3piece 2mm apex seals vs 2 piece 2mm
Hey, where did my $$$ go?
Joined: Feb 2001
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From: Bimingham, AL
Whats the deal with springs??? I see in the pic that RETed posted that the inner spring size is different.
HOWEVER, Brian from BNR just picked up a few sets today with the SAME PART NUMBERS and the spring grooves for the inner and outer springs are exactly the same size and in the same location as the old 3piece seals.
He picked up these seals on 10/17/03
STEPHEN
HOWEVER, Brian from BNR just picked up a few sets today with the SAME PART NUMBERS and the spring grooves for the inner and outer springs are exactly the same size and in the same location as the old 3piece seals.
He picked up these seals on 10/17/03
STEPHEN
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From: n
It might be a Euro thing...
And, just to **** things up, I just torn down another FC turbo 13BT, and one rotor had long inner springs, while the other rotor had short inner springs! The only history about this engine, is that it came from Germany, and possibly been rebuilt - there are signs of new parts on the engine (not necessarily internal engine parts). The apex seals all spec'd at the same height, so they didn't change those, but the apex seals did match the inner spring lengths!
-Ted
And, just to **** things up, I just torn down another FC turbo 13BT, and one rotor had long inner springs, while the other rotor had short inner springs! The only history about this engine, is that it came from Germany, and possibly been rebuilt - there are signs of new parts on the engine (not necessarily internal engine parts). The apex seals all spec'd at the same height, so they didn't change those, but the apex seals did match the inner spring lengths!
-Ted
The size of the inner spring has not changed since 86 when they changed to the 2mm 3-piece design. Mazda redesigned the new seals with a "shorter length" for the inner spring. Perhaps the seals you got that matched the old style are the Atkins 2-piece seals. Either way they still use the same inner spring which is part # N326-11-C04A.
Not sure where you are getting this "longer spring" unless its from an older carbon seal.
I have 3 sets ( 2 installed ) of the newer seals and all of them had the shorter inner spring length than the previous 3 piece design. One of them was with a single turbo and one was with a stock twin, but I ran them both pretty hard with no failures. I have a digital Mazda compression tester and they seem to seal with the same characteristics as the older 3-piece design. Usually after around 250-300 miles you get your "maximum break-in". I do a good "break-in" procedure at first that includes a lot of idle time.
This is what I have come across and feel free to correct me if I am wrong.
Not sure where you are getting this "longer spring" unless its from an older carbon seal.
I have 3 sets ( 2 installed ) of the newer seals and all of them had the shorter inner spring length than the previous 3 piece design. One of them was with a single turbo and one was with a stock twin, but I ran them both pretty hard with no failures. I have a digital Mazda compression tester and they seem to seal with the same characteristics as the older 3-piece design. Usually after around 250-300 miles you get your "maximum break-in". I do a good "break-in" procedure at first that includes a lot of idle time.
This is what I have come across and feel free to correct me if I am wrong.
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From: n
I dunno about that. 99% of the parts came from 1986-1991 RX-7's, so I don't think the cut-off is at 1986. A poster mentioned Euro versus US, so that might be it - I'm currently in the Czech Republic rebuilding a bunch of motors over here, so I'm outside the US.
I actually prefer the long spring, as it's a LOT easier to install, especially with oil coating your fingers trying to get everything seated correctly!
-Ted
I actually prefer the long spring, as it's a LOT easier to install, especially with oil coating your fingers trying to get everything seated correctly!
-Ted
