That's fine but buy only Mazda carbon seals! I'm not even sure anyone else makes a carbon seal but the point is that if you can't afford an Ianetti seal, it better have come from Mazda. I put absolutely zero faith in ANY other company's seals regardless of who has used others with good success.

 

I guess the question I'll ask you, Rotarygod, is: Are carbon seals streetable? To the affect of a 3 rotor all motor setup with semi-PP's, and a healthy street port on the original ports?

And when I say streetable, not 365 days a year driving, but warm/no snow days, and drivable around town? Or am I going to lose compression on them quickly?

 

Taken from the Mazdatrix site:

"Note: The carbon apex seals are designed for racing only. They seal better above 8k rpm due to their lighter weight. They do NOT last very long (20k miles on the high side), and do NOT seal well at low rpm's (like starting and at idle).
Not recommended for turbo, supercharged, or nitrous engines."

 

Depends on 3mm or 2mm.

I forget which thread it was, but it came out that the 2mm carbons wear significantly faster than 3mm carbons. A millimeter per hour of use at high RPM, I think.

Ferrous 2mm seals seem to track well. I had two iron seal 12As over 8500 once, and they both failed the same way... drove home fine, drive to work the next day fine, first time exceeding 6200rpm the engine lunches. It's like the five point palm exploding apex seal technique.

On the other hand, Ive had my Atkins 2mm sealed 13B past 10,000 on occasion, used 9200 as a shift point at the dragstrip and routinely saw the tach swing past 9000 when stretching a gear out at an autocross instead of upshifting, and they mainly died due to dust wear, not outright failure. The apex seals were 1.6mm thick when I was done with them

 

Just as a counterpoint regarding stock Mazda 2 mm seals, I run them in my 1/2 bridge. They seal very well all the way up over 8,500 rpm and I have taken them over 9,000 under acceleration a few times with no issues. Compression is still very good even after 4 years of races and a ton of back firing as we worked out the tuning bugs. I am scared to take the motor apart as it runs extremely well and pulls hard from about 3,000 rpm to the 8,500 rpm redline.

Once, a co-driver missed a shift and the motor singed to well over 10,000 rpm with no obvious issues (gotta love tell tale tachs). The car has run for 3 years after that event, so I think its still okay.

My buddy who runs a PP 13b, grenades his carbon seals quite often and is getting a bit tired with the occurances. Maybe the fact that he pulls the engine to over 10,000 rpm constantly might be a factor, LOL.

Anyways, I really like the stock Mazda seals for up to 8,500 rpm use, durable and good sealing.

Eric

 

ive been in enjoying my RA classic seals, at rallyx it sees alot of 7 to 9krpm. solid compression runs great! but I am only using these because I found them in an engine i took apart

 

I've had the classics in my 91 vert since 05. That engines got 45k on it normal driving. How many miles on yours? As heavy as they are, I would have never expected them to seal well up to those ranges your running.

 

They work fine on the street, but like mentioned they will wear faster than other seals but in return cause little wear on housings unlike the steelies. If you're just going to drive it here and there, they will last you years and years.

I have raced my 12abp with carbons for over three years at over 10krpms with no problems. Sold the engine to a friend and it is still going strong. The reason your buddy is "grenading" his apex seals is because he is either not clearancing them correctly, not chamfering his closing edges on his porting, or is detonating because his tune is not right. Look at the video in my sig. That is launching off the rev limiter of 10,200 and shifting at just over 10k. Engine keeps making power for over 3 years now.

 

What I have heard about 3mm carbon seals is that you can expect six hours of use over 10k before they are worn out.

Six hours is five or six years' worth of drag runs. Six hours is also two trackday weekends.

My Atkins seals were worn out junk after two years, but that was probably 45-50k worth of driving in addition to the fact that their eventual death was due to dust ingestion, not really wear. The fastest wearing part of the seal was where the springs rode, not the housing seal surface or the sides.

The rotor housings are still in good shape, incidentally. A little wavy from dust, but not scored. I'll smooth 'em out and run them in the next engine, since I like the exhaust port shape in them.

 

I agree with you to some extent, but I also think that Peejay makes a better point. The motors are being built with all "New" Mazda parts and are being built by a race engine builder with over 20 years experience. What he has found is that for the first few weekends and test days (3 hours of track time a weekend) everything works great and the motor just flies in the car. Then, when the motor starts to go soft he knows that he is on borrowed time. He has learned from hard experience, that when the engine starts to go soft the motor has to be pulled out for freshening. This requires new seals and springs. If he catches things well, then everything is okay. If the engine goes soft in the middle of a 20 minute race and he can't catch it, pop goes the motor.

