think my ka24de can rev up to 9000 and stay there for 10 minutes

[mirra32]

wow is all i had to say about this video...

http://media.putfile.com/89_RX7_pop

if you must delete this just though this was crazy..and also stupid *** shietzz

[InsanityInc]

This really isn't that impressive. You have to understand something about rotaries. They're inherently overerdriven due to the design of the eccentric shaft, so if the flywheel is going 9000, the rotors are only going 3000.

[9240sx]

Try it!!Let us all know what happens.J/K

[AltiNate]

Seems to me that it was a perfectly good motor. Why they decided it would be worth blowing I don't understand.

so, insanityinc, the engine was only going 3000 when the tach said 9000?

btw do all KAs have rev limiters? My Altima does at 6250.

[InsanityInc]

Seems to me that it was a perfectly good motor. Why they decided it would be worth blowing I don't understand.

They said one of the rotors was blown, which was probably true considering it wouldn't reach redline until they had it going for a while, at which point the extra heat probably worked to create a seal in the blown rotor.

Quote »so, insanityinc, the engine was only going 3000 when the tach said 9000?[/quote]Yes, that's how rotaries work.

[HashiriyaS14]

13b's sound hella cool...

[ArticDragon192]

For every three turns a rotor makes, the "crackshaft" turns once.

[AmoebAssassin]

This really isn't that impressive. You have to understand something about rotaries. They're inherently overerdriven due to the design of the eccentric shaft, so if the flywheel is going 9000, the rotors are only going 3000.

Actually, it's the opposite. Rotaries are underdriven, meaning that if the crank is going 3000rpm, the rotors are going 9000rpm. The reason rotaries can do this is that there are no reciprocating parts in the engine, ruling out fatigue due to shock loading on connecting rods, and also because there are 3 total major moving parts in a 2-rotor rotary block. That is why rotaries can do that.

[MinisterofDOOM]

Actually, it's the opposite. Rotaries are underdriven, meaning that if the crank is going 3000rpm, the rotors are going 9000rpm. The reason rotaries can do this is that there are no reciprocating parts in the engine, ruling out fatigue due to shock loading on connecting rods, and also because there are 3 total major moving parts in a 2-rotor rotary block. That is why rotaries can do that.

That doesn't make sense. The crankshaft is smaller than the rotor's drive gear. Go look at a bicycle. When a big gear and a small gear are connected, the smaller one must turn more rapidly to match up.Also, if rotaries were underdriven as you said, they'd be about the torquiest and lowest-revving engines around--which is exactly the opposite of what they are.

The rotors rotate once for every three crankshaft rotations.

Google "wankel 3:1 gear ratio" and you'll find reputable sources confirming this.

[ArticDragon192]

http://auto.howstuffworks.com/rotary-engine7.htm

Haha, I had it the other way around, For every three revolutions of the output shaft, the rotor spins once.

[1998S14]

so since after one minute I got bored watching it and shut the window, I was wondering does it end with parts flying and the idiot standing next to the vehicle loosing a nad, just curious????

[AmoebAssassin]

That doesn't make sense. The crankshaft is smaller than the rotor's drive gear. Go look at a bicycle. When a big gear and a small gear are connected, the smaller one must turn more rapidly to match up.Also, if rotaries were underdriven as you said, they'd be about the torquiest and lowest-revving engines around--which is exactly the opposite of what they are.

The rotors rotate once for every three crankshaft rotations.

Google "wankel 3:1 gear ratio" and you'll find reputable sources confirming this.

You're right, my bad...it's been a while since i looked at that howstuffworks article

[s13rb25det]

either way , rotary engines suck!! they have zero torque and and explode all the time!! I work at a ford/mazda dealership and we are always working on rx7s! even the new rx8s are falling apart!! and parts are not cheap either! $185 bucks for 4 plugs for the rx8!!! super stupid!! if I wanted to have low torque and high revs Id get a super bike!

[InsanityInc]

either way , rotary engines suck!! they have zero torque and and explode all the time!! I work at a ford/mazda dealership and we are always working on rx7s! even the new rx8s are falling apart!! and parts are not cheap either! $185 bucks for 4 plugs for the rx8!!! super stupid!! if I wanted to have low torque and high revs Id get a super bike!

Uhm... you do realize that reduction gearing can easily be used to change the torque output of an engine, yes? And that they ARE, right? Just look up the gearing for an RX7 or RX8, you'll see. And rotaries aren't particularly failure prone when compared to other engines, they just tend to wear out faster, but considering it costs like 50 bucks to rebuild them, it's not too much of a problem.

[s13rb25det]

ooohhh, so all the rotarys I have removed and replaced really didnt blow up!! because on paper you say they are great engines! and $50 bucks for a rebuild!!! whaaaat!!!!! mabye for a oil pan gasket!!! the rx7 owners would be thrilled if parts only cost that much!!! any way Im not here to argue Im just saying AGAIN, that rotarys suck!!!!

