Which is better, 2mm or 3mm apex seals, pros and cons please??
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Joined: Apr 2010
Posts: 231
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From: Gig Harbor, WA
Which is better, 2mm or 3mm apex seals, pros and cons please??
I would appreciate some feedback, this question could probably be for all rx7's but i have a 1991 so I just posted it here
not to hate but there is a search button....
2mm pros:
less mass
dissipates heat quicker
seals better
no cost to machine the rotors
2mm cons
weaker and more prone to breaking under detonation (a good tune completely removes this issue)
3mm pros
stronger out of the box
3mm cons
retains heat and will warp with very large exhaust porting
doesnt seal as well
more mass
extra cost to mill the rotors to accept the 3mm seal
that about sums it up from my point of view, everyone has their opinions....i prefer 2mm
2mm pros:
less mass
dissipates heat quicker
seals better
no cost to machine the rotors
2mm cons
weaker and more prone to breaking under detonation (a good tune completely removes this issue)
3mm pros
stronger out of the box
3mm cons
retains heat and will warp with very large exhaust porting
doesnt seal as well
more mass
extra cost to mill the rotors to accept the 3mm seal
that about sums it up from my point of view, everyone has their opinions....i prefer 2mm
Rotary Enthusiast
Joined: Sep 2009
Posts: 884
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From: Omaha, Ne
not to hate but there is a search button....
2mm pros:
less mass
dissipates heat quicker
seals better
no cost to machine the rotors
2mm cons
weaker and more prone to breaking under detonation (a good tune completely removes this issue)
3mm pros
stronger out of the box
3mm cons
retains heat and will warp with very large exhaust porting
doesnt seal as well
more mass
extra cost to mill the rotors to accept the 3mm seal
that about sums it up from my point of view, everyone has their opinions....i prefer 2mm
2mm pros:
less mass
dissipates heat quicker
seals better
no cost to machine the rotors
2mm cons
weaker and more prone to breaking under detonation (a good tune completely removes this issue)
3mm pros
stronger out of the box
3mm cons
retains heat and will warp with very large exhaust porting
doesnt seal as well
more mass
extra cost to mill the rotors to accept the 3mm seal
that about sums it up from my point of view, everyone has their opinions....i prefer 2mm
Do 3mm seals really help detonation problems that much? I've heard from some people that it's not worth the money but others swear by it. Would it be beneficial if somebody was boosting high compression rotors?
i believe its NOT worth it, the only time its "worth it" is if you have a set of rotors that are good except the apex seal groove is badly worn and 3mm will fix it...thats about it, high hp engines..forget about it
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also there is the fudge factor of machining rotors to take 3mm seals, it needs to be very precise.
Outside of North America, no one is converting to 3mm seals. Probably tells you something. If it was that great, wouldn't it catch on in Japan and Australia and other places with active rotary communities?
Like said before they both have pros and cons. I personally like the 3mm seals. Went through 2 engines with 2 mill both with good tunes. Only lost the the 3mm engine due to rear bearing spun. All the seals are still good gonna just reuse them when I rebuild it.
i got a built up jdm S5 TII motor a few years ago, and has ran awesome the whole time, i pulled it apart to freshen it up and it has 3mm seals amongst other things