He has continually threatened to pull out the PP and stick in an all alu LS1. Maybe the next time it goes he actually will.

I also think that when he is in a draft and the motor pulls to over 11,000 rpm, this also contributes.

Eric

 

It wouldn't take too many expected refreshenings for ceramic seals to be justified cost/benefit wise.

This assumes that the rest of the engine holds up well enough. My personal experience is that the apex seals are the LONGEST lived parts of my engines Just a little dust and everything on the sides of the rotors get wrecked... including the side housings. (But hey, at least I have defined the problem!) And if you're buying aftermarket, or carbon-aluminum, the oil rings are more expensive than the apex seals!

 

Who Told you that? you crack me up jay...

 

I don't see how you can make a narrow-minded statement like this. You may as well have ended your post in

-Ted

To say that other manufacturers' seals don't have their place in some applications is ignorant to say the least. Now, if you're talking strictly for street-driven N/A application, then that's another thing.

 

You do know this is the NA sub forum right?

 

That's my conclusion. Just save your money and buy a decent set of 2 piece ceramics. They will pull more compression than other seals and will last virtually forever if clearanced and tuned correctly and cause little to no wear on housings.

That's common knowledge bro. If you feel otherwise then put some OEM metal seals in your all motor car and wing it to 10k for a couple of seasons(if it lasts that long) and tear your motor apart and see what your housings look like.

Here's a good read for you from racing beat. Notice when they list the uses for the "stock" iron seals to "never exceed 8500 rpm's".

http://www.racingbeat.com/mazda/perf...ine-seals.html

 

My motor took 9954rpm and survived. I probably still have the datalog, I have 200mb of datalogs in my tuning folder.

 

Um. Ceramic apex seals plus new housings is going to run $3500-ish. Atkins seals are $400-ish and you can run used housings. Even if you wanted to get spendy and run Mazda OE seals, that's still "only" $700 or so.

50k street miles plus track time is a very good life for a performance engine. Even the way I drive, that's two years' worth of use.

If I'm going to spend $3500, there are going to be pistons involved. Pistons and a quiet power that gets a lot better fuel economy. I don't think I've spent $3500 on engine parts *in ten years*... and most of what I have spent was on buying core engines. I have five engines' worth of good 13B rotor housings, but .very few good side housings and only two good rotors, and those are suspect because i had to replace the bearings in them and I've seen too many rebuilt engines with spun bearings.

Contrast with 12A stuff, where I have zero good rotor housings or rotors, and a cornucopia of good side housings.

 

I think there is more to apex sealing and correct tracking of housing. Like fact that apex seal is gas seal.... different materials, different use, maybe different clereances to allow good function at certain circumstances.

 

well back to my build! logan finished my exhaust system. here are some pics, should be here by end of the week i hope.

 

That exhaust looks so awesome! Does logan build a bolt on exhaust for the fc? It isn't on his website i don't believe. If he does that would be awesome

 

I found my RA classics in a rebuilt engine that was blown up that I picked up, mileage unknown.

I dont have a spedo so I dont really know, but I keep track of how often/much I fill up. It gets routinely drifted at test and tunes and then thoroughly flogged at a rallycross each month. It does 9kprm no problem. I have about 10-15k on it now with 100% used parts (aside from wet seals) I probably daily drive it 1-3 days out of the week.

rarely it will see 10krpm

hell my rotor has a hole in it too...

Its been running since mid march of 2010 and its been over a year and has only lost 10psi on each rotor (90psi f/r)

I just let it run alot and start it from time to time when I don't drive it.

I just run only rotella T diesel engine oil and change it frequently, oil pressures are good too. even at that high rpm with a used NA oil pump, no spiking no nothing.

 

no he does not. its made to order per your specs of your motor build

 

What was your 6 port setup jorx7 ? I plan to build my 6 port and i want to know wich setup is the best !

thanks

 

my 6 port was aux ports removed, vdi wide open, throttle body mod,msd ignition amplifier pre mix, block off omp, and all emissions, ac removed,electric fan,solid motor mounts, trans mounts, short shifter, apexi pfc ,banzi kit, full tune 185 190 to the wheels, stock block, though if i did it now i would install the acux ports sleeves from atkins as they are proven to up the ponys a couple.

 

ok thanks. its prety good numbers for stock port ! so if i plan to streetport my 13b I could expect close to 200 wheel hp. And you ran with the stock fuel pump and injector ?