How much can a rotary take?
 

As the title states I just want to know how much abuse can a rotary take before it finally gives? My brother asked this question and i did not really have an exact answer for him so hats why I am asking you guys.

first off,
this is a very good question that will have many opinions, secondly this question will not be viewed highly by some members here so don't be offended if you get some ribbing over this.

OK my opinion and observation over the years is as follows....
all 12A rotary's should not exceed 7500 rpm wide open throttle for any extended period of time internal damage and failure will result.........small parts and small mass= engine failure. sorry just opinion.
13B should not exceed more that 8500 rpm for an extended period of time at wot. more stronger parts in this engine but will still break internally as well.

so these are the facts that have been said over and over, yes it turns hard but don't kill it. now lets talk reality. I have had mostly 13B engines in rotary pick ups and 7's. The quote......a red line a will keep the carbon away.........is very true.
I had a import 13B i put in my cream puff 77 repu and would turn it to 9500 daily for the 3 years I had it, never broke.luck I guess, I was just a stupid kid and new nothing about a rotary other than it really reved. my 85 gs 7 broke apex seals the second day I drove it trying to exceed 7500. So point being every engine is different, milage, maintance, prior abuse will kill or save a rotary, so your question will be open ended here.

It is totally erelevent where a rotary will fail, just don't do it as parts are getting harder and harder to find for earlier engine.......save as many parts as possible.

while not a question i like to see because it makes me think the person asking the question is going to abuse the car and engine and purposly attempt to destory one or both...but a lot of the answer depends on how well the engine has been maintained, overall internal condition, mileage, and modifications. there's really no way to tell when an engine is going to cough up a seal or lock up but the quickest way to lead to engine failure is lack of maitenance, improper mods and tuning, and general abuse and neglect.

the 7000 rpm redline is set for a reason. the apex seals begin to chatter at continuous use over 7K rpm and you will quickly see engine failure. 8500 rpm on a stock port S3 13B is suicide and should not be done. the engine fails to make power past 7K rpm so running it past redline is useless and just adds unneeded wear to the engine. the S3 13B does not have much stronger internals (forged parts) but it does have better internal oil lubrication.

It doesn't really matter in my opinion wether it is a piston or a rotary engine.....if you abuse them enough they will break sooner or later.

There are enough examples here of rotary engines that lasted, everything stands with maintanance and taking care of it but that goes for piston engines as well.

This is not me asking i don't plan on destroying the car or the motor, neither does my brother just a spark of curiosity that's all

+1

it's a loaded question at best - virtually impossible to answer with any amount of certainty. not only are there many factors surrounding the individual engine itself, and contexts of use, but the term abuse is too generic. what particular abuse are you referring to?

abuse and over revving is sure to cause engine failure..............ever heard one go POP? only = lots of dollars. DON'T do it

I was mainly talking about things like keeping it in high rpms, as if drag racing over and over again (like how many passes before he would have to rest) and to reduce it down we will say its an almost perfectly maintained motor 12A/13B no real specifications besides that though.

BTW this is all hypothetical

well, speaking hypothetically ... one has to keep a few major things in mind. the first is reality, the second is context and the third is common sense. drag racing your car in and of itself does not equate to the kiss of death for the engine. is it the healthiest thing? no. does it shorten the overall life? of course it does.

your question, as stated, doesn't take into acount that everything is relative. take one stock rotary and one built rotary, put them in the same car and go racing with them, you clearly expect the stock engine to fail first as it would likely have a lower threshold for the life of a race engine.

if you're drag racing with a stock engine, there are basic common sense modifications you should perform, you have to adjust maintenance to suit, you have to keep RPM in recommended limitations and you obviously have to keep it happy in terms of temperatures and tuning. follow that mindest and the engine will last longer than if you simply jump in dump the clutch and rev to the heavens in a cloud of tire smoke. how much longer is impossible to say.

By definition, "Abuse" is destructive. If you don't want to destroy it, don't abuse it. If you plan on abusing it, don't whine when it breaks.

It's not a horse; it doesn't 'get better' if you 'rest' it. Damage accumulates until something gives out, and any abuse causes damage - - just not always immediately-destructive damage.

Drag racing is a sport that should only be practiced by those who can afford to build spare race-built motors- - otherwise it's just wrecking otherwise-good engines to get your yayas out.

I know all about drag racing my cousin does it with a 13B and soon I will build a motor for it so do not worry about me destroying a perfectly good motor

these are tough little motors as long as you don't run em too hot, or run em out of oil.

a lot

http://www.youtube.com/watch?v=RhkAz6qossE

Thank you,

I've honestly never blown a apex seal out of a motor, in all 7 years of my short, lame rotary experience. But I've lost numerous bearings.. And, I actually have lost a apex seal, due to not running an air filter.

In a rotary, tempature is the enemy in my experience. It'll take overrev's here and there, just not every shift. Depends how it's built too.. There's just too many variables in this one.

You know what they say. They always run best right before they blow!

ive lost 2 i think?

the first was a stock Gsl-se, 211k miles, one day the oil seals didn't...

#2 was actually its replacement, another gsl-se, it did 130K of ABUSE. i let alex pfieffer drive it, between bogging in 3rd and overrevving second, he chose overrevving. like the tach is pegged @8k, and its still revving, overrevving.

it finally died when my friend took it drifting "on the rev limiter" which of course it didn't have.

upon tear down the only thing i found wrong was that the corner seal springs were like pounded into the rotors, very weird.

it was just a stock rebuild too, so nothing fancy, in fact it ran out of fuel up top too, so it would go down the straights pinging

whoa i didnt expect that

Yah, well, like I said, temp has always been my enemy.
Believe it or not I blew a water seal in my Monster Port yesterday in traffic..
Unbelievable, what a coincidence, I was just talking about failures yesterday too. Lol. But seriously..

sucks.... water seals are weird, pauls old FD engined FC would run on the track with 250F+ oil and water temps and be fine, but the 20B started using water without even being overheated

No,
looked it all over today and it wasn't water seals. They're good, turned out to be a collapsed oil filter. I lost oil pressure, and since it was running rough and had been running hot at the same time i assumed it was a water seal, so, tonight i put a mechanical oil pressure gauge attatched another oil filter i had on it and had good pressure, looked inside the oil filter and found my problem.
Sort of a crazy story but, being young i'm gaining experience.

And yeah, i usually never have water tempature problems, especially on my 13B PP that's in my and my grandpa's GT2 car. It's normally oil tempature problems you run into, because of the ridiculously high rpm you turn every shift, and how fast the revs climb. Even on a dry sump setup, which it has. I'm sure you don't have that problem on your PP since it's street driven, you can get away with about anything on the street. In my experience, which as i said, isn't much.

My car is heating up right now but thats because i have a bad water pump which should be getting here tomorrow

Never heard of a water pump going bad on any rotary TBO.

collapsed filter = fram? we cut a fram open once, not much filter in there....

yeah the oil temp on my PP seems to be ok, cereal box oil cooler duct and everything, it does help i'm only spinning it to like 6500rpm