[dickie]

the mazda tuning shop owners and techs next door to me would disagree with you. the engine is exotic so yes, parts are more expensive, and i have seen just as many chevy 350s, honda b18's etc... blow up. theyre not crappy engines if you know what youre doing, or else why would they still be making them.

i would trust the opinion of a guy who owns and runs his own shop over a dealership employee anyday, because how well he knows what he is working on determines whether he will stay in business. dealership flunkies, unless they are at the top of the food chain, not so much. these guys have been doing brisk business since 1989 so they must be doing something right.

i dont know, i drove an 87 rx-7 for three months ( my friends car) we revved the **** out of that engine, that was the original engine and never rebuilt, and it never gave us a single problem. still runs great today

[Dopefish]

either way , rotary engines suck!! they have zero torque and and explode all the time!! I work at a ford/mazda dealership and we are always working on rx7s! even the new rx8s are falling apart!! and parts are not cheap either! $185 bucks for 4 plugs for the rx8!!! super stupid!! if I wanted to have low torque and high revs Id get a super bike!

Hello Mr.Misinformation.... do you own an RX-7 or any other rotary powered car? Are you an ASE and Mazda Master Rotary Certified Technician? If 'no' was the answer to these two than you need to withdraw your comments now because you have no right to slander a motor you know nothing about.

The rotary is finicky, if you dont treat it right you will blow it, that is correct. Most conditions I've heard of with the RX-8's are similar to the primary failure points of the RX-7's. Owners dont properly warm up their vehicle, dont follow proper break-in and maintenance intervals, some may even drive the car so 'softly' that they experiance carbon-lock which can damage the apex seals if not properly handled.

I'd also like to not that $185 for sparkplugs is your dealership charge, anyone who considers that a normal price is worse off than I thought. I replace my spark plugs every other oil change (oil change: every 2,000mi) and it costs me $1.89 per plug for my NGK BER9Q plugs. The RX-8 iridium plugs cost about $45 a set outside of dealerships but I consider platinum and iridium plugs useless anyways and have had much better experiance with my coppers.

Uhm... you do realize that reduction gearing can easily be used to change the torque output of an engine, yes? And that they ARE, right? Just look up the gearing for an RX7 or RX8, you'll see. And rotaries aren't particularly failure prone when compared to other engines, they just tend to wear out faster, but considering it costs like 50 bucks to rebuild them, it's not too much of a problem.

Good work on the gearing info. As for rebuilds, they are indeed quite costly, its just the number of *main* parts is low. Bearing rate is almost null due to the low side-to-side force impossed on them. The main cost is the seals, which is costly from the dealer however aftermarket (Rotary Aviation) kits run about $800-1000 in constrast to the almost $2000 price tag of a rebuild when going through a stealership. Time-wise they are very cost effective as the rebuild can be done in under an hour without breaking a sweat.

ooohhh, so all the rotarys I have removed and replaced really didnt blow up!! because on paper you say they are great engines! and $50 bucks for a rebuild!!! whaaaat!!!!! mabye for a oil pan gasket!!! the rx7 owners would be thrilled if parts only cost that much!!! any way Im not here to argue Im just saying AGAIN, that rotarys suck!!!!

Please, tell me how many you have R&R'd. I'm curious to know -- did you do the removals alone, or were you assisting another technician. Typically a dealership has a specified heavyline tech or in particular with Mazda dealers a 'Master Rotary Tech' who handles all drivetrain specific concerns of that magnitude. I'm also curious what the R&R time paid is on an RX-8. I know it can go upwards of 18hrs for an RX-7 (93-95). R&R time on the old FC's is less since its less 'PITA' work involved.

BTW, I just recently pulled my FD motor for a rebuild in my driveway, wasnt too bad, just an afternoon and a few snack/drink breaks.

the mazda tuning shop owners and techs next door to me would disagree with you. the engine is exotic so yes, parts are more expensive, and i have seen just as many chevy 350s, honda b18's etc... blow up. theyre not crappy engines if you know what youre doing, or else why would they still be making them.

Rotaries are more known to blowing a seal compared to those other motors but the reason is almost always due to miscare. Even in my situation I had a bad tune and ran lean at the top of 3rd. Proper warm up and cool down is a big deal in the FD's as is maintenance and a proper tune. If these things are kept in check its not impossible for a rotary to see 200k+. There are TWO FD's (The most trouble prone of the rotaries) that are well above 150k on their ORIGINAL motors from the factory.

