RotaryEvolution

iTrader: (30)

guessing one of those long florida bridges?

seandizzie

iTrader: (1)

Na some ******* in a Dodge Charger with flashly lights.

fendamonky

iTrader: (6)

^ Hehe, I was going to guess that.

The important question is.... Was it worth it?

fcrotory

iTrader: (20)

So I'm gonna throw my 2 cents in here.
All the guys that said the RA seals has killed there housings. Were these motors completely balanced? And what tolerance are your end plays being set to? I'm on my first set of classic seals with my first build. It's has started every time(hot or cold). I've got 900 miles on it and 6 days of drifting abuse. Oh, and im using 9.4:1 rotors on 8psi and 1.5:1 premix of Redline synthetic. I didn't have mine balanced but I guess I did something right. I just ask because you would think with those seals you would wanna make sure everything is perfect. To prevent said failures.

fendamonky

iTrader: (6)

^ Um... 900 miles is nothing to boast about on an engine. Hell, I'll be BREAKING IN my new engine for longer than that...

fcrotory

iTrader: (20)

Is yours also a high comp ratio? I did no break in time. It saw boost after 100 miles. I have video to show how hard I abuse it. I'm amazed that it lasted all season. 900 miles may not seem like alot on the street. But the only street driving my car sees is a trip to the track. I guess I can't really tell you what the inside looks like till it blows....but you guys will see pics when it does.

fendamonky

iTrader: (6)

Yes. I'm using s4 na (9.4:1) rotors that are lightened, clearanced, and balanced.

That's brilliant! I bet your engine runs better than perfect!

fcrotory

iTrader: (20)

I like your sarcasm. Good luck with your build smarty pants.

fendamonky

iTrader: (6)

Thanks

Though, you can keep the luck... I have a feeling you'll need it more than me.
(Unless of course you used the magic Puerto Rican pubes during your build... In which case that keg will be unbreakable!)

fcrotory

iTrader: (20)

Only luck needed is before first start up... All I'm saying that if the engine is properly built, there's less likely a chance of failure. IMO, if she starts and runs and drives. She's gonna stay that way unless something catastrophic happens, like starved of oil or fuel or improper tune, etc.

fendamonky

iTrader: (6)

Yeah... No luck involved for me on that... It was about 5-8 hours of prepping the rotors, and making super tight tolerances before stacking it up. You're welcome to check my build thread on the other forum.

If you're running sloppy tolerances and you don't mind rebuilding every 5-10 thousand miles than skip the prep and break in. If you're running tolerances down to .002" (or less) than you're going to need that proper break in. Sloppy and loose is another story... But I like my women like i want my engine: tight, well made, and built to perform. If you like 'em sloppy and loose than it's all you

RotaryEvolution

iTrader: (30)

what does end play and balance have to do with the seals digging into the housings?

i'm fairly sure my previous assumptions on the subject were as close to a real answer as you will get.

fcrotory

iTrader: (20)

I used a mazdatrix rebuild video to build my motor. I used there race specs and tolerances for everything. I am a amature. I'm no expert at all. Like I said. It was my first build. I've also read a dozen different break in methods. And that's just the one I choose. I never doubted how you built your engine.

I imagined that if it wasn't properly balanced it would cause more damage to the housings regardless of what seals right? I'm not really sure... Just what I thought lol Can you explain why it doesn't have anything to do with it? I would appreciate every bit info possible. I love learning.

mannykiller

iTrader: (93)

^0.002... Your crazy imo. Seems a little excessive IMO but let us all know how it turns out.

fendamonky

iTrader: (6)

I'm def gunna bow to your assessment, since i think you have a wee bit more experience than me

The off topic pissing match was just that, off topic! Lol

Hehe. Mazda factory specs are from .002 -.0059. Brian (TitaniumTT) had been running super tight clearances for a while (on his track car) and it'll run all over most. The break-in period is just really important though because everything IS so tight.

sleeper7

Agree with this except the end play thing.
Is what we have been seeing with 2mm seals at high rpm and load is the e-shaft starts to move around and cause the rotor tips to contact the housings. Vibration can be caused by many things. There is a solution to this that does not require balancing the rotating assembly.

