Mazda RX8

[LS20]

Originally posted by: Bignate603
They need something to overcome the lack of low end torque. That's the most fun part of a fast car. You hit the gas and it GOES.

thats what a transmission is there for

even tho the redline is at 9000, i heard it can safely rev to wayyyyy higher speeds--as most rotaries can (atleast over its piston-engine counterparts)

whoever says that that engine speed is "ridiculously" high must be too accustomed to pushrods... i take my car to 7500 daily and it feels and sounds great :-D

 

[ElFenix]

Originally posted by: Roger

they're essentially two-cycle motors which helps the power a bit but hurts emissions, which is why they've been very limited in application

Far from it, two cylces implies that there are reciprocating parts which the Rotary engine does not contain.
Yes they do not contain valves as in in a conventional four stroke engine, but they do not contain pistons either.

Here is a simplified flash animation

Rotary engines tend to have large horsepower/displacement ratios and low torque/displacement ratios because of the reduced leverage of the main offset output shaft.
Earlier Rotary's had a problem with increased exhaust emissions and slow catalyst lightoff, the newer designs (RX8) have drastically redesigned intake and exhaust ports which allow higher power outputs while emitting lower emissions and having higher exhaust temperatures which warm up the catalyst much quicker.

yeah thanks i know what a rotary engine is

 

[Amused]

Originally posted by: LS20

Originally posted by: Bignate603
They need something to overcome the lack of low end torque. That's the most fun part of a fast car. You hit the gas and it GOES.

thats what a transmission is there for

even tho the redline is at 9000, i heard it can safely rev to wayyyyy higher speeds--as most rotaries can (atleast over its piston-engine counterparts)

whoever says that that engine speed is "ridiculously" high must be too accustomed to pushrods... i take my car to 7500 daily and it feels and sounds great :-D

I have no problem with a 9000RPM readline. I just don;t like it that you have to rev it up past 5-6000 for it to have any balls.

 

[LS20]

whats wrong with revving the engine at that speed? since obviously its designed to be run at high RPMS, theengine wont feel like its being "strained" operating like that ?

 

[CraigRT]

Mint car. that's a way cool chariot!

 

[JYDog]

Put a battery in it(Hybrid) and that should fix the low-end torque problem around town.

 

[Eli]

Originally posted by: JYDog
Put a battery in it(Hybrid) and that should fix the low-end torque problem around town.

That's actually a really good idea. Batteries suck, though. I'm waiting for fuel cells to become a viable alternative to batteries.

 

[Howard]

Originally posted by: ElFenix

Originally posted by: Roger

they're essentially two-cycle motors which helps the power a bit but hurts emissions, which is why they've been very limited in application

Far from it, two cylces implies that there are reciprocating parts which the Rotary engine does not contain.
Yes they do not contain valves as in in a conventional four stroke engine, but they do not contain pistons either.

Here is a simplified flash animation

Rotary engines tend to have large horsepower/displacement ratios and low torque/displacement ratios because of the reduced leverage of the main offset output shaft.
Earlier Rotary's had a problem with increased exhaust emissions and slow catalyst lightoff, the newer designs (RX8) have drastically redesigned intake and exhaust ports which allow higher power outputs while emitting lower emissions and having higher exhaust temperatures which warm up the catalyst much quicker.

yeah thanks i know what a rotary engine is

So why did you say rotaries were essentially two-strokes? Wankel-cycle engines can't be compared with Otto-cycle engines because , for one, the stages of combustion don't even take place in the same chamber, and two, they don't have valves.

 

[Eli]

Originally posted by: Howard

Originally posted by: ElFenix

Originally posted by: Roger

they're essentially two-cycle motors which helps the power a bit but hurts emissions, which is why they've been very limited in application

Far from it, two cylces implies that there are reciprocating parts which the Rotary engine does not contain.
Yes they do not contain valves as in in a conventional four stroke engine, but they do not contain pistons either.

Here is a simplified flash animation

Rotary engines tend to have large horsepower/displacement ratios and low torque/displacement ratios because of the reduced leverage of the main offset output shaft.
Earlier Rotary's had a problem with increased exhaust emissions and slow catalyst lightoff, the newer designs (RX8) have drastically redesigned intake and exhaust ports which allow higher power outputs while emitting lower emissions and having higher exhaust temperatures which warm up the catalyst much quicker.

yeah thanks i know what a rotary engine is

So why did you say rotaries were essentially two-strokes? Wankel-cycle engines can't be compared with Otto-cycle engines because , for one, the stages of combustion don't even take place in the same chamber, and two, they don't have valves.

