Page 1 of 2 12 LastLast
Results 1 to 40 of 41

Thread: Rotary Engines

  1. #1
    RC poster
    Join Date
    Oct 2006
    Location
    Joplin Missouri
    Posts
    13

    Question Rotary Engines

    Anybody into rotary engines or own a rotary engined car, even a mazda.
    7's ONLY

  2. #2
    RC Turnbuckle Jr.
    Join Date
    Sep 2006
    Location
    Marietta, OH
    Posts
    3,073
    my neighbor has an 1988 RX-7 converable in excellant condition. its got a rotary.

  3. #3
    RC Champion
    Join Date
    Jul 2006
    Location
    Look out your window...
    Posts
    1,144
    Rotary's are cool engine designs. We actually got to rebuild one in Tech School about 10 years ago.

    http://auto.howstuffworks.com/rotary-engine.htm<<some of the best pictures and info on them around.
    No he's not the Tom from M-Space!

  4. #4
    RC poster
    Join Date
    Oct 2006
    Location
    Joplin Missouri
    Posts
    13
    there fast, make great power and especcially easy to rebuild. my grandpa owns a 1200cc
    12A rotary engine that makes 300hp no turbos. peak power around 10,500rpm. i've seen him and my uncle pick the engine up right out of the 1995 RX-7 he owns. A RE powered R/C car is a thought.
    Last edited by SLEDGE_74; 11-09-2006 at 07:29 PM.
    7's ONLY

  5. #5
    RC poster
    Join Date
    Oct 2006
    Location
    Bear, Delaware
    Posts
    18
    13Bs and 20Bs are nice motors when mated with a good turbo, but they will blow up like no other. 13Bs also eat apex seals for lunch

  6. #6
    RC poster
    Join Date
    Oct 2006
    Location
    Joplin Missouri
    Posts
    13
    Quote Originally Posted by MaxxkillaV2
    13Bs and 20Bs are nice motors when mated with a good turbo, but they will blow up like no other. 13Bs also eat apex seals for lunch
    Depends on which apex seals you use. Stock steel seals are not guarenteed above 8000rpm. on the other hand carbon seals are rated to 9500rpm but not very long. Then the ceramic seals are rated to 12,000rpm, and any rotary motor with ceramic seals if you can keep your motor under 10,000rpm every race it probably would last forever. my grandpa's
    12A has revved 16,500rpm missing a shift for 4-gear to 1-gear, going 120mph, and it only put a scratch in a rotor bearing.
    but ceramic seals cant handle nitrous, and are around $3000 bucks for a set of seals.
    Last edited by SLEDGE_74; 11-10-2006 at 07:06 AM.
    7's ONLY

  7. #7
    Registered User
    Join Date
    Oct 2006
    Posts
    691
    i like the rotary r/c engine idea myself. if only it would get better milege.

    has anyone hear of the mazda 787b race car? it is a really good one and runes off of a rotary 4 engine and it was the la mans champion the last year it raced.
    note: that mazda's engine sounds like it's going to fall apart yet that is just the way it sounds.
    Last edited by Traxxasfan24; 11-10-2006 at 07:21 AM.

  8. #8
    RC Champion
    Join Date
    Oct 2006
    Location
    Jacksonville Florida
    Posts
    1,441
    Quote Originally Posted by SLEDGE_74
    my grandpa's
    12A has revved 16,500rpm missing a shift for 4-gear to 1-gear, going 120mph, and it only put a scratch in a rotor bearing.
    whoa geez! ha try that with ur 4 cycle.....

    boom maybe?

  9. #9
    RC Turnbuckle Jr.
    Join Date
    Apr 2006
    Location
    Lincoln, NE
    Posts
    5,257
    I love the concept of the RE engines. They produce great power and are actually very easy to work on. But don't get me wrong, I love my big ol V8s.
    My truck sees more air than yours!!!

