were fine and the rotor only has one scratch on it.



Does anyone else have experiences with these seals or advice on this situation? I am going to be building a FD soon and am thinking of using Rotary Aviation seals or Atkins but I want to determine the root of my problem before I start blaming the seals....

the stock seals are deffinately known for beign strong. stronger then atkisn and i think RA. it seems your tuning was still quastinable. i woudlnt run 11.5 with anything more then 10 psi or 250 at wheels thats still kinda lean or not comfortign enouf i shoudl say. what timing were u runnig anyway, knock sensor can only detect so much, so i woudltn go by just that. it also depends what condition teh rotor apex seal grove is in, the top piece of the stock seal is not very deep so its not too hard to knock it out with some detonation.

11.5 lean? I've always been told to tune for about there under boost. what do you tune to kahren?

NB seals?





-Ted

NB seals means No Break..... I don't know who manufactures them, It could be Scoot. Scoot used them in the Wangan 710hp FD. they cost 1300 dollars for set and the NB corner seals are about 95dollars for a set.



This is way out of everyones price range so nobody uses them on the street.



As far as my delima we pulled the motor and replaced the one seal and put the motor back in. I finished it all up today and it runs fine I have added even more fuel from row 15 down.



Timing from P16 and N10 it is all below 15deg. I did find that my fuel filter was a little dirty and I replaced it with a new one. Blowing through the filters there is quite a difference in how easy it is to blow through the new one.........If that even matters I am not sure.

This sounds really fimiliar. I am running the same seals in my 90 TII motor and it did something very similar. The motor had about 5 thousand miles on it, was tuned for 11.5 to 1 AFR with 4 720cc injectors, and was running 14.3 psi of boost on a BNR stage 3 turbo. Now mind you the night it blew was very cold(25 degrees or less) and the air was very dense. I decided like you to show off my car. I took a friend out for a highway run and hit about 6500 rpm in 4th gear and felt a slight hesitation. I let off and shifted to 5th and things seemed fine until I got off the highway and came to a stop. I had a lumpy idle and was pulling a bouncey 4 inches in vacuum. I took the car to Gotham Racing for tear down and possibly a warranty repair. Well it's not going to be warrantied. The seal cracked and spit out a piece. It scarred the housing it broke in, nicked my turbine blade(still good for use), scratched one rotor face, and went into the other housing and scarred it up also. Now I need 2 new housing, new seals, possibly one rotor, and all new gaskets and orings. I'm going to go with the rotary aviation seals and springs and the Atkins solid cornmes seals and third gen springs. I'm also going to go witha lot of other things to improve the reliability of my motor that should make it last a very long time, I hope. Based on this experience I can't really say weather the seals suck or not. You're the first person I've heard say something bad about these seals.

BTW the seals I'll be using are supposed to be way stronger than the stock seals and only cost $184.00 plus shipping. I think overseas shipping is $30.00. Their website is www.rotaryaviation.com, check them out. They have a good write up on the seals in thier FAQ section.

you should have them get more aggressive with the temp correction maps, dont want that to happen again

yeah i cant run more than like 10-12degrees or timing witout some audible pinging either.

Yeah I'll ask Steve to do that. BTW just so everyone knows Gotham Racing didn't do the tuning on my car. I opted to have Rotary Performance do the tuning. Hopefully Steve's tuning works out way baetter than RP's. Iv'e seen some of Steve's tuning and I'm very impressed by what he do with stand slone system.