1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

how do you get a rotory do 14000rpm

Thread Tools
 
Search this Thread
 
Old 06-24-04 | 11:22 PM
  #1  
capri93's Avatar
Thread Starter
The thing
 
Joined: Mar 2004
Posts: 388
Likes: 1
From: palmerton pa
how do you get a rotory do 14000rpm

as the title says what does it take to do this? lighter race rotors among other things I have no real plans to of taking it to this extreme but 9-10k would be cool.
Old 06-24-04 | 11:22 PM
  #2  
lovintha7's Avatar
Suicidal Death Missile

 
Joined: Mar 2004
Posts: 1,782
Likes: 0
From: Newport News, Virginia
A ballistic shield for starters.
Old 06-24-04 | 11:27 PM
  #3  
YapaKanichi's Avatar
Smile Like a Donut
 
Joined: Feb 2004
Posts: 1,236
Likes: 0
From: Don't you wish you knew....
hey to talkabout ballastic shields where are they and how much
Old 06-24-04 | 11:31 PM
  #4  
lovintha7's Avatar
Suicidal Death Missile

 
Joined: Mar 2004
Posts: 1,782
Likes: 0
From: Newport News, Virginia
Maybe Jeg's or Summit?
Old 06-24-04 | 11:31 PM
  #5  
capri93's Avatar
Thread Starter
The thing
 
Joined: Mar 2004
Posts: 388
Likes: 1
From: palmerton pa
yeah i know about that stuff like tranni blankets and and drive shaft cradle the safty eq
Old 06-24-04 | 11:33 PM
  #6  
lovintha7's Avatar
Suicidal Death Missile

 
Joined: Mar 2004
Posts: 1,782
Likes: 0
From: Newport News, Virginia
Tranny blanket = ballistic shield
Old 06-24-04 | 11:35 PM
  #7  
Xavier8's Avatar
Never satisfied

 
Joined: Aug 2003
Posts: 305
Likes: 0
From: San diego, CA
get a renesis-9500 rpm fuel cutoff-just playing
Old 06-24-04 | 11:36 PM
  #8  
lovintha7's Avatar
Suicidal Death Missile

 
Joined: Mar 2004
Posts: 1,782
Likes: 0
From: Newport News, Virginia
Oh, btw there are 2 Renesis engines with computers on ebay, starting at $3k
Old 06-24-04 | 11:44 PM
  #9  
capri93's Avatar
Thread Starter
The thing
 
Joined: Mar 2004
Posts: 388
Likes: 1
From: palmerton pa
boy are we off the topic here
Old 06-24-04 | 11:56 PM
  #10  
85rotarypower's Avatar
love the braaaap
 
Joined: Jul 2003
Posts: 3,771
Likes: 5
From: Bognor, Ontario
Lets see, to start off you would need:

-Carbon apex seals
-3rd gen seal springs
-hardened stationary gears
-race clearenced and lightened rotors
-lightweight flywheel
-LARGE carb
-upgraded oiling system
-underdrive pullies so you don't fry your water pump and alternator.

I'm sure thats not all. I am by far not an expert on this subject. I don't even know if its possible to make a rotary turn that fast. But thats probably a good starting point.
Old 06-25-04 | 12:00 AM
  #11  
ScrapFC's Avatar
Emerald Triangle for life
iTrader: (5)
 
Joined: Jan 2002
Posts: 552
Likes: 0
From: Fort Collins, CO
I've been thinking about this and I have a few suggestions:
First, you really really need a center support bearing! Eshaft deflection is going to be brutal at those RPMs if the eshaft is only being supported from the ends.
Second, you need the lightest possible rotors. Maybe start with Renesis rotors and shave them down like Racing Beat does with the earlier rotors?
Third, you need really strong side gears. Maybe dual side gears per rotor?
Fourth, you need a LOT of port area/timing. A large PPort should do it. Maybe a combi-port? (Side ports with a PPort that opens at high RPM)
Of course, you'll also need a flywheel/clutch/trans combo that can stand up to that sort of RPM.
Don't forget some SERIOUS scatter protection! When that mother grenades at 14K+ (think missed shift) it's going to have some INCREDIBLE KE behind it!

BTW, if anyone manages to build such a beast I WANT VIDEO!!
Old 06-25-04 | 12:06 AM
  #12  
Junia's Avatar
Uchinanchu
 
Joined: Sep 2002
Posts: 937
Likes: 0
From: Orlando, FL
I think it simply just takes air and fuel. As long as you keep feeding the engine the air and fuel that it needs it should keep going until it just pops or something else in the driveline pops.
Old 06-25-04 | 12:10 AM
  #13  
85rotarypower's Avatar
love the braaaap
 
Joined: Jul 2003
Posts: 3,771
Likes: 5
From: Bognor, Ontario
At that engine speed, a stock engine wouldn't last more than 3 seconds. Supposedly 8500 rpm is the max safe speed for a stock rotary. At 8400 rpm the apex seals start to "chatter". If you hold the engine at 10000 rpm your steel apex seals are going to eat your housings for lunch.
Old 06-25-04 | 12:11 AM
  #14  
REVHED's Avatar
Hunting Skylines
 
Joined: Apr 2001
Posts: 3,431
Likes: 4
From: Brisbane, Queensland, Australia.
First of all, 14000rpm is a bit unrealistic. You'll find even the most highly strung peripheral ports will have a useable power band up to around the 10-11000rpm mark at the most. The only time you'd hold it for longer is if you're coming up to a corner and it wouldn't make sense to change into the next gear.

