Captain Amazing

Oh the things I would do to have an RX-7 next to my RX-8 in my garage.

KYLiquid

are you talking about the white scoot 4 rotor??? that car is simply amazing, i have quite a few videos of it, not only is the engine amazing, but the body kit on the FD makes it look like nothing else ive ever seen. it revs up so fast and sounds like and F1 car. I couldnt imagine how it must feel on the open road!!!

I heard that scoot was planing on making a 6 rotor FD

Captain Amazing

Link?

kenotic

My major reason for rotor over piston? Technology over brute force.

khtm

What other 1.3 Litre engine puts out 238 horses?

gh0st

its actually more like 215-220 hp.

race bike motors are capable of putting out MORE then 200hp to the wheels without forced induction and easily rev past 14,000rpm. and they are only .6L-1.0L. hell.. my street bike (2004 r1) has a redline of 14,000 rpm and with just a custom race exhausts, graves v stack and pc3, im putting 162 hp to the wheels.

dont get me wrong.. i LOVE the rotary, but you guys asked... :D

denward

rx8wannahave

Why a piston engine over a rotary?

Hmmm...the piston engine is:

More complex (a billion things can go wrong while the rotary either works or blows up, lol, j/k)
Bulky size
Slow growth (about 100 years worth of work yet they are still only about 20-35% efficient)


lol, but I'm just messing...you should