Notices
Series I Tech Garage The place to discuss anything technical about the RX-8 that doesn't fit into any of the categories below.

rotary engines: advantages

Thread Tools
 
Rate Thread
 
Old Jan 7, 2008 | 06:12 PM
  #1  
TrochoidMagic's Avatar
Thread Starter
is adjusting valve lash
 
Joined: Sep 2007
Posts: 1,060
Likes: 0
From: hollywooood!
rotary engines: advantages

i'm wondering why i never saw a comparison of advantages of rotaries to pistons?
are they that obvious, or people just love it sooo much that they don't care?
at any rate, this will be some good read and leaves room for some more input.
PROS:
1)no timing belt to change
2)no sudden catastrophic failure from snapped belt compared to a timing belt equipped piston motor
3)less moving parts
4)no valve adjustment or other attached maintenance than regular routing maintenance
5)light weight

cons:
1)high oil consumption
2)high fuel consumption
3)more frequent ignition component maintenance
4)

please feel free to add. i'd like to see where the list stops.

and someone should sticky this, i'm tires of noobs coming in with "rx-8 vs S2k, which should i get?" posts. let them see the pros/cons for themselves

Last edited by TrochoidMagic; Jan 7, 2008 at 07:25 PM.
Reply
Old Jan 7, 2008 | 06:21 PM
  #2  
dillsrotary's Avatar
jersey fresh
 
Joined: Dec 2005
Posts: 3,688
Likes: 0
From: Boston, MA
Originally Posted by TrochoidMagic
i'm wondering why i never saw a comparison of advantages of rotaries to pistons?
Reply
Old Jan 7, 2008 | 06:33 PM
  #3  
DarkBrew's Avatar
Extraordinary Engineering
 
Joined: Oct 2005
Posts: 4,733
Likes: 14
From: Burls On
Reply
Old Jan 7, 2008 | 06:34 PM
  #4  
chetrickerman's Avatar
Banned
 
Joined: Sep 2007
Posts: 2,643
Likes: 0
From: Waukesha Wisconsin
where do you get that popcorn, i cant find it in the smileys
Reply
Old Jan 7, 2008 | 06:36 PM
  #5  
Crztrtldck's Avatar
Jonathan
 
Joined: Jun 2007
Posts: 200
Likes: 0
From: Houston
Pro:
longer torque band.

its not a massive amount of torque but theres a longer band along the revs

another Pro: high revving
Reply
Old Jan 7, 2008 | 06:37 PM
  #6  
nycgps's Avatar
Out of NYC
iTrader: (1)
 
Joined: Jun 2005
Posts: 19,881
Likes: 36
From: Planet Earth
Originally Posted by TrochoidMagic
3)more frequent ignition component maintenance
Are you talking about our spark plugs ?
Reply
Old Jan 7, 2008 | 07:07 PM
  #7  
DarkBrew's Avatar
Extraordinary Engineering
 
Joined: Oct 2005
Posts: 4,733
Likes: 14
From: Burls On
Originally Posted by chetrickerman
where do you get that popcorn, i cant find it in the smileys
http://i34.photobucket.com/albums/d1...ad/popcorn.gif
Reply
Old Jan 7, 2008 | 07:15 PM
  #8  
chetrickerman's Avatar
Banned
 
Joined: Sep 2007
Posts: 2,643
Likes: 0
From: Waukesha Wisconsin
thanks
Reply
Old Jan 7, 2008 | 07:20 PM
  #9  
TrochoidMagic's Avatar
Thread Starter
is adjusting valve lash
 
Joined: Sep 2007
Posts: 1,060
Likes: 0
From: hollywooood!
Originally Posted by nycgps
Are you talking about our spark plugs ?
yes. but it wouldn't only be that now.
Reply
Old Jan 7, 2008 | 07:24 PM
  #10  
TrochoidMagic's Avatar
Thread Starter
is adjusting valve lash
 
Joined: Sep 2007
Posts: 1,060
Likes: 0
From: hollywooood!
Originally Posted by Crztrtldck
Pro:
longer torque band.

its not a massive amount of torque but theres a longer band along the revs

another Pro: high revving
doesn't seem to be a highlighted point or boasted about often. but o well...its still impressive for its given size.

high revving...yes, that one is good.
Reply
Old Jan 7, 2008 | 07:31 PM
  #11  
TrochoidMagic's Avatar
Thread Starter
is adjusting valve lash
 
Joined: Sep 2007
Posts: 1,060
Likes: 0
From: hollywooood!
Originally Posted by dillsrotary
what? you can't gather any thoughts?

pros and cons.

supply them. whats it to you?

have you seen the constant lame questions of car comparisons posts by noobs?

i'd have to agree that rotaries are NOT for everyone. and if you are clear on the pros/cons of it, then make your decision on such...its like no-one bothers to get a friggin brochure nowadays.

so yeah, any pros/cons you'd like to supply?
Reply
Old Jan 7, 2008 | 07:32 PM
  #12  
mysql101's Avatar
⎝⏠⏝⏠⎠
 
Joined: Apr 2004
Posts: 8,625
Likes: 5
From: USA
pro: high exhaust flow and temperatures!
Reply
Old Jan 7, 2008 | 07:38 PM
  #13  
TrochoidMagic's Avatar
Thread Starter
is adjusting valve lash
 
Joined: Sep 2007
Posts: 1,060
Likes: 0
From: hollywooood!
just how is that a pro? with all seriousness...

i know one power stroke/exhaust stroke every crank revs. or 3 crank rev for every one rotor revolution... but what are the exact advantage of having high temps?