  10. #10
    RC poster
    Join Date
    Oct 2006
    Location
    Joplin Missouri
    Posts
    13
    the 787b had 690hp and weighted 2000lbs. it was fast.

    the rotary rc car idea would be cool. BUT the downside would be you couldn't use nitro fuel. it would be very fast and easy to start having low compression.
    the exhaust would melt parts

    the reason rotary engines are better than regular combustion engines is because you don't have valves or pushrods. There's no valvetrain. in other words if you racing somebody hard into a corner the other guy with his 4 banger or whatever it may be has to shift but you don't not having a valvetrain. not having to worry about bending valves or pushrods.

    thanks 1fast3.3 for that link. i haven't seen that before.
    7's ONLY

  11. #11
    RC Turnbuckle Jr. Highlanduh's Avatar
    Join Date
    Apr 2003
    Location
    Rhode Island
    Posts
    3,431
    Quote Originally Posted by SLEDGE_74
    There's no valvetrain. in other words if you racing somebody hard into a corner the other guy with his 4 banger or whatever it may be has to shift but you don't not having a valvetrain. not having to worry about bending valves or pushrods.
    Please elaborate on exactly how the lack of a valvetrain means you don't have to shift.
    Don't believe everything you think.

  12. #12
    RC poster
    Join Date
    Oct 2006
    Location
    Joplin Missouri
    Posts
    13
    theres nothing to break overreving the engine besides the seals. but it doesn't hurt the engine doing it once or twice in one race because you cant bend valves or pushrods. it just wears out seals.
    also depends on which seals you have and which engine you running.
    Last edited by SLEDGE_74; 11-10-2006 at 08:20 PM.
    7's ONLY

  13. #13
    RC poster
    Join Date
    Oct 2006
    Location
    Bear, Delaware
    Posts
    18
    Quote Originally Posted by Highlanduh
    Please elaborate on exactly how the lack of a valvetrain means you don't have to shift.
    Dont think he meant shifting, but if you over-rev 4 stroke motors you could get valve float, and thats what bends valves.

    whoa geez! ha try that with ur 4 cycle.....

    boom maybe?
    16,500 can be done with 4 cycle motors. You seen the redline on the new R6? We're talkin 16k-17K rpms.

  14. #14
    RC Turnbuckle Jr.
    Join Date
    Sep 2006
    Location
    Marietta, OH
    Posts
    3,073
    formula one car engines make way more rpm than a rotary, they can easily hit 19,000.
    Last edited by aussiek2000; 11-11-2006 at 03:47 PM.

  15. #15
    RC Champion
    Join Date
    Jan 2005
    Location
    Colorado
    Posts
    1,247
    Heck - you want impressive, look at top fuelers. They do 9500rpm with a 500 cubic inch V8. That is incredible, considering the size of the pistons...

  16. #16
    Marshal BobR's Avatar
    Join Date
    Apr 2001
    Location
    Asheville, NC
    Posts
    5,087
    Quote Originally Posted by SLEDGE_74
    theres nothing to break overreving the engine besides the seals. but it doesn't hurt the engine doing it once or twice in one race because you cant bend valves or pushrods.
    Engine wear is cumulative... your logic isn't quite sound in that respect.
    Six in a row makes it go.

  17. #17
    RC Qualifier
    Join Date
    Aug 2006
    Location
    Louisiana
    Posts
    764
    Rotary engines aren't bad, but there is a reason they don't use them very much. They just don't win that many races.

  18. #18
    RC Turnbuckle Jr. Highlanduh's Avatar
    Join Date
    Apr 2003
    Location
    Rhode Island
    Posts
    3,431
    Quote Originally Posted by MaxxkillaV2
    Dont think he meant shifting
    OK, but I can't imagine what else he could possibly mean by this:

    ... the other guy with his 4 banger ... has to shift but you don't ...

    And after I asked him to elaborate, he tried to, so apparently he thinks that's what he meant..
    Last edited by Highlanduh; 11-11-2006 at 08:17 PM.
    Don't believe everything you think.

  19. #19
    RC poster
    Join Date
    Oct 2006
    Location
    Joplin Missouri
    Posts
    13
    you have to consider that formula one cars. have way more money into them than anybody who has ever put into a rotary engine before.
    you also have to understand that overreving a rotary engine is not a problem if the engine is properly balanced and lightened. the real problem is nobody has the technology the make the seals last over 12,000 rpm. also not enough oil is supplied to the rotor bearings unless you have factory dry sump. which is very expensive in which not many people have. and most of the SCCA, le mans, and NASA classes restrict rotarys because they are so fast. once unrestricted, if you stick a big enough of a carberetor onto a periphial ported rotary motor, no matter what size rotary it is they can produce MASSIVE amounts of power at high rpm. although not reving as high as formula one car. it still revs qiuck. take a look at this pic. below so i can explain the diff. between a periphial motor and a stock ported motor.