~Kris

[mmm240]

anyone else for dumber having watched that vid

[s13rb25det]

o.k mr dopefish, here are the answers to your questions no, I do not own a rotary powered vehicle why would I be hammering on them if I owned one! yes I am a ASE tech in most fields of a car I have been out of the ford ASSET 2 year training program for about a year now. I do some of the engine R+R my self but mostly with another tech. we do not rebuild any engines at my dealership we just black box them! and yes, dealerships are very expensive! now to the reliability of the rotary motor, do people purchase rx8 and rx7 to pamper them? NO they go out and drive them like crazy!!! almost any other non turbod car should be able to handle this kind of driving but the rx8 does noT!!! believe me I see them all the time!! but hear me out on this, the wankel rotary does have hope and it WILL get better! think of it this way, when was the first rotary car mass produced? it was in the late 1970s. now when was the first piston engine mass produced? it was a 100+ years ago so the way I look at it the rotory is about 1940 technology! do you want to disagree about that!! every thing has to evolve! some day the rotary will be a great, well built, depenable engine, but for now it just makes me money!!!!!

[Dopefish]

o.k mr dopefish, here are the answers to your questions no, I do not own a rotary powered vehicle why would I be hammering on them if I owned one! yes I am a ASE tech in most fields of a car I have been out of the ford ASSET 2 year training program for about a year now. I do some of the engine R+R my self but mostly with another tech. we do not rebuild any engines at my dealership we just black box them! and yes, dealerships are very expensive! now to the reliability of the rotary motor, do people purchase rx8 and rx7 to pamper them? NO they go out and drive them like crazy!!! almost any other non turbod car should be able to handle this kind of driving but the rx8 does noT!!! believe me I see them all the time!! but hear me out on this, the wankel rotary does have hope and it WILL get better! think of it this way, when was the first rotary car mass produced? it was in the late 1970s. now when was the first piston engine mass produced? it was a 100+ years ago so the way I look at it the rotory is about 1940 technology! do you want to disagree about that!! every thing has to evolve! some day the rotary will be a great, well built, depenable engine, but for now it just makes me money!!!!!

Congrats on being ASE certified and completing the ASSET program.

I never said a rotary has to be pampered but it has to be well cared for. I wont argue that the rotary needs more attantion, thats what I even said. Tuning, maintenance and care is important. The engine must always be warmed up before getting on it and must be driven easy for a few minutes after driving hard. However, once its up to operating temperature a rotary will let you abuse it all day long in the high RPM's. Someone once told me that the RX-7 is like the Japanese Ferrari; it will take a lot of abuse and offer a lot of performance, but it will require a lot more attention and care than a normal car/engine.

I know I abused my car a lot in the time I've owned it. After disassembly I know why mine blew. Mostly it was my fault as my fuel filter was clogged and my tune wasnt appropriote for the modifications I had recently added. Privie to that I had been beating on my engine for over a year. This ofcourse while following maintenance and care. Piston engines will put up with a lot more but you cant tell me that a turbocharged/supercharged car will take being boosted when cold. Say goodbye to your piston rings with that one.

I will wholeheartedly agree that the rotary has a long way to go in developement but I disagree with your opinion that it sucks and is a worthless motor at this point in time. Given the fact I will be right at 330-340rwhp once my engine is complete, and thats with a little 1.3L rotary on the stock turbos running only slightly higher than stock boost (12PSI) I dont consider them worthless engines. Given another 60 years of developement we will see improvements, Mazda has made leaps and bounds of improvement over the years going from a mere 60bhp output to the now 239bhp N/A output of the Renisis. Due to the sideport design not only have emissions improved but the apex seal wear is greatly lowered as well so longevity with car should be improved by a fair bit.

I'll restate that the most common issue I've found people with RX-8's suffer from is carbon locked apex seals due to either being too easy on the car and allowing excessive buildup (Lots of soccermoms own these things) or getting in and driving it hard without allowing it to fully warmup thus warping the apex seals. I'm curious to know what the owners who have come in have treated their cars like or how well they were maintained -- or in some cases how 'lightly' they were driven on a day to day basis. I worked with a woman who bought an RX-8 and she drove it very easy, she let it warm up before going and such... she had the right mentality of care for the car but was inevitabily going to suffer from carbonlock eventually. I told her about how the rotary is and how it should be cared for so now every other day or so she will give it a good hard run near redline to assure that she doesnt collect too much carbon. She's owned the car for a little over a year now and has yet to suffer any issues.

