the last set i used was stamped, but the 3 before that weren't.

No stamps on mine either.

So I'm confused. Everyone who is having problems... Were you using the RA springs or OEM springs, or is it not relevant?

I just got these seals installed in my reman and will be pushing around 400 rwhp out of them. Not only did the package that they came in say explicitly to use the OEM springs with boosted engines, but it's also listed on their website. My car will use stock springs and the RA seals, and I am hoping for a long lasting healthy engine.

The most recently dissassembled used RA springs, but I have had rotor housing wear issues with RA seals with both stock springs and RA springs. In my opinion, the choice of springs does not have an impact on the engine wear problems I have experienced.

atkins are pretty nice to rotor housings...too bad they snap if you look at them wrong!

Bwahaha ^

Check the NW forum for more Atkins testimonials.

they good or bad?
i dont' have anythign against atkins...they'e very friendly people. but just about everyone i know with a turbo car (including myself) has had them go...conservative timing, afr's in hte high 10's, etc... it just kinda seems like they don't like the boosted life.

know of any n/a guys using them?

I use the Atkins seals quite a bit and I l ike them alot. We dyno'd a buddy's car that did 481 to the wheels (S4 turbo block, half-bridgeport, big turbo, race gas, lots of boost) that uses Atkins 2mm 2pc seals. They held up just fine.

B

interesting.

I don't understand what the big deal is about them. They seem to work fine. I've also spoken to Dave Atkins about them -- He told me that along time ago, when he finalized the metallic compound of the seal, he tested a single set of 6 in a boosted engine that made 394 passes at the 1/4 mi strip before tearing the motor down. His seals also are in a few alcohol-burning setups that are taking 40+psi of boost.

I think what it honestly boils down to is a lack of real tuning where most people seem to lack. There's so many things that can come into play that can eventuate themselves as a blown motor. As evidenced first-hand on Eric's car, with over 30 runs in the 400+rwhp range ultimately stopping at 481, they seem to work just fine.

Plus, if they do blow, the damage they cause is very minimal.

B

if it were just me, i'd give it up to coincidence or tuning, but this is like 10 motors from 6 guys who are all competant... and under wierd curcumstances... just getting on it to pass someone on the freeway for 5 seconds--half boost or whatever.

popped in stock or RA seals--otherwise don't change a thing and they were all fine after that except one.
but still, if you're having luck with them... i don't know..

but at least they're very nice people. i love family businesses!

who has actually broke RA seals??



I did with a hammer...but I'm talking engine related ;)

I think it was dragon or Jspecracer7 that ended up breaking one of them..
On the topic of the springs, anyone measure their springs new before installation? I had to re arc them to spec before even using them, they were pretty much flat from new, then when you install them, they dont have that metallic "ping" sound when they snap into place like the mazda springs do...
I am past the point now where my first set of Ra seals died, the engine runs ok, it is down about 5 psi from where it started, where as the other seals tend to gain 5 psi in that time.. I will be tearing down at the end of the driving season here just to have a look and to put mazda oem's back in my motor, if there is anything left of these rotorhousings and rotors..
The mazda seal is engineered with varying hardness through its entire structure which is what all the aftermarket seals are missing IMHO.. The hardening process on the seal edge gives it the wear resistance on the chrome, but probably retains some of the grain structure to retain lubricant, while the softer cast structure on the flanks gives it the softer wear characteristics on the rotor slot so it doesnt eat the slot to shit in a short time.. Some people have gone soft with the seals, some have gone hard, while mazda has incorporated both into the same seal...Max

I have. 12 psi and cutting fuel to the rear secondaries.

They held up fine for the dyno, or they held up fine over the last couple of years? I have noticed my compression has gone down just a bit over the last 6 months. And I'm running stock s4 turbo with the RA springs. both of them. And yes the Seals I used have numbers printed on both pieces of the seal.

that's a little extreme...

I was testing to see if they could be broken.
They can.

i know a dood who broke them in an n/a motor with a small streetport...go figure.

what happened?

his "mechanic" timed it by ear.

probably twisted the crank sensor around until the rpm's at idle didn't rise anymore.

not to mention the port with no fuel control... no fuel + way the hell too much timing = boom on any motor. but still...it was an n/a. you gotta fuck up pretty hard to blow that shit up. i wonder if it was a flaw in the seal(s) just on that particular motor.

i'm not the one who built the motor, so i don't know if the apex seal grooves were bad, allowing extra slop or what, so maybe it's best to not worry about it and treat it as a isolated incident.

To all the skeptics of our reports of RA apex seals destroying good housings, here are some pics from Scathcart.

https://www.oregonstate.edu/~quinnj/RA01.jpg

https://www.oregonstate.edu/~quinnj/RA02.jpg

Damn, that's worse than what they did to my S4 streetported motor which never saw above 7.8k rpm. The galling pattern is the same but I didn't have chatter that bad. I had near perfect used housings to start with too. Looks like the chrome is completely removed from the housing surface adjacent to the exhaust port. :eek:

He sent me more pics, I'll post them later. They're all twice the resolution as the ones I posted. I can zoom in on a patch of the scraping pattern and post a little closeup pic if anyone wants.

So basically by looking at the damage, the RA seals wouldn't be a good choice for an engine rebuild that's to last for several thousand miles because it isn't too friendly to the housings. Does this means that they are useless? I don't think so. As durable as these seals are, I still feel they have their place and are a great choice for someone who is purposely building a really high hp engine for street or drag.

Think about this example. Build a 500 rwhp 13b with stock Mazda seals. Driven hard I don't think anyone on this forum would expect that engine to last 40k miles knowing the stock apex seals would eventually let go. Once they let go they will do even worse damage to the housings than what's shown in the above pics. I would rather build a really high hp rotary with RA seals knowing they can take the abuse and not worry as much about blowing the engine. Also I would rather have a high hp engine gradually loss compression because of these seals than to have the stock seals fail and cause possible damage to my expensive turbo. At least those housings can be resurfaced. Does anyone understand my point? A hi hp rotary isn't going to last forever. I think these seals still have their place.

Bottom line, I say use stock seals for long term longevity and the RA seals for short term abusive situations.

i'd like to see RA seals on cermet coated housings...see how that holds up.

but again, was that the RA seals and springs, or ra seals with stock springs?

I dont think an RA motor would last 40k miles using your example, from experience I would say not only the housings would be junk in that time, but the rotors would be worn far beyond spec...The Mazda seals would last probably twice that if the tune is right, the mazda seals just dont blow out for no reason, the seals themselves are not the weak point in a tuned application, the problem is the people often tuning the setups are the weakest point... Mazda seals dont warp like the RA ones do, and dont wear the rotor slots like the RA seals either..
If the mazda seals are gonna break , under the same circumstances with a "tougher" seal, you just end up with other broken parts, just the next link in the chain effect... So the seals dont break, so you keep driving it pinging, so the rotors get dented, the bearings get flattened, the corner seals and side seals break, they score up the irons or you crack the iron at the pedestal and seize the motor solid.. are you any farther ahead? no... Fix the disease not the symptoms..
Scathcart, have you got the old RA seals from that motor, can you put them edge to edge and take a pic, I will bet there is a mile of daylight in the gap..Max

Kinda funny how this thread has resurfaced. I just blew my motor a couple of nights ago with about 6000 miles on it. I am now very curious to tear it down and see what everything looks like. I have been an advocate of these seals for a while and very happy with them. I guess we will see if that changes when I get this thing torn apart. I will be sure to post what my findings are when I do so.