im ripping my motor out, because i lost compression on rear rotor...
im rebuilding it with the owner of a very good shop... and he mentioned throwing in 3mm seals..

im running a gt35 turbo (62-1 compressor wheel, p-trim turbine wheel, .84 turbine housing)

i was running 10psi on my 2mm motor... at about 280-300whp....

i have all the required mods for running more boost (pump, injectors, microtech, etc)

i was thinking of upping the boost to 15-17psi... hoping to make 380-400whp? and am wondering whether i should put in 3mm seals?

what do you guys think?

 

I would do Atkins 2mm seals! I don't for see a reason why anybody would need to go 3mm with how strong they are!

 

3mm is un neccessary

 

2mm rotary aviation seals seems to be working out for me

 

if your apex seal slots are still within spec, i can't see why you'd want to want to machine perfectly good 2 mm rotor for 3 mm seals - especially for 400 horses. put your time and money elsewhere.

 

My oem 3mm seals already saved me one motor... Anyone that says they are not worth it has no idea what they are talking about. Unless you are not going for high power then yes they are not worth it. That is the only case!

 

They haven't used Mazda OEM 3mm seals since around 1985, so I don't don't why you would use those. As far as using 3mm seals, they only reason to use them is when the rotor housing is worn down too much to use 2mm in my opinion.

There are several people using 2mm seals in 500 - 800 hp applications. After all, Dee from Reactive Racing uses them and I would trust someone who ran a 7.49 1/4 mile time with a 2 rotor!

 

2mm mazda they are the best

 

You mean that they would switch to 3mm is that the rotor itself is no longer within spec I hope. If the rotor housing is worn down its worn down 3mm seals will not help.

Yes there are several people that used 2mm seals with great success. Though they have gone to great lengths to make sure everything is properly performing and have spend very good money on tuning.

I for one just had sent my injectors back to kg thinking one of my primaries was leaking at idle. I thought while I was at it why not send my 1680's in. A week later I get a call from Sal informing me that my one 1680 was running 9xxcc.

Now before I knew about this injector there was a night I got a strange spike up to 15lbs and I swore up and down that road I detonated (most likely cause of that injector). If I had 2mm seals in they would have for **** sure blown to pieces.

As I stated the 3mm seals are almost a failsafe to a tiney bit of detonation. Thank god I'm not retarded and turned up the boost and romped all over town. But my lesson is that the 3mm seals paid for themselves by saving me another rebuild.

Like I said Dee and many others are an exception to the rule as they have invested high dollars into their setups. 3mm seals are good for the guys like me that cant always have brand new parts or know everything will always perform as intended.

Let the debate begin...

 

there are some people that really like the 3mm seals for the added mm of protection. Infact steve at gotham racing likes to put 3mm seals in customers motors and I would trust him above just about anyone however there are tons of people running 2mm seals and doing just fine with them at very high horsepower levels. I think steve puts the 3mm seals in there for a safeguard against stupid people getting cocky with thier boost and uping it above what he tuned for. That could be off but I doubt by that much. All these guys running 7 second quarter miles are all running 2mm seals so I don't doubt them at all. It's all in the tuning!

 

So that means after 1985 they are expired or out or service?
In that case I guess the three piece 2mm apex seals are in the same category then!

In actuality it's quite the opposite not to mention any worn out rotor housing is not good for any type of apex seal although the best seal for a worn out housing would be the factory three piece 2mm apex seals.

So would you also base your choice on ecu, fuel type, sparkplugs, etc. on the results of a 1/4mile racer?
In that case I guess what about the other 100 successfull racers that are using 3mm apex seals?
Ever heard the term "Performance beyond the 1/4mile".

This 2mm vs 3mm debate will go on till the end of time.
Lets way all the facts now.

Mazda no longer makes the 3pc 2mm so any benefits those offered are out the window now.
Presently available form factory would be 2pc in 2 and 3mm sizes.
Both seals offer advantages over each other.
It's up to you to decide what works best for your application.
If you're looking for strength vs detonation then the 3mm wins.
That is not saying that a 3mm won't break if it encounters detonation but it's more tolerable of slight detonation vs the 2mm.
As for the sealing aspects of both seals. That's up for debate based on the present designs being of the same except for the RX-8 apex seals which would be another avenue for debate.
Now if RPM use was brought into the debate then the 2mm offers some advantage for extreme high rpm use. Now what's your opinion of high rpms is another debate all together.

 

Im pretty sure the MAIN point why some people go with 3mm is when the rotors are out of spec and dont want to buy new rotors. This damn well should be the only reason for 3mm because 2mm can handle plenty of HP. So ya.....f- 3mm.

 

all the big tuners i read about tune on 2mm oem's

 

Hasnt this topic been discussed a million times before.

 

it'll be discussed a million times after this, too.

 

[QUOTE=MichaelB145;6969858] As far as using 3mm seals, they only reason to use them is when the rotor housing is worn down too much to use 2mm in my opinion.



I did mean Rotor is worn, not housing....


Crisspeed....so you must be a fan of 3mm seals? This makes it tough as I would trust your judgement on this subject too! At what point do you feel that 3mm is best?

 

3mm is great if your learning to tune yourself or your tuner is incompetent. That little extra protection against detonation can really pay off, literally. But if you have a tuner that knows what they are doing then 2mm is the choice.



Oh yeah, I'm sure a SEARCH would have come up with plenty on this subject since this topic has been debated countless times before.

 

fine. maybe i don't know what i'm talking about. it's a distinct possibility and for some things, you're absolutely right. but for me (and all the real reliable, high horsepower guys that run 2 mm seals), it's cool and we'll just beg to differ with you.

 

I'm stated pretty much one opinion and Crispeed just gave more info and clarified for me (thank you). They are out there for the boneheads (I consider myself a bonehead) that don't have perfect parts or perfect tuning.

Simple sacrifices are higher wear rate with 3mm seals and slightly lower sealing capability. Though at higher rpms (I believe) the 3mm seals actually seal better with their mass and centrifugal force.

Diabolical I'm not saying you have no idea what you're talking about. With the majority of the idiots posting on here (myself) there is a need for more protection. So any advantage you can have I believe is worth every penny.

Like I said, they already saved my motor...

 

2mm seals+tuning tuning tuning

 

3mm ceramic seals, only $3000! w00t

 

yeah get those if you have 8 katrillion dollars for a rebuild. Of course the seals will outlast the motor so you can just re use them in the next rebuild

 

We need to talk For $3600 I'll sell you 3 sets of 3mm ceramic seals

 

2mm Atkins (or OEM) cryogenic treated seals FTW!

Just try to break them... just try.

 

^ Ok I'll just detonate once...

There are no apex seals that are bullet proof, they will all break. I invested money for 50% stronger seals and I got it.