teknics

Well they said that they were built for the airplane engines, and those engines dont see the kind of heat that the turbo rotaries produce. Im sure you read the whole thing on the club tho, i figured everyone did.



kevin.

FikseRxSeven

hey brian, how long ago did you first use RA springs and seals for your customers? any of them getting ready to be taken back apart?

1Revvin7

I believe it was JspecRacer who measured his RA apex seal springs after 10k kilometers and found they had lost some of their spring height or something to that affect...

DrifterRX

See I sent an email to them with this question and got a we don't know what you'r talking about reply, and theres no information anywhere on thier site about this either.

Dragon

Out of 7 or 8 engines ( I forget ) that I've build between when the RA seals first came out - 8 months ago. only one has blown and that was recently. It was in the car for about a year and a half-2 years and was built with some of their first batchs and with new rotor housings. The owner of the car ran it lean a lot after he made some intercooler pipe changes and other mods. He then didn't retune after several warnings from me and finaly blew it. Even then it was a top end run with some good pinging from what he described and all it did was make the idle stumble. He hasn't brought the car down to me yet, but I'll probably be tearing it down in the next couple weeks to rebuild it. I'm thinking it was a corner seal that gave out from the way it's running, but it could also be a cracked seal or burnt tip.



the engine has a 62-1 on it boosting about 15psi, decent size side port...





Do your side seals look like they have a lot of wear on them? also do you see a kind of crusty / kind of sharp lip on edge on the side seals where they make contact with the side plates?



Also from looking at the rotor housing in the pic's you posted on the other forum my guess is definitly heat. I've puled apart stock beat engines with 60,000 km's on them where the springs were damn near flat and the grooving looks a lot like what those engines have had. I'd look back at some of your data logs and see if there is a sudden jump in water temp during runs even though it may recover imediatly after the run.



I'd also like to know around where your HP is, port, engine oil you use, what oil cooler(s) your running and what oil your using in your premix?

Maxt

In regard to the springs, both batches I have had from Ra, needed to be rearced by finger to even meet min spring spec before installation when they were new, when you push the Mazda springs into place , it makes a definite "POP" when it clicks into place, even old mazda springs do this, but the RA ones make just a light flicking noise, like there isnt enough initial tensile strength in the spring, I had heard rumors that RA was telling people my first RA built motor was running hot, and my springs were flat, my car is hard pressed to break water temps of 185 deg F, my oil temps are 180 before oil cooler.. So I don't think its temperatures, I think its bad springs, along with incompatible seal materials...Keep in mind I live in Canada, and most of my RA seal running has been done in the cooler times of the year..(-5 to +10 C)

In between batches or RA seals, I ran a set of mazda 2 pc, the circumference length scratchmarks were not there with the mazda 2 pc's seals, the housings came out smooth and almost shiny with the mazda seal, everything else remained the same, so it definetly related to the material composition of the seals. I am running more or less the same timing curves I was before, a tad richer, from 10.8 to 10.4, my egt's are in the 725-770 C range on lean cruise, and are 675-725 so far on boost of 10 psi, driving around town the hover in the 500-600 range Pre- turbo. Nothing to crazy there, compared to my stock N/a those egt's are very mild, it runs lean cruise towards 900 and on power falls to mid 800's...

My last RA motor became a low comp problem at around 10,000 km's till about 9000 km's it was gaining compression every day. On this latest one, its at 2100 km's last night it cranked just over 100 per face, so I will have to see where it goes from here. Its gained 5 psi from its first hour of run time though..

You can tell if you have the seal warping issue, it takes on all the characteristics of running with a bad water seal but with switch in the hot/cold start difficulty, it will start fine cold, but when hot it will be very hard to start, and your crank rpms show up as about 50 rpm higher due to having no or low compression, one rotor will start to spit and catch, then it will start to run and slowly gain rpm, once it hits enough rpm the other rotor will catch, but it won't idle until your egt's reach 400 or so, or when the seal I assume is nice and hot and probably starts to go flat again..

The first set of ra's I had were totally all over the map spec wise, and they all wore at different rates, even seals that were on the same rotor were worn different, one hardly wore, but the second one had a sharp edge and was worn down immensley, the technique used to manafacture the first batch was not only all over the place in physical size, but I think in hardness to. But that problem has apprently been corrected by RA.. But face to face, there was at least double the seal deflection on the RA's than a set of 200,000 km mazda 2mm's that I know had been overheated more than once..Maxt

rx7will

I'm using the ra 2mm seals and springs in my TII and its doing fine. I drive it normal but took it to a track day at buttonwillow once. I recently bought a set of the ra 3mm seals but i am decididng if i want to run theses seals.

2a+RoN

hmm... I am starting to think I'm gonna get rid of my RA's that I got for my rebuild and just go mazda...

Drago86

My housings, which were in like new condition (only 60k), now look like this. RA seals have HUGE problems with adheasive wear. Not a well (at all?) engineered product imho.

Nospig

Nail marks of the devil ! Mazda spent a lot of time developing bimetal apex seals that didnt do that . The problem is a frequency vibration that occurs at certian rpm. In very early engines a small hole was bored through the apex seal so the vibration happens far beyond the rpm limit of the engine . Once the right bimetal combination was found they stopped with the hole through them . Use mazda apex seals . If you use other brands bad luck you get what you deserve .

Rotary shops with a back yard degrees should be avoided it just shows how amateur there operation really is and there lack of knowledge.

If there was a better material for apex seals dont you think mazda would have switched to it ?