and is that what you would like to state as an advantage if you were promoting the facts of this motor?
Reply
Old Jan 7, 2008 | 07:43 PM
  #14  
chetrickerman's Avatar
Banned
 
Joined: Sep 2007
Posts: 2,643
Likes: 0
From: Waukesha Wisconsin
it enables for a small engine like the 1.3L renesis to use a reasonably large turbo with basically no lag time
Reply
Old Jan 7, 2008 | 07:45 PM
  #15  
TrochoidMagic's Avatar
Thread Starter
is adjusting valve lash
 
Joined: Sep 2007
Posts: 1,060
Likes: 0
From: hollywooood!
i see. that must've blew right by me. thanks.
Reply
Old Jan 7, 2008 | 07:49 PM
  #16  
TrochoidMagic's Avatar
Thread Starter
is adjusting valve lash
 
Joined: Sep 2007
Posts: 1,060
Likes: 0
From: hollywooood!
Originally Posted by TrochoidMagic
i'm wondering why i never saw a comparison of advantages of rotaries to pistons?
are they that obvious, or people just love it sooo much that they don't care?
at any rate, this will be some good read and leaves room for some more input.
PROS:
1)no timing belt to change
2)no sudden catastrophic failure from snapped belt compared to a timing belt equipped piston motor
3)less moving parts
4)no valve adjustment or other attached maintenance than regular routing maintenance
5)light weight
6)high exhaust flow: turbocharge friendly
7)compact size for lower placement and pmoi
cons:
1)high oil consumption
2)high fuel consumption
3)more frequent ignition component maintenance
4)

please feel free to add. i'd like to see where the list stops.

and someone should sticky this, i'm tires of noobs coming in with "rx-8 vs S2k, which should i get?" posts. let them see the pros/cons for themselves
....
Reply
Old Jan 7, 2008 | 08:52 PM
  #17  
enforcer's Avatar
Registered User
 
Joined: Nov 2006
Posts: 1,432
Likes: 0
From: Brisbane
+ 1 (Thanks Darkbrew...!)
Reply
Old Jan 7, 2008 | 09:00 PM
  #18  
heyarnold69's Avatar
Rotary wanabee
iTrader: (1)
 
Joined: Jul 2007
Posts: 1,978
Likes: 0
From: Long Island, NY
pro ---- small. adn takign out one involves 2 people and a small wrench.

no seriously. thats it ......... no wenches, etc..
Reply
Old Jan 7, 2008 | 09:11 PM
  #19  
Socket7's Avatar
ಠ_ಠ
 
Joined: Aug 2007
Posts: 2,228
Likes: 6
From: Under the Dumbarton Bridge
Gives you an excuse to say wankle in polite company.
Reply
Old Jan 7, 2008 | 10:00 PM
  #20  
MazdaManiac's Avatar
Banned
iTrader: (3)
 
Joined: Oct 2003
Posts: 16,386
Likes: 28
From: Under my car
Pro: It goes "Hmmmmm"
Pro: It doesn't go "BOING BOING BOING"

Reply
Old Jan 7, 2008 | 10:41 PM
  #21  
New Yorker's Avatar
Registered
 
Joined: Sep 2003
Posts: 3,319
Likes: 58
From: NYC
Hmm, should I have an engine with over a thousand moving parts—or three? Gee, that's a tough one.

The big advantage of the rotary is… feel & handling. The tiny, lightweight Renesis–barely 13" tall—allows a near mid-engine design and a 50/50 weight balance—the secret behind the 8's remarkably lively feel, agility and handling.
Reply
Old Jan 8, 2008 | 12:42 AM
  #22  
TrochoidMagic's Avatar
Thread Starter
is adjusting valve lash
 
Joined: Sep 2007
Posts: 1,060
Likes: 0
From: hollywooood!
yes, and contributing to a lower yaw and pmoi. i added that in there already. you just said it better. but thanks anyway.
Reply
Old Jan 8, 2008 | 01:11 AM
  #23  
daisuke's Avatar
rotorized!!!
 
Joined: Feb 2006
Posts: 653
Likes: 0
From: San Luis Obispo, CA
the biggest pro for the rotary isn't for cars, it's for airplanes:

reliability thru simplicity: it won't fail catasthophically because it's perfectly balanced. Even if it blows a seal or it misfires or the oil runs out, if you have a problem the engine will still make some form of power for an amount of time, enough to get you that little extra distance and quite possibly save your life.

A piston engine that throws connecting rod or something of the like will literally tear itself to pieces, immediately lose all power and depending on the damage even eject pistons or other parts out the side of the aircraft.

it's also quieter and the frontal profile is much much smaller that lets you design more aerodynamically.

but there are still tradeoffs, you need to water cool it and you need a gearbox to get the engine revs down to normal prop operating speeds so the weight advantage doesn't exist.
Reply
Old Jan 8, 2008 | 01:24 AM
  #24  
TrochoidMagic's Avatar
Thread Starter
is adjusting valve lash
 
Joined: Sep 2007
Posts: 1,060
Likes: 0
From: hollywooood!
interesting newfound information... cool stuff. i can see the other advantages of rotaries being in aairplanes.
Reply
Old Jan 8, 2008 | 01:35 AM
  #25  
paulmasoner's Avatar
Asshole for hire
iTrader: (1)
 
Joined: Jun 2006
Posts: 3,214
Likes: 3
From: Colfontaine, Belgium
Originally Posted by MazdaManiac
Pro: It goes "Hmmmmm"
Pro: It doesn't go "BOING BOING BOING"

am i the ONLY one who read more out of this then just the words?
Reply


You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -5. The time now is 05:11 PM.