Neither do 2-cycle engines, though.. Have valves, that is.

I think he just meant that they're like a 2-cycle engine in that they don't have valves, but I agree with you.. they can't be compared...

 

[boyRacer]

<--- still prefers the fickle RX-7 over RX-8...

 

[phaserx]

i think the rx8 is the sharpest looking car since the infiniti g35 coupe .. well, sharpest looking for what the average joe can afford anyways..

 

[Amused]

Originally posted by: LS20
whats wrong with revving the engine at that speed? since obviously its designed to be run at high RPMS, theengine wont feel like its being "strained" operating like that ?

It takes time to get your revs up that high. Therefore you don't have that power right from the start.

 

[puffpio]

Originally posted by: Eli

Originally posted by: specktre everyone I talk to that claims to be into japanese sports cars don't like the 1.3L rotarty engine. they say that those motors aren't built for over 30,000 miles, they aren't durable. I say they are morons. The rotary engine has less moving mass and less moving parts than a "normal" "rice rocket" motor. I like rx-7's and I think the rx-8 is gonna be sweet. my dream car (vin deasel's rx-7 in the fast and the furious)

well..... that's another area of concern. I have never heard of a rotary with 250,000 miles on it. The apex seals tend to wear out... That said, it should last considerably longer than 30,000.

well i've heard of many NA rotaries going over 100000..but no turbo rotaries

 

[Byte]

you want to wait for the mazdaspeed incarnation of the RX8

link

 

[slikmunks]

Originally posted by: Byte
you want to wait for the mazdaspeed incarnation of the RX8

link

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that's the photochopped version... the mazdaspeed rx8 is 4 door, like the rx8
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Originally posted by: Amused

Originally posted by: LS20
whats wrong with revving the engine at that speed? since obviously its designed to be run at high RPMS, theengine wont feel like its being "strained" operating like that ?

It takes time to get your revs up that high. Therefore you don't have that power right from the start.

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it does take time, but if you get a lightweight flywheel.. wheeeeeEEEEeeee
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Originally posted by: boyRacer
<--- still prefers the fickle RX-7 over RX-8...

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me too, but i wouldn't mind having a ported renesis in my rx
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Originally posted by: specktre
everyone I talk to that claims to be into japanese sports cars don't like the 1.3L rotarty engine. they say that those motors aren't built for over 30,000 miles, they aren't durable.

I say they are morons. The rotary engine has less moving mass and less moving parts than a "normal" "rice rocket" motor.

I like rx-7's and I think the rx-8 is gonna be sweet.

my dream car (vin deasel's rx-7 in the fast and the furious)

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problem with rotaries (i've said this many times, and have seen 1st gen rx7's running on the original motor at 200k mi) is that they respond really well to mods and people like to tend to mod more... getting into large turbos, large porting and all that stuff... the problem is that people like to mod, but a lot don't think upgrade fuel injectors, pump, and rails with the turbo. The reason rotaries have a rep for going early is that yes, they are kind of fragile, they're really succeptible to detonation... that's a rotary killer... so tune ur rotary right, and barring extreme cases, you'll get lots of miles on ur engine...

rx8 will be sweet... i'm trying to talk my dad into getting one...

as for your dream car, you don't want his car... his car is a total poser car, it's auto, NOT a 3 rotor, as depicted in the movie, basically stock with a bunch of gauges, and basically, it's a riced out rx7 sad to see, but that's what it is...
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Originally posted by: Eli

Originally posted by: Amused

Originally posted by: Bignate603
They need something to overcome the lack of low end torque. That's the most fun part of a fast car. You hit the gas and it GOES.

I agree. Like Honda's HP engines, rotary engines lack torque, which means to get good performance you have to wind these things up like humming birds and stay in that ridiculously high RPM zone, or it bogs like tiny 4 banger.

You do realize that they're getting 250HP and 152.7ftlbs of torque from a 1.3L engine?

Anyway, it's all in the design. As with everything, its a trade off. They could design it to give more torque, but it would sacrifice RPMs.