    in the picture the large ports or the round ports are the periphial ports and the smaller ports beside them are the stock ports. they block the stock ports off with epoxy when using the periphial ported housings. and when using the periphial housing you produce more power because there is nothing restricting the air and fuel flow going to the rotors. the intake manifold is a aluminum tube. that is bent at a 90 degree curve. allowing massive amounts of fuel and air to pass through the engine but, nobody allows people to use big enough carbs on them to produce and use all of your power.
    the stock ports flow fuel diagnoly through the intermediate housings. some of this info. is in the how stuff works link
    1fast3.3 sent.
    i am sorry if i can't explain this very well. i know alot about the rotary engine. but sometimes i can't put some of the info into words. i wish i had a better vocabulary.
    Last edited by SLEDGE_74; 11-11-2006 at 08:26 PM.
    7's ONLY

  20. #20
    RC Racer
    Join Date
    Mar 2005
    Location
    NEPA
    Posts
    114
    Its a shame chevy sold the rights to the rotary engine. Just imagine how popular the Vega would have been.



    Or how about the Corvette with a Wankel...




    Four rotor Vette

    Last edited by CDR-M@X; 11-11-2006 at 10:18 PM.
    $$ I have too many hobbies $$

  21. #21
    RC Champion
    Join Date
    Oct 2006
    Location
    Jacksonville Florida
    Posts
    1,441
    Quote Originally Posted by MaxxkillaV2

    16,500 can be done with 4 cycle motors. You seen the redline on the new R6? We're talkin 16k-17K rpms.
    i know that. i said "ur" 4 cycle. doubt many people on this board have something like that.

  22. #22
    RC Qualifier
    Join Date
    Jul 2006
    Location
    Hawaii
    Posts
    303
    There was a .30 Wankle made by OS, but I cant seem to find it.

    It was originally made for airplanes, but I saw in RCCA that some guy managed to put it in a USA-1. He seemed pleased with the results, but that was before the days of the T-Maxx style monster trucks.

  23. #23
    RC poster
    Join Date
    Oct 2006
    Location
    Joplin Missouri
    Posts
    13
    Quote Originally Posted by aznfro
    There was a .30 Wankle made by OS, but I cant seem to find it.

    It was originally made for airplanes, but I saw in RCCA that some guy managed to put it in a USA-1. He seemed pleased with the results, but that was before the days of the T-Maxx style monster trucks.
    if you ever do find it send me a link.
    7's ONLY

  24. #24
    RC Turnbuckle Jr.
    Join Date
    Jan 2006
    Location
    SoCal
    Posts
    3,930
    The 787B is insane...it has like 3 or 4 rotors... an RX has 1 rotor lol...

    As for rotary engines, they are awesome, but they are only as good as the seals are. You need good apex seals or else say buh-bye when you over-rev it. I'm not all that big of a rotary fan though...

    As for normal 4-Stroke Piston motors...they can rev very high. The BMW M5 has a 5L V10 that rev's to 8,250RPM. My dad's 2004 Yamaha R1 rev's to 13,750. My Brother's 06 Yamaha R6 can do 17,500 with a race chip (he's going to get it later).

    And lastly, a 2.4L V8 from a Formula 1 Car can do 20,000RPM's. The rev limiter is set at 20,001. I have seen a dyno before... they happen to idle at 9,000 RPM too.

    I am personally a fan of high-revving naturally aspirated engines. Turbo's create a concentrated powerband that makes a car really annoying to drive...

    My brother's EVO 8 has like 450hp but it annoying to drive cause you have to run it in the Turbo's range or it kind of bogs. And its really loud in the turbo range. Don't get me wrong its really fast, but it makes it a not-so-friendly daily driver, since you have to shift all the time to keep the RPM's up (his turbo range is like 2,900-7,500, with the redline at 8,000).
    BP stands for Brushless Powered - LMT1940/7 CF G2R

  25. #25
    RC Turnbuckle Jr.
    Join Date
    Jan 2006
    Location
    SoCal
    Posts
    3,930
    Here is the F1 Dyno Video. The Revlimiter is set at 20,003 no 20,001 sorry.

    Also, here is a pretty cool video of My Country is to me "played" by an F1 engine.
    BP stands for Brushless Powered - LMT1940/7 CF G2R

  26. #26
    Registered User
    Join Date
    Oct 2006
    Posts
    691
    Quote Originally Posted by BP-Revo
    The 787B is insane...it has like 3 or 4 rotors... an RX has 1 rotor lol....
    it had a 4 rotor engine and if you put a turbo on it it will have around 800hp i think. that is if you can find room on the engine to put a turbo lol.

