I want an adult debate here. I just want to know the pros and cons of each, and what you think of them.

 

a rotary is more balanced, so its more free reving.
you get smaller displatement engines with greater HP

 

rotary has less moving mechanisms so less things to fail...because it operates some what like a 2 stroke motor using the rotor to open and close the port...u can make tremendous power from a porting job....its design leads to smoothe power building accross the redline

for some reason rotarys tend to like using lots of fuel, and like to get really hot......especially the exhaust..

 

id have to go with rotary. the 13b only has three moving parts. and one rotor actually acts like three pistons in one. so an engine with two rotors(13b) is almost like a six piston engine. but id have to go with radial engines myself. they are pimp!!!!!!!

 

rotary and reed kart engines are quicker than the piston ports. so id go for a rotary everytime.
is someones thinking of getting a RX-7/8 then??

 

Just though I would let you know the Rotary Kart engine and a reed valve Kart Engine is still a piston engine. The Rotary in a car is completely different that what you are talking about.

 

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

You need to do more research before you ask broad questions like this.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kpt4321 &raquo;</TD></TR><TR><TD CLASS="quote">You need to do more research before you ask broad questions like this.</TD></TR></TABLE>

Agreed, knowing the specifics of each should give you the insight to see the benefits/downfalls of each.

 

I hate the fact that rotaries are SOOO sensitive to pinging compared to pistons motors, they are entirely too loud when trying to make power NA, eat fuel like there is no tomorrow, and always seem to be in desperate need of cooling like a polar bear with a fever in Thailand. Plus their exhaust is so freaking hot...wtf.

Put it this way; if 25 auto manufacturers have rights to produce Wankel motors, why has only one done anything with it? Could it be they are too reliable, less parts to break meaning less service down the road and less $ for the OE after the inital sale? Rotary freaks might say this, but I say it's cuz pistons motors are just better overall in many aspects; less hassle.

I want to say they are too peaky, especially without a turbo, but then again I drive a honda...




Modified by builthatch at 9:50 PM 1/15/2004

 

Rotary engines are "known" to use a lot of fuel and oil. The 12A & 13B motors are really "sensitive" meaning they need "care" if you wanna put it that way...

I've had RX-7 with the 12A and 13B motors and they are really happy when reved' high. They love porting jobs... huge power can be achieved thru this .
On the other hand the apex seals(oem) tend to not last long(my experiences) meaning when going high performance... so you'll definitely have to go with aftermarket seals(3mm). But the gains with this motor plus boost... FUN!!!

Piston engines are really good, realible and make power... They put great numbers but money wise I think rotaries are cheaper... If I had to choose I'll still go with a piston(B18C5) engine.. even though I love the rotaries... They are just to temperamental!!!(?)

 

well it depends on how u look at it...piston engines are more economical..probably better gas milages out of them too..

but i think performance wise rotarys are great especially in all motor format...maybe the wont make the same power a 5.0 liter piston engine with a t88 turbo...but i prefer them because of their simplicity

 

this is a great post. ok, i have built up V8s and a rotary, and now im workin on Hondas. my rx-7 i will not drive for a long time b/c it is far too fast. a stock rotary engine will not guzzle gas or be too loud or need massive amounts of care (except oil checks, this is b/c oil and gasoline have no choice but to mix in the rotor housings, and oil is burned as a result) however, along comes the need for power and it gets annoying at times. first, the tools to open the rotary a little out of the ordinary, the flywheel bolt needing if i remember correclty a 22 1/8 wrench and so on. if u replace the apex seals, ur gonna have a lot less worries, cuz stock ones quite plainly suck ***. now, the engine theory on rotary is that it ll go as fast as the amount of fuel that is put into it, thus its high revving capabilites. "bridging" or porting the intake and exhaust is where you really start losing fuel economy, in fact, to cruise, u usually end up sitting on ur clutch pedal cuz the rotary will insist on having more gas in a gear to make it happy. spark plugs pretty much will need to be changed every month, and they tend to be expensive for the 7's. when a header and exhaust are added, things get OBSCENELY loud! i let someone drive my car once and i heard it from (im serious) an estimated mile or so away. my neighbors still hate me and cops didn t like that, or the nitrous system. i have tickets to prove it! the heating/cooling is a bitch. plain and simple. actually my radiator never let the car run too hot, but in summer there was a noticeable lag in power due to the hot air. what sucked in my car (im sorry the motor is a 13B in an 84 mazda targa 7, i forgot to mention) was waiting for it to warm up. i had taken the fuel injection off and put on a holley carb to maximise fuel sending and atomization. i had to wait about 7 minutes everytime i wanted to take her out so the car would warm up to 180 degrees or id damage some ****, or she d stall. but she is fast! ive raced so many cars and won...even turbo ones! its not a matter of which is better, its a matter of how much u wish to deal with...

 

wankel=smaller, simpler design, but it's still in the infantcy imho
only one company is serious enough to invest moola into the rotaray.
the engine compartment is very very very little and very compact, the rotor off the older 7's can be held with a finger or two, the peanut shell housing can be put in some jansport backpack for those never work with rotary before, I am very surpise how's that little sucker get all the power.

like most of the comment above, rotary runs on gas and motor oil

I dont even own a wankel, what do i know..ha

 

whats more balanced, a piston or a rotary?

I would think a rotory is more balanced because it is lighter and smaller, there for making it easy to move back into the car allowing better wieght distrobution. But i love pistons more. ^_^

 

Rotaries are given about one hundredth of the development time that piston enges are given. You have no idea how well they would work if they had the sheer amount of people working with them that piston motors do.

Piston motors have like, billions of engineers working on them a year. The wankel in the RX-8 was set up by three guys in a closet.

I'd love to see one with real development.

 

i totally agree the rotary has about 50 years while the piston has about 120 years. The rotary has abot a 1/3 of the parts while one rotor makes 3 power strokes every 360 rotation.

Very nice motor had a 12a bridgeport, crazy sounds...

 

is sad to know that one of the reasons why rotaries are not populars is because piston engines are more prone to last longer (especially because of the extensive R&D they had over the last century), but get this right, the only reason rotaries are soo hated is because they require a lot of TLC and only the true enthusiast like to give TLC to a car.

They make tons of power, they eat gas, they are poorly developed but they have TONS of potential.

IMHO, i like 4 strokes, 2 strokes and rotaries, because each one has it's pros and cons....

BTW: what does TLC stands for?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GZERO &raquo;</TD></TR><TR><TD CLASS="quote">BTW: what does TLC stands for?</TD></TR></TABLE>

Tender love and care.

I agree though, rotaries haven't had a fraction of the research and development that conventional piston engine have had. Assuming someone would put some serious R+D into them then they have great potential.

 

honestly, a stock rx-7 can last a verrrryy long time, my buddy has an 84 as well with 368,000 miles and it still runs like new. The RX-8 is just a small testemonial as to what the rotary is capable of with some mods. side ports on the intermediate housing was a great idea. now, the stock motor makes as much hp as a twin turbo rx-7