I don't mind high-revving engines one bit. IMO, they're more fun.. especially coupled with a 6 speed.

What isn't to like about a 8500RPM redline?

----------------
yeah, that's the downside, it's not too much torque... but yeah, i love my 8500-9000 redline...
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Originally posted by: Eli

Originally posted by: Roger

they're essentially two-cycle motors which helps the power a bit but hurts emissions, which is why they've been very limited in application

Far from it, two cylces implies that there are reciprocating parts which the Rotary engine does not contain.
Yes they do not contain valves as in in a conventional four stroke engine, but they do not contain pistons either.

Here is a simplified flash animation

Rotary engines tend to have large horsepower/displacement ratios and low torque/displacement ratios because of the reduced leverage of the main offset output shaft.
Earlier Rotary's had a problem with increased exhaust emissions and slow catalyst lightoff, the newer designs (RX8) have drastically redesigned intake and exhaust ports which allow higher power outputs while emitting lower emissions and having higher exhaust temperatures which warm up the catalyst much quicker.

Once Again, Roger cleans up a thread.

Damn, beat me to it though. But yeah, they drastically redesigned the intake and exhaust ports.. which ended up cleaning them up a lot, as far as emissions go.


Rotary engines are very cool. I wouldn't mind one bit if they became a little more "mainstream".

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the side ports were a great idea (that was the change in the intake and exhaust ports), it allows unburned fuel to be "recycled" into the chamber... but then, us rotary guys lose that nice little POP backfire/afterburn when we change gears at high gear The side ports also begs the question, how are they (if they are) going to make a 3 rotor renesis? you can't put 3 rotors side to side to side all with exhaust & intake ports on the side... one's gotta be in the middle...
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Originally posted by: Bignate603
They need something to overcome the lack of low end torque. That's the most fun part of a fast car. You hit the gas and it GOES.

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that's what the 9k rpm redline is for
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Originally posted by: Amused

Originally posted by: Eli

Originally posted by: Amused

Originally posted by: Bignate603
They need something to overcome the lack of low end torque. That's the most fun part of a fast car. You hit the gas and it GOES.

I agree. Like Honda's HP engines, rotary engines lack torque, which means to get good performance you have to wind these things up like humming birds and stay in that ridiculously high RPM zone, or it bogs like tiny 4 banger.

You do realize that they're getting 250HP and 152.7ftlbs of torque from a 1.3L engine?

Anyway, it's all in the design. As with everything, its a trade off. They could give it more torque, but it would sacrifice RPMs.

I don't mind high-revving engines one bit. IMO, they're more fun.. especially coupled with a 6 speed.

What isn't to like about a 8500RPM redline?

9000.

Hey, engines with high revving powerbands are nice on the track where you have the ability to keep the revs up. But in city driving? Come on.

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my 8500rpm redline is fine for city driving... hell, when are you going to be driving in the city to need all the power? when you need to, it's there, so it's all good
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whew, that was a long post!!!

 

[slikmunks]

i wonder how many people are actually gonna read my post...

 

[Howard]

Originally posted by: Eli

Originally posted by: Howard

Originally posted by: ElFenix

Originally posted by: Roger

they're essentially two-cycle motors which helps the power a bit but hurts emissions, which is why they've been very limited in application

Far from it, two cylces implies that there are reciprocating parts which the Rotary engine does not contain.
Yes they do not contain valves as in in a conventional four stroke engine, but they do not contain pistons either.

Here is a simplified flash animation

Rotary engines tend to have large horsepower/displacement ratios and low torque/displacement ratios because of the reduced leverage of the main offset output shaft.
Earlier Rotary's had a problem with increased exhaust emissions and slow catalyst lightoff, the newer designs (RX8) have drastically redesigned intake and exhaust ports which allow higher power outputs while emitting lower emissions and having higher exhaust temperatures which warm up the catalyst much quicker.

yeah thanks i know what a rotary engine is

So why did you say rotaries were essentially two-strokes? Wankel-cycle engines can't be compared with Otto-cycle engines because , for one, the stages of combustion don't even take place in the same chamber, and two, they don't have valves.

Neither do 2-cycle engines, though.. Have valves, that is.

I think he just meant that they're like a 2-cycle engine in that they don't have valves, but I agree with you.. they can't be compared...

Two-strokes still have exhaust valves.

 

[Howard]

slikmunks, I read it, no fear.

