Rotary Magic

We may earn a small commission from affiliate links and paid advertisements. Terms

SlushboxTeggy

SlushboxTeggy

It's only stupid if it doesn't work
VIP
I assume most of us have little knowledge on rotaries and how they work. We just know that Mazda makes them and dark magic is involved in creating the power. Well I came across this video today that allowed me to visualize what actually happens and I figured I'd share.
YouTube - Rotary Engine
 
I still believe to this day that Rotary's have black magic in them to this day. But great find.
 
i still remember the first time i helped my friend open one of these up

:confused: wtf?? thats it?!?!

i love rotary engines

here is a nice animation of what is going on inside
wankel-rotary-engine.gif


the video is more accurate as far as where the actual intake and exhaust ports are
 
all i got from that video is that there are a lot of coolant jackets. i still don't get it.

and if they are that awesome, why doesn't everybody use it?
 
too much maintenance i guess? I know you have to change the apex seals after so many miles. compared to a standard 4 stroke engine doesn't require nothing more than the usual oil change and spark plugs so many miles.
 
Last edited:
basically think of them like a 2 stroke engine for a car

pros:
light weight
very good power in comparison to its size
simple design with only 3 moving pats
smooth low vibration operation

cons:
they are not known for their fuel efficiency
they use oil in the combustion process (oil levels require more attention from owners)
they are not "clean" emissions wise... thought he new Renisis is cleaner than the Wankel was
they do not have as log of a life span as a piston engine... and their lifespan is greatly reduced by owners who do not understand how to properly drive or maintain a rotary engine
no one knows how to work on them
rotary engines do not make a lot of torque... this does not match up well with todays bloated cars
 
i'm deathly afraid to buy an FD purely for those reason. the stupid things can easily be built to 500hp, but nobody wants to do it. there are a handful of builders in each city, and they are expensive.
 
The biggest problem ive seen with a high horsepower build on rotary engine build is apex seals failing. But at the same time its like you said super easy to get 500+ hp.
 
proper driving is important
allow them to warm up for 30-60 seconds before driving them
keep the RPMs under 3500 until they get to normal operating temperature
you need to bring the RPMs up from time to time... the oil injection is based on RPM... low RPM = not much oil getting into the mix = premature wear to the apex seals = :thumbsdown:
after driving it hard allow a few minutes of easy driving... or a minute or two for cool off before turning the car off

oil is a big discussion for rotary engines...
they like heavy oils... as per the owners manual... 20w50 is recommended above 16*F 10w40 above -9*F... and DO NOT use 10w30 above 86*F
mazda recommends staying away from synthetics because one of the ones in their tests caused a lot of wear promoting deposits when burned... instead of naming it they put out a blanket anti synthetic advisement... there was also issues with the O rings and seals used in older wankels... the renisis does not seem to have the same issues
several synthetic oils state that they are OK for use in rotaries ( Royal Purple FAQs )
there are also oils specifically designed for use in a rotary engine ( Idemitsu racing rotary engine oil and premix lubricants)
it is also not unheard of for people to do a light mix of premium ashless 2 stroke oil in their gas



best advise i can give anyone wanting to start doing shit to a rotary powered car...
learn spanish
im serious... just about every person i have ever seen with a fast rotary has been hispanic


other than that... TUNING
tuning is important as fuck... pre-detonation can destroy an apex seal QUICKLY... then your compression goes to shit and you get to rebuild an engine you dont understand



as with anything do a lot of research and you will save yourself a LOT of money and frustration in the end
 
E_SolSi said:
it is also not unheard of for people to do a light mix of premium ashless 2 stroke oil in their gas
Click to expand...

I was just about to say that I do know a guy with a FD that said he took out his oiler just because he's afraid of it failing and premixes 2 cycle oil in his fuel, along with a better flow fuel filter and whatever.
 
I'm more curious how they time these cars, like how can you adjust the timing? Does it have a crank position sensor?
 
I own one^_^..actually I own two, so many myths about rotaries, overall I think they're awesome engines, yes they require maintenance and by maintenance I mean regular maintenance, with piston engines you can kinda get away with neglecting your motor, with rotaries you can't. One thing that was mentioned before was fuel economy, something rotaries don't have. They're kind've a pig on gas and emissions tend to be a lot heavier, especially if you start tinkering. For this reason they never really became too popular, the world is driven towards a car that has great fuel economy and fewer emissions (All about the enviroment). As for the myth about rotaries always blowing up, it's only due to owner abuse and a lack of education. You can't just crank up the boost or expect to push 500 horse without any internal work, just like any other engine. This fact apparently gets overlooked many times when people build up their rx7, they expect to run 500hp with stock internals??? Just doesn't make sense. I have never had any major engine issues with any one of the three rx7's i've owned and all I've done is maintain them. Sure the odd coolant issue, or fuel/igntion issue, nothing a good backyard mechanic couldn't solve. They also don't burn oil, the oil they do use is very miniscule and is part of their start up system. (It injects a little bit of oil at the start to lube up all the seals) It isn't very often you have to add oil in between regular oil changes if at all. They do however have a short spark plug life, your lucky to get a year if that from your plugs, they just don't last.

Note: Esolsi ...how do they not have torque? stock s5 fc tii is somwhere around 205hp/195tq i believe.
 
yeah the turbo charged ones do make nice power
i was thinking of the NA ones that i have spent more time around

the first gens (my personal favorite) with the 12A put out 101hp/107tq... the GSL-SE model had a fuel injected 13B and put out 135hp/133tq

the second gens all had versions of the 13B NA models put out 146hp/138tq
s4 turboII models put out 182hp/183tq
s5 turboII models put out 200hp/196tq

the third gens (that we got here) all had the same twin turbo setup making 255hp/217tq

so yes when paired with a turbo they do make torque
 
Even after all the knowledge gained, if I picked up a RX-7, the first mod would be an LS1.
 
E_SolSi said:
yeah the turbo charged ones do make nice power
i was thinking of the NA ones that i have spent more time around

the first gens (my personal favorite) with the 12A put out 101hp/107tq... the GSL-SE model had a fuel injected 13B and put out 135hp/133tq

the second gens all had versions of the 13B NA models put out 146hp/138tq
s4 turboII models put out 182hp/183tq
s5 turboII models put out 200hp/196tq

the third gens (that we got here) all had the same twin turbo setup making 255hp/217tq

so yes when paired with a turbo they do make torque
Click to expand...

So with that being said they make decent power and torque in N/A form. D-series VTEC motors make what 127hp and around 100 lb/ft of tourque?
 
and i would not call a D series torquey either
i also wouldnt call a B series torquey
i would only call an H series torquey when comparing it to other honda engines

a turbo does change things quite a bit... but in NA form they tend to be more high strung
 
You must log in or register to reply here.
Back
Top