To achieve these sort of numbers you obviously need to start with an engine capable of making power at such high revs. This means a peripheral or large bridge port. As far as the engine internals go you'd need carbon apex seals, lightened, circlipped and clearanced rotors, tougher stationary gears and the usual oil mods.

Circlipping involves machining the rotor to accept a circlip that holds the rotor gear in place and stops it from "walking" at high revs. Clearancing is when you machine the sides of the rotor to provide more clearance between the rotor and side housings to prevent contact caused be the eccentric shaft flexing. Some people also clearance between the rotor tips and rotor housing.

There are other things you can do as well. Guru here in Australia have a two-piece eccentric-shaft that incorporates an extra bearing in the centre housing to prevent the e-shaft from flexing. They've also developed their own rotor/stationary gear profile which is supposedly far stronger than the Mazda design which hasn't really changed since the early days.
Old 06-25-04 | 12:22 AM
  #15  
capri93's Avatar
Thread Starter
The thing
 
Joined: Mar 2004
Posts: 388
Likes: 1
From: palmerton pa
so this 14000 thing is a bit out there but you guys got the general point i was looking for and thanks i think for now im just gonna work with porting and turboing my 81 and 84 then maybe work up to the higher reving motor. What kinda rpms are people running with simpler upgrades like carbon seals, Br port, bigger carbs better exhaust the more common stuff
Old 06-25-04 | 12:26 AM
  #16  
peejay's Avatar
Old [Sch|F]ool
 
Joined: May 2001
Posts: 12,637
Likes: 466
From: Cleveland, Ohio, USA
Re: how do you get a rotory do 14000rpm

Originally posted by capri93
as the title says what does it take to do this? lighter race rotors among other things I have no real plans to of taking it to this extreme but 9-10k would be cool.
Four big bags of crack.
Old 06-25-04 | 12:31 AM
  #17  
peejay's Avatar
Old [Sch|F]ool
 
Joined: May 2001
Posts: 12,637
Likes: 466
From: Cleveland, Ohio, USA
Now that that is out of the way...

If you want a really high revving power plant, a peripheral port won't cut it. You'll need a monster bridge in order to get the port area and port timing to suit.

But why bother? Internal stresses go up by orders of magnitude after about 8k, and accelerative losses from rotational inertia dictate that the best engine is the one that makes its power at the lowest RPM possible to make that power. There is no real point to building an engine to rev higher than 10k.

Stock 3mm seals don't start to chatter at 8400. They start to chatter at *6200*. Chattering becomes fatal at about 8500.
Old 06-25-04 | 08:42 AM
  #18  
Junia's Avatar
Uchinanchu
 
Joined: Sep 2002
Posts: 937
Likes: 0
From: Orlando, FL
I've read in alot of places where people say don't rev the motor above 8500 on stock internals but I know plenty of people running stock internals running 10,000 on a regular basis without any problems.
Old 06-25-04 | 10:10 AM
  #19  
vipernicus42's Avatar
Rotoholic Moderookie
iTrader: (4)
 
Joined: May 2002
Posts: 5,962
Likes: 33
From: Ottawa, Soviet Canuckistan
There's no point to 14,000 RPM at all. As REVHED said, there isn't any usable power up there, and even JESUS PADILLA didn't go above 11,000.

It would take more money than it's worth, and there'd be no real benefit to it.

Jon
Old 06-25-04 | 12:35 PM
  #20  
Junia's Avatar
Uchinanchu
 
Joined: Sep 2002
Posts: 937
Likes: 0
From: Orlando, FL
I don't think that he's worried about whether theres usable power up there or not. I think he just wants to know if it will spin all the way up there or not and what it would take to get it up there.
Old 06-25-04 | 01:15 PM
  #21  
OtakuRX's Avatar
The Rotorheaded Geek
iTrader: (1)
 
Joined: Mar 2002
Posts: 920
Likes: 0
From: exit 8 in Manchester, NH
how do you get a rotory do 14000rpm

Very carefully
Old 06-25-04 | 01:48 PM
  #22  
hotty's Avatar
Rotary Enthusiast
 
Joined: Oct 2001
Posts: 898
Likes: 0
From: T.O
easily.. you rev it up to 18,000 rpm and smile like hell.
Of course i'm not talking a full size 12a or 13b, however, there are small RC engines like the Graupner/OS Model Engine 5 cc - 2500- 18,000 rpm 1.27 BHP

254HP PER LITER :O

I wouldnt waste my time revving a full size rotary about 10k EVER. even 9 is a LOT of rpm.
Daryl
Old 06-25-04 | 02:26 PM
  #23  
rototiller1's Avatar
Inspector, Falcon Jet

 
Joined: Mar 2003
Posts: 430
Likes: 0
From: Little Rock
25,000 Dollars
Old 06-25-04 | 03:37 PM
  #24  
LEZNAY's Avatar
Junior Member

 
Joined: Jun 2004
Posts: 6
Likes: 0
From: HARLOW ESSEX
i thnk the point is more if it can get to 14000 with out exploding it can do 9 with out exploding and you and force it better, meaning if you push it to do 14k 9k is walk in the park.
Old 06-25-04 | 04:39 PM
  #25  
capri93's Avatar
Thread Starter
The thing
 
Joined: Mar 2004
Posts: 388
Likes: 1
From: palmerton pa
thats more what i ment i want to have my engine still running should i miss a gear or **** up a clutch at 8 or 9k not run 14k constantly i dont plann on ever hiting that mark i just want a little leeway in case of a screw up on my part



All times are GMT -5. The time now is 11:19 AM.