    Quote Originally Posted by BP-Revo
    And lastly, a 2.4L V8 from a Formula 1 Car can do 20,000RPM's.
    a lot of f1 cars run v10's in them and thay had 886hp a year ago.

    Quote Originally Posted by BP-Revo
    The rev limiter is set at 20,001. I have seen a dyno before... they happen to idle at 9,000 RPM too.
    yea but the f1 engines are 6 stroke i think.

  27. #27
    RC poster
    Join Date
    Oct 2006
    Location
    Joplin Missouri
    Posts
    13
    Quote Originally Posted by BP-Revo
    The 787B is insane...it has like 3 or 4 rotors... an RX has 1 rotor lol...

    As for rotary engines, they are awesome, but they are only as good as the seals are. You need good apex seals or else say buh-bye when you over-rev it. I'm not all that big of a rotary fan though...

    As for normal 4-Stroke Piston motors...they can rev very high. The BMW M5 has a 5L V10 that rev's to 8,250RPM. My dad's 2004 Yamaha R1 rev's to 13,750. My Brother's 06 Yamaha R6 can do 17,500 with a race chip (he's going to get it later).

    And lastly, a 2.4L V8 from a Formula 1 Car can do 20,000RPM's. The rev limiter is set at 20,001. I have seen a dyno before... they happen to idle at 9,000 RPM too.

    I am personally a fan of high-revving naturally aspirated engines. Turbo's create a concentrated powerband that makes a car really annoying to drive...

    My brother's EVO 8 has like 450hp but it annoying to drive cause you have to run it in the Turbo's range or it kind of bogs. And its really loud in the turbo range. Don't get me wrong its really fast, but it makes it a not-so-friendly daily driver, since you have to shift all the time to keep the RPM's up (his turbo range is like 2,900-7,500, with the redline at 8,000).
    the mazda rx-2, rx-3, rx-4, and rx-7 all had and 2 rotor rotary engine but all had different sizes. the 787B had a 2.6 liter 4 rotor.
    7's ONLY

  28. #28
    RC Turnbuckle Jr.
    Join Date
    Jan 2006
    Location
    SoCal
    Posts
    3,930
    Quote Originally Posted by Traxxasfan24
    a lot of f1 cars run v10's in them and thay had 886hp a year ago.
    That is somewhat correct.

    All the way up to the 2004-2005 season, they had 3.0L V10's. However, they produced over 1500hp. The new 2.4L V8's were commissioned and put into effect last year (2005-2006 season) and still have 1300hp, but alot less torque.

    The F1 Regulations did this because Kimi Raikkonen's McLaren Mercedes (with the V10) was hitting over 240mph on the straights of certain tracks, and a crash at that speed would be disasterous.

    So, now, they have the V8's which hit about 200mph.

    yea but the f1 engines are 6 stroke i think.
    No...they are 4 stroke lol
    BP stands for Brushless Powered - LMT1940/7 CF G2R

  29. #29
    RC Qualifier
    Join Date
    Jul 2006
    Location
    Hawaii
    Posts
    303
    Can anyone explain to me a 6 stroke?

  30. #30
    Marshal BobR's Avatar
    Join Date
    Apr 2001
    Location
    Asheville, NC
    Posts
    5,087
    Quote Originally Posted by aznfro
    Can anyone explain to me a 6 stroke?
    Bruce Crower's six-stroke engine. Good luck finding one anywhere else.
    Six in a row makes it go.

  31. #31
    skube1
    Guest

    rotarys

    every thing you should know!!!!


    http://www.turborx7.com/ttupgrades.htm Production Information
    http://www.turborx7.com/brochures.htm
    Understand your VIN
    Car Specifications
    Original Brochures
    Vacuum Diagrams
    Turbo Specifications
    Efini RX-7 (96-now)
    Stock Fuel System
    Catalytic Converter
    Concept Art and Design
    Technical Documents


    Products/Reviews
    Recommended Upgrades
    Fuel System Upgrades
    Power FC Instructions
    Single Turbo Upgrades
    Twin Turbo Upgrades
    Porting Info and links

    Nitrous usage

    Blitz FMIC Installation
    20B Rotary Engine Info
    Warnings
    Apexi RX-6 vs. Stock
    Greddy Pulley Kit


    Basics
    Apex Seals
    Turbocharger Basics
    Basics of Rotary Engines
    Rotary Engine History
    Gasoline/Ignition Info

