I need to decide which style seal to use before I order a new backplate for my turbo upgrade. I have been told that carbon seals are only required for suck through carb setups, but I also have been told that all of the factory mazda hitachi turbos use carbon seals. So I'm not sure if I need to go the carbon way or not. I've already got a backplate with a dynamic seal so I'd prefer to use it if I can. If anyone can help me decide which way to go it would be appreciated. Thanks.

Perhaps I didn't make myself clear enough in my last post. I am NOT talking about apex seals (everone knows carbon apex seals and turbos don't mix anyway). Someone obviously thought I was because this topic got moved from the single turbo section to the engine building section. I AM talking about the seal which is between the centre oil housing and the compressor. This seal is in the backplate and you can get either the carbon or dynamic type. I just don't know which one I need. So could whoever moved this topic please move it back. Thanks. https://www.nopistons.com/forums/pub...#>/biggrin.png

haha, ok consider it in the turbo section :bigthumg:

Haha, whoops sorry :bigthumg:

Thanks. :bigok: Now that we've got that sorted out, does anyone here possess the information that I require? I was hoping the Turbonetics website had some info in the FAQ's but it doesn't. Is there anywhere else I should look?

You might want to give turbonetics a call or majestic turbo. I don't have the numbers handy, but it should be easy to find searching the web.

You cant use dynamic seal in the stock twins without some serious changes and custom parts. If you just want to do a standard rebuild you need to use the carbon seals.



STEPHEN

what turbo are you refering to anyways? are you doing this on the stock turbo?

draw through carb (suck through) requires seals that is more fuel resistance, since the fuel some times kills the seal.

the dual dynamic seals are very nice... they are quite reliable too.

Actually when you mentioned carbon seal I took for granted you were talking about rebuilding your stockers. Now that I looked over your post I dont think you are. What turbos are you building? Definatly go with dynamic seals. The only turbos I would do carbon seals with is the stock twins for a 3rd gen and thats just because they came with them. You cant easily switch over to a dynamic seal if the turbo was originally carbon. If you have the option definatly go dynamic



STEPHEN

Thanks fellas. Yeah, as you guessed I don't have the stock twins, just a smelly old TO4B compressor on a series 5 (89-91) rx7 exhaust half. Its got a dynamic seal at the moment, but the turbo guy was trying to talk me into using paying for a carbon one as its getting rebuilt. His only logic was that the stock Hitachi turbos had them so they must be some point in using them on a rotaty. But then I told me a whole bunch of BS so I wasn't too sure if I should trust him. After what SPOautos said and a few other rotary guys I've talked to I think I'll stick with the dynamic one.



I'm getting it rebuilt with a new 60-1HiFi comp wheel which I've already bought. I'm still trying to deside whether or not to machine the old housing to take the bigger wheel or fork out for a new one. Getting the right curve on the inside of the housing looks like it will be a mission.