You know, I hope Mazda comes out with a 2.0L or greater displacement RENESIS rotary (possibly a 3-rotor version?). Everything else being the same, it should make almost 400HP and 350lb-ft of torque. What a blessing it would be to have a turboed version.

 

[Chadder007]

Originally posted by: Eli

Originally posted by: specktre
everyone I talk to that claims to be into japanese sports cars don't like the 1.3L rotarty engine. they say that those motors aren't built for over 30,000 miles, they aren't durable.

I say they are morons. The rotary engine has less moving mass and less moving parts than a "normal" "rice rocket" motor.

I like rx-7's and I think the rx-8 is gonna be sweet.

my dream car (vin deasel's rx-7 in the fast and the furious)

well..... that's another area of concern. I have never heard of a rotary with 250,000 miles on it. The apex seals tend to wear out...

That said, it should last considerably longer than 30,000.

Ive seen one with 185,000 miles on it....BUT that is with the SECOND Engine, about to be third!

 

[apoppin]

Originally posted by: Bignate603
They need something to overcome the lack of low end torque. That's the most fun part of a fast car. You hit the gas and it GOES.

I have two 1976 Mazda Cosmos ("rare" RX-5s) . . . if you want "torque" you change to a heavier flywheel. My stock 13B (1.3 L) engine put out well over 250HP with "normal" carburation. And can totally "burn" rubber first through third - I have "surprised" many a Porsche, etc (until about 120MPH when the Porsche catchs up and starts to pull away).

And emissions controls are more difficult to implement on a rotary engine without crippling it.

EDIT: Apex seals are no longer a problem. Even though the rotarys need to be rebuilt more often than a conventional engine (they now routinely get over 150K miles between rebuilds) they are MUCH easier to rebuild (two guys can lift the engine out of the compartment).

A "problem" with Rotarys is that they USE oil - the oil is metered (drop by drop) into the gasoline so you NEED to add a quart occasionally (even in a "new" engine) - the newer RX7s won't start if the oil is "low".

 

[JYDog]

I think Rx8 is a sweet car but I myself would wait for a harder version, with more power, 247hp isn't much when the next honda Accord packs 240hp. :Q
Granted, the Rx8 comes into its own on the handling side, still I would want alittle more straight line punch.

 

[apoppin]

Originally posted by: JYDog
I think Rx8 is a sweet car but I myself would wait for a harder version, with more power, 247hp isn't much when the next honda Accord packs 240hp. :Q
Granted, the Rx8 comes into its own on the handling side, still I would want alittle more straight line punch.

Isn't the RX-7 going to be REintroduced as the "performance/muscle" car? To sell alongside the RX8?

If you want more power - remember the RX-7 is a light car - get the turbo . . . it'll give you everything you want and more (engine rebuilds will be a bit more often than the non-turbo version).

EDIT: My Cosmos gave me MORE power than I ever needed (I never quite hit the Ultimate Redline of 11,000 RPM. . . ) AND I have the speeding tickets to prove it.

 

[JYDog]

Originally posted by: apoppin

Originally posted by: JYDog
I think Rx8 is a sweet car but I myself would wait for a harder version, with more power, 247hp isn't much when the next honda Accord packs 240hp. :Q
Granted, the Rx8 comes into its own on the handling side, still I would want alittle more straight line punch.

Isn't the RX-7 going to be REintroduced as the "performance/muscle" car? To sell alongside the RX8?

If you want more power - remember the RX-7 is a light car - get the turbo . . . it'll give you everything you want and more (engine rebuilds will be a bit more often than the non-turbo version).

The next Rx7(if it is) would be my choice among just about any car its put against.

 

[apoppin]

After all these years, I am finally going to sell my RX-5s . . . my 'racing' days are over . . .

 

[dawheat]

If the RX-8 does well, then the next RX-7 is rumored to be a 300hp, 2600lb, 2 seater rocket with possibly 3 rotaries vs the 2 in the RX-8. I still remember watching the last gen RX-7 dust the 911 Turbo of that year around the Nurbugring.

In any case, early review of the RX-8 have reviewers giving it high marks for a great chasis and balance. Yes you need to row the gearbox for max power, but the engine is plenty tractable down low. No you won't get a big rush under 5000rpm, but its plenty for city driving. And when you do get some open road...