RotaryEvolution

iTrader: (30)

i have seen the clawed up rotor housings in rebuilt engines running stock parts that had showed no signs of it before the rebuild. those engines also have not been pushed nearly that hard, ie no rev cuts or boost cuts or over revving.

no super tight nor super loose tolerances, only variation was different seals than OEM, resurfaced housings and some time(keep in mind i have also seen OEM seals do it as well).

resurfacing does also not mean that you have to machine your housings, i have seen people scuff them up with various materials which removes the smooth surfacing.

also the cases i saw, the rotor tips were perfect on. no contact between rotor and housing.

i'm sure in cases where the rotors are contacting the housings you will see some additional damage but the damage is almost always localized, because the seals get jammed into the rotor, so how can they continue to wear the housing? 2+2 doesn't add up to 6.

fcrotory

iTrader: (20)

So are you saying that its not the RA seals themselves that are giving everyone a bad idea on em? But more or less how you take treat your seals? From what I read, it looks like proper use of a air filter and the right 2 stroke/amount will do wonders.

seandizzie

iTrader: (1)

Yes it was.

GoodfellaFD3S

iTrader: (213)

I believe he's talking mm of clearance for side seal to corner seal.

I've run even tighter, leads to less blowby, less fuel dilution in oil, better compression. There are ways to do it without issues.

Btw, not to rain on anyone's parade, but in a lot of these engine building discussions it would probably be appropriate to state some kind of hands-on credentials: ie, I have built one engine vs I have built 200 engines over the last ten years <-----just an example. Reason I mention this is because the average reader tends to take what people post as gospel if they 'sound like they know what they're talking about' when in reality that might not be the case.

Just some thoughts I had while perusing this thread and another thread over in the 3rd gen tech section.

fcrotory

iTrader: (20)

I'll take advise from Rotary Evolution and a handfuls of other guys on here. I like to ask questions. And I wanna make sure I have the right people answering them.

fendamonky

iTrader: (6)

Right on

Yes, I was referring to the clearance between the side and corner seals. I should have specified that.. Truthfully I'm not sure off the top of my head what we did for clearance on the apex seals.

Hell, you and Ihor saw the amount of blowby I was having when I brought my car in to you in July of 2011.. I don't remember what the clearances on that first engine were, but the second one built by the same shop (which we tore down in my garage) had gaps big enough to practically fit a coin into!!! Clearances that loose had me emptying my (full) catch can every couple hundred miles...

Yeah, I'm definitely NOT a professional engine builder. I've just had a series of bad experiences with "professionals" in the past couple years and have had to learn some hard (expensive) lessons as a result! Any advice I give is with the intention to save other members from making the same mistakes I did, hopefully saving them from costly lessons.

I've only been personally involved in one rebuild, and that was mostly a learning experience (I let Brian, from Speed1, and my buddy Mike, the NASA engineer, do the detailed work on that one) that I absolutely appreciated!

Hopefully I won't be working on another rebuild (for my own car) for several more years!! lol

RotaryEvolution

iTrader: (30)

10+ years with rotaries only, 200+ rotary engines.
12+ additional years working in heavy duty automotive(engines/transmissions) at the auto dealerships.


years of experience don't always mean much though. i know i may say some stupid things from time to time, you shouldn't always trust what you hear but if several people start to say the same thing you may tend to believe it. sometimes it's good to just use claims as a reference point for testing on your own.

seandizzie

iTrader: (1)

Wanted to share that the rotor bearings are about shot as well. You can see the copper/ brass looking color showing through the bearing. Need to get a bore gauge and see what the clearance is, bet its way out...

"not to rain on anyone's parade, but in a lot of these engine building discussions it would probably be appropriate to state some kind of hands-on credentials"

- In my case I have built about 6 rotary engines for my own car, took 3 of them to learn how to tune it. I am not a pro and don't claim to be, just sharing what I have experienced, learned alot about what NOT to do. I love these little engines, making that much power out of such a small package is just fun... If I can learn more by sharing my mistakes, I have leaned more, if it helps others as well learn too, thats even better. Most of my knowledge I gained from working at Suncoast and old buddies, plus Barry showed me alot too.

As to the side seal clearance, someone had a thread about 0 clearacing the side seals by cutting the corner seals and allowing the ends of the side seal to rest in the corner. I think Lynn Hanover and Barry Bordes are running engines this way. This seems to be a good Idea. I am wanting to try this method.

RotaryEvolution

iTrader: (30)

i prefer tight tolerances on the running seals. for high revving engines i prefer loose rotor to engine tolerances, ie cutting the rotor tips off and shaving the sides of the rotors.

with the 2 piece seals you are much less prone to dropping a seal out of the apex seal slot, a few mm of clearance may save you a few days time, a rotor or 2 and a set of seals. but that is only if the engine twists marginally. detonation/preignition is going to do something, but you may get by a few passes with proper precautions before you realize and correct the mistake.