Apex and side seals

[Lord Flash]

Hi All,I once owned a Mk3 Rx7 and had upgraded the rotor seals to NRS ceramic to cope with the increased turbo pressure and porting.I now own an air cooled commander engine which I've started rebuilding. The seals in the Norton are a form of steal. So to the question, is there ceramic alternatives for this engine?Regards Dave

[kanonkopdrinker]

I am sure there is a chap with a Commander currently running it on ceramic seals, but I cannot think of his name ....Somehow, the West Country seems to crop up?Anyone remember his writing about them?DC

[Lord Flash]

Hi AllI've been in contact with NRS Rotorsport. They've said manufacturing of Apex seals would not be a problem. However, they would require a minimum batch of 50. Also they didn't quote a price, going by the RX7 seals, they won't be cheap!Browsing the web, I came across the Axrio engined powered racing go-carts. They use what I presume to be an updated Sachs engine. This is water cooled but also uses internal charge cooling. It's just one rotor but measures 294cm3. It also comes with an option of ceramic apex seals.The question being, is the Axrio and Norton engines internally dimensionally the same and therefore we could use the ceramic seals?

[Richard Negus]

Yes, dimensionally similar and the seals are alleged to be interchangeable.Ceramic seals are £120'ish EACH and I believe they're one-piece construction although I haven't been able to see one.

[Joe]

Yes, I can confirm they are one piece. I spoke to a chap at the Wankel Treffen and he showed me a bag of three seals which he just purchased from Axrio and £120 each is about right. I believe also the rotor housings are available too and modified directly to fit Commanders for about £450. From memory I think the modifications are machining a grove for the water passage "o" ring and an adaptor plate for the inlet tube. It's a few months since I saw the rotor housing and I can't quite remember the details but the price is correct. Regards, Joe.

[Lord Flash]

Hi All,Awesome news many thanks. I'll contact them and buy a set then let everyone know how they go!Cheers all.Dave