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Just a few questions for all you car nuts out there. i

'm a fan of american muscle and naturally i love the hemi engines. but lately ive been hearing about rotary engines being very powerful but i doubt they can produce as much power as a normal piston engine mainly because they only have 2 rotors and their for couldnt be as efficent as piston engines in producing power. are they more powerful?

which do you think is better and why?
 

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

Which is more powerful? Are you serious?

In stock form, a V8 has more hp/tq. Rotary engines are low on the torque. Rotaries rev much higher than a v8 though, and with something like 80% less moving parts. Rotaries are lighter, and more reliable *with proper maintenance*. The thing that goes on them is apex seals, so you need to be careful about that. They also dont like overheating. If you overheat one, you minus well relplace it. They are great motors and a lot of fun. Super quiet, even with a straight exhaust.

If you are going to modify it, well, the only limit on power is your wallet.
 

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King of Oilernation
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In terms of efficiency, a rotary kills a reciprocating engine. And the don't necessarily have to have only two rotors. But pound for pound they are nearly as powerful as a V8. They are definitely torque shy and love to revved- but even that is slowly being improved.
 

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ever know anyone with a rotery when it is very cold? those i've known usually need a ride. injector in the top spark plug at the bottom = fuel fouled plug
 

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spacemonkey said:
ever know anyone with a rotery when it is very cold? those i've known usually need a ride. injector in the top spark plug at the bottom = fuel fouled plug
I've been a passenger in my brother's RX-7s in the middle of January in New England. Never a problem with the engine. The rest of the cars however...
 

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hahah my first post on a sportbike forum is about rotarys.

The RX-7 can produce huge amounts of power out of a small 1.3L engine. I make 400hp with an aftermarket single turbo. I love the rotary.
 

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My brother is a tech a mazda dealership and has been for the last 15 yrs he said when winter came the mazda techs never had a slow day when the rx7's were big
 

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The turbo charged rotarys can be made reliable with the proper cooling system upgrades and a good conservative tune. And they can still make big numbers.
 

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I would personally wait and see if Mazda has fixed their rotary engines on their new cars. The old ones in the RX-7's are less than reliable IMO. Those motors need rebuilt at a fairly low milage.

If I had to chose I would take the V's not the rotaries.

Rotaries will never be big, by then we will be using hydrogen or something else for fuel and have a totally new set-up.

Rotaries do rev quicker though correct??
 

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It depend on what you want out of the motor. If you want to pull trees or do a 12 o'clocks with your cage, you want a big block zz502 blown, NOS, bored & stroke.

If you want to have lots of power and a neutral weight bios, then your gonna want a good old wankel :)
 

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Rule #1.

There is no replacement for displacement


also the cost of fixing rotary engines VS Piston engines is huge.
 

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If rotarys were where its at... :bitchslap thats where everybody would be at.
Not saying they don't have potential, thats obvious, but if ya get one, just make sure you got a Mazda dealer close cause them things ain't easy to work on.
 

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rotarys are nice if you keep them maintained, I know of people blowing apex seals at 70k. Yes the low end tourque is... not there but if you keep them in the upper rpm range you shouldn't have a problem.
 

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Warp_Speed said:
Rule #1.

There is no replacement for displacement


also the cost of fixing rotary engines VS Piston engines is huge.
Oh my god, do you big displacement guys honestly think that your 7.2 litre+ engines producing 500 horsepower is impressive? :bitchslap I hardly think that the horsepower/size ratio is that cool... maybe if the engine was about half that size it would be decent...You can get just as much power from a smaller engine and have it be more reliable/have better gas mileage (though definately not the gas mileage with a rotary, if youre looking for a practical car go somewhere else. My friend has a bridge-ported rx-7 that gets about 8mpg which is the thing that stops me from getting one). In terms of efficiency the rotary is way petter than a standard engine as it has the seperate chambers as it were (cant think of another word for em) for injection,combustion, and exhaust in one roatary housing instead of having pistons moving up then injection, then moving down for compression and combustion, then moving back up again for exhaust...etc.
 

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Rotary engines are much more effecient. They are easy to work on once you grasp the concept of them as well. The motor actually comes apart in slices. It's great. They say one rotor is equal to about 2 cylinders. They do make three rotor motors as well. They do need a proactive maintenance owner though. What most people don't realize is that they actually inject oil to lubricate the apex seals. If oil level gets too low it does not lubricate the seals as well anymore. I do work for mazda. I am not a big fan of the RX-8's because the rest of the car is over engineered. However the ingenuity of the rotary motor is unmatched.
 

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NinjaBum said:
Oh my god, do you big displacement guys honestly think that your 7.2 litre+ engines producing 500 horsepower is impressive? :bitchslap I hardly think that the horsepower/size ratio is that cool... maybe if the engine was about half that size it would be decent...You can get just as much power from a smaller engine and have it be more reliable/have better gas mileage

when you know what your talking about let me know.

Very simple fact that a b***** displacement engine makes more power. You can make just as much w/ a smaller motor but it takes more work/money/boost. You can see 4 cly motors pushing 500 HP but look at what level of boost they need to run to accomplish that where as in a V8 motor you can do it w/ 10 PSI

Before you start banging to hard on big displacment motors IE.. V8's... IE, Fords just take a look at who makes Mazda and the RX-7, RX-8... yeah thats right Ford :neener
 
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