~Kris

[s13rb25det]

yeah, I suppose the rotary really isnt that bad of an engine any more, its just not for me at this time! you could be very right about the carbon build up on the rx8. the climate in oregon is very cold and damp in the winter and could cause a concern on a rotary motor. Im not sure how all the owners of rx8s drive them or treat them, we have never bothered to tear a rotary apart to find the root cause, but this is the wierd thing about EVERY renisis rotory that was having hard starts, sputtering,slow acc, etc, every one had a knock sensor code, or miss fire code, mazda told us not to screw with it just pull it and ship it to them! so thats what we do! it seems like a waste to me! dopefish do you work at a dealership, or auto shop also? just wondering because you seem to know all the stuff about it! if you have any questions about the ASSET program or any other apprentice auto programs shoot me an email

[dickie]

i just recently had a fun experience at a ford/mazda dealership that confirmed what i suspected: there are no minimum requirements to be a tech or even a supervisor/manager at the dealerships, but they absolutely WILL NOT hire you if you are intelligent, helpful, or posess any basic motor skills at all...

[lee.]

i just recently had a fun experience at a ford/mazda dealership that confirmed what i suspected: there are no minimum requirements to be a tech or even a supervisor/manager at the dealerships, but they absolutely WILL NOT hire you if you are intelligent, helpful, or posess any basic motor skills at all...

Did you just pull that our of your ***? I have family that works in all parts of the big 3 in Michigan. To touch a car at any dealership you need to have a basic auto certification (like an ASE) then you must complete the manufacturer required training for a specific job title. Example, the front end alignment guy has over 18 months of training. Not only does he do the alignment he has to inspect the structural integrity of the frame/mounts and everything that connects to the frame from the suspension. That guy makes 85-125k a year depending on the dealership. The factories require the dealerships to have their tech's certified by them. Please don't ever spread false information again, you just make yourself look bad.

[Dopefish]

dopefish do you work at a dealership, or auto shop also? just wondering because you seem to know all the stuff about it! if you have any questions about the ASSET program or any other apprentice auto programs shoot me an email

I use to work for a Ford dealership in my area, left because the rednecks I worked with kept pissing me off. I'd consider a Mazda/Nissan dealer again but I'll never work for a domestic shop again unless its like Cadillac (Where my brother works) or some other luxury brand dealer. I went into ASSET straight out of high school, it was a good program but it started out VERY slow and VERY basic. In either case I'm kinda far from cars at the present moment I'm a network systems analyst.

EDIT: d!ck, I worked with some rednecks that pissed me off but even they were pretty capable with a wrench on occasion. However there were two or three techs there that impressed me and were above and beyond what you'd expect to find at a dealership, I imagine that the majority of them are quite capable and intelligent -- you may have a bad experiance with some dealers but most of the time the techs themselves are not the root of it.

~Kris

[dickie]

i can pass a test and take some courses and choose to be a lazy ******* and not apply any of the information should i choose to do so, like some people most obviously DO. please dont attempt to stand up for these ***holes that make the helpful and motivated guys (rare around these parts) look bad.

its a question of motivation overcoming laziness. Ford instituted a recall so youd think at least one of the several people that ford pays to know this kind of thing would be there... if not it would have taken at max 10 mins to find out and give us an answer, but since they obviously didnt give half a crap, they just blew us off. greaaat. i notice also that a lot of these guys will admit to not knowing anything beyond the EXTREME basics of the mazda cars that their dealership sells, and they will actually refer you to a mazda dealership hours away or a private shop that will perform warranty work... so wtf is up with that? nobody cares enough to try i guess.

[s13rb25det]

d!ck, I have no idea what you are talking about!! does anyone else feel stupider for reading his thread?!! dont even get me started!!! you sound like a WYOTECH guy anyway so I wouldnt expect more from ya!! hey dopefish did you finish your asset training, or was it just not your thing? I dont think I will make a career out of being a auto tech either! its just a hobby right now! I im looking in to real estate as a career very soon,

[dickie]

ya dude im sure you do feel stupider!!! and im not surprised you have no idea what im talking about!! WYOTECH is in Texas now?!! You do sound like a real estate guy so i wouldnt expect more from ya!!

[Kenrik]

ya dude im sure you do feel stupider!!! and im not surprised you have no idea what im talking about!! WYOTECH is in Texas now?!! You do sound like a real estate guy so i wouldnt expect more from ya!!

I for one feel a litle stupider 90% of the time I read d!ck posts... but hey we can keep him around 10% of the time he has something semi inteligent to say..

(like i'm one to talk LOL)

[s13rb25det]

why would I care were wyotech is? and have you worked at a auto shop for a decent amount of time? or is burger king your only job!!?? I have a 2 year degree in auto repair, a good paying job and I am working on a second degree in bussiness adm. what do you have? besides your great auto skills!!!!

[lee.]

I for one feel a litle stupider 90% of the time I read d!ck posts... but hey we can keep him around 10% of the time he has something semi inteligent to say..

(like i'm one to talk LOL)

I can tell the "stupidness" is taking an affect on you. Forgot your 2nd t on little and the 2nd l on intelligent. I don't know if it was intentional but, it only adds to the comedic goldmine here!