Hey all,
Looking for some input.

I am trying to naildown my rebuild, and wanted to see what people would recomend for a few items.

1. A rebuild kit: I know atkins makes one, but Ive heard so many stories of this person doesnt include that or this, and onesie twosie starts to add up.

2. Apex seals: 2mm or 3mm? Carbon or Ceramic? OEM or Aftermarket.
Who makes them, where can I get them?

I plan on using a Borgwarner EFR 8374 hoping for 350-400ish HP on pump gass when its all said and done.

 

1. Mazda sells everything individually, so this is partly why the kits are weird, as they are pieced together by the vendors. Hence the variety.

2. Carbon seals are a no go for turbo cars. they are meant for a high RPM non turbo application only, or possibly a restoration with housings that aren't available anymore, like a 12A. Ceramic are a little bit in the same boat, but are strong enough for a turbo car, so they occasionally get used there, high cost is generally the objection.

which leaves steel seals. 2mm seals are lighter, and seal better than 3mm seals. the OE Mazda seals generally are designed to seal best and wear the least, but they are "brittle". the aftermarket seals tend to be "softer" so they bend instead of break, but they also tend to not be as nice to the housings, and they by design don't seal as well.

cliff notes, under 400rwhp, the OE seals are probably the best choice, from 400hp up, you really need to have you ducks in a row to have the OE seals work, so the aftermarket seals tend to be a better/safer choice

 

I use RX Parts seals exclusively in my single turbo builds. They are super strong, yet do not destroy the rotor housings like some of the other aftermarket seals.

3mm is a waste of time. It was a bandaid when no other stronger seals were available. The spring and heavier seal is more prone to chatter at high rpm and the larger surface area causes more wear.

Stock seals are great for near stock applications, but remember one good knock will break one.

I've used Atkins seals in non-turbo builds with very good results.

Ceramics and carbon are not ideal for a turbo application. They are great for na, high-reving motors.

I'm not satisfied with any off the shelf rebuild kit so I piece together my own. Let me know if you would like me to put one together from you.

 

And of course the 3mm seals will require additional skilled machining which will (unnecessarily) increase rebuild costs.

 

E&J seals. hit up addicted performance and they will hook you up

 

I would like to try their new 3 pcs apex seals, just not anytime soon

 

If you maintain your car well and run some water/meth injection, 2mm oem mazda apex seals. They have the best seal to housing interface.

I have tuned some single turbo oem seal cars and they run great. I have seen a lot of aftermarket seals last only 20-30K miles.

People say, do you want to see an apex seal go through a turbo?

I say, do you want to do rebuilds every 20-40K miles and ruin your housings and rotors?

I'll take my chance.

 

Do your research on seals. Just because a seal works well in a racing application doesn't mean it does well the the street. Just because a seal is "unbreakable" doesn't mean it will last long. 3mm is a waste of time. Plus 90% of machine shops can't cut the rotors true so the 3mm seal will chatter.

 

OEM seals work wonderfully in certain applications..... 350 rwhp, sure. 400 rwhp? maybe.

Anything more, not a great idea.

Stock FDs made ~215 rwhp. If you think you can make double the oem power with all oem internals, you've got another thing coming.

I run Rxparts seals in my single turbo black FD for a reason

 

https://www.rx7club.com/rotary-car-p...seals-1097504/