    Detonation

    Wideband O2/Datalogit
    ECU Pictures/Info
    Rotary Engine Vehicles
    FAQs


    Media
    Home Page
    RX-7 Lingo
    Rotary Engine Pics
    Blow Off Valve Media
    Rotary History Pics
    Rotor and Housing Pics
    Polishing Links
    Mechanic Locations
    My RX-7 Mods
    My RX-7 Photo Gallery
    Links


    2nd Gen RX-7 FC
    1986 RX-7 Brochure


    Rotary Engine PickUp
    My '74 REPU project
    Mazda's REPU Page
    Pictures and Diagrams


    Other RX Models
    RX-3 Brochure
    RX-2 Brochure
    RX-8 Renesis Info/Specs






    1975 Rx2 13b ttbp microtech KILS8'S hotbodies12x brushless -lrp Nitro- Rx3 brushless dragster
    Last edited by skube1; 01-26-2013 at 08:33 AM.

  32. #32
    RC Racer
    Join Date
    Nov 2012
    Location
    San Jose
    Posts
    171
    Mercedes had a nice looking car for 69'-70-' they put a rotary engine in.
    I did however really like the 93-97 RX turbo, (Too pricey for my dealership to sell any at the time they came out, that area of Maine just wasn't a higher dollar fun market area.) you can keep the RX-8, that has got to be one of the ugliest cars Mazda has ever made.
    DJ

    Rustler,Slash 4X4, 1/10 Rally

  33. #33
    RC Turnbuckle Jr. humayrayakongkinaon's Avatar
    Join Date
    May 2011
    Location
    Long Beach, California
    Posts
    6,073
    Quote Originally Posted by djbrun View Post
    you can keep the RX-8, that has got to be one of the ugliest cars Mazda has ever made.
    hahahaha i agree, i'd pick the s2000 over rx-8 anyday.
    | Rally GT8 Powered By CC |

  34. #34
    RC Champion
    Join Date
    Mar 2011
    Location
    Usquam sed hic
    Posts
    1,568
    Quote Originally Posted by chickenhawk View Post
    Rotary engines aren't bad, but there is a reason they don't use them very much. They just don't win that many races.
    I think the main reason rotary engine's are not used more is the life factor, they seem to wear faster on average.
    Matthew 7:7

  35. #35
    RC Turnbuckle Jr. CarGuy7a's Avatar
    Join Date
    Dec 2008
    Location
    Gettin' Lucky In KY
    Posts
    3,876
    Here's the OS rotary mentioned earlier in the thread.
    Unfortunately that RC is Non-Traxxas Had to remove it according to the rules.
    NN
    Last edited by Nitronaught; 01-30-2013 at 02:48 PM. Reason: Non-Traxxas RC

  36. #36
    RC Turnbuckle Jr. pavmentsurfer's Avatar
    Join Date
    Jul 2009
    Location
    Ontario, Canada
    Posts
    11,145
    What's up 2006. Nice to see you again.
    Pede, Summit,
    ERBE, Rally,
    Motley Crew, 1SQ

  37. #37
    RC Qualifier
    Join Date
    Dec 2012
    Location
    Newcastle, Australia
    Posts
    941
    This may sound stupid, but could you make a rotary nitro? I understand nitros have no ignition system and run purely off revs and heat but could it work?
    Slugs are just naturally aspirated snails

  38. #38
    RC Turnbuckle Jr. CarGuy7a's Avatar
    Join Date
    Dec 2008
    Location
    Gettin' Lucky In KY
    Posts
    3,876
    Quote Originally Posted by JoelRobbo View Post
    This may sound stupid, but could you make a rotary nitro? I understand nitros have no ignition system and run purely off revs and heat but could it work?
    Yes. That's how the OS rotary I posted the link to that got deleted works I think it's classified as a 4 cycle nitro engine.

  39. #39
    RC Qualifier
    Join Date
    Dec 2012
    Location
    Newcastle, Australia
    Posts
    941
    Quote Originally Posted by CarGuy7a View Post
    Yes. That's how the OS rotary I posted the link to that got deleted works I think it's classified as a 4 cycle nitro engine.
    Can you buy them?
    Slugs are just naturally aspirated snails

  40. #40
    RC Turnbuckle Jr. CarGuy7a's Avatar
    Join Date
    Dec 2008
    Location
    Gettin' Lucky In KY
    Posts
    3,876
    Quote Originally Posted by JoelRobbo View Post
    Can you buy them?
    Yeah it's an RC airplane motor. They are pricey though in the $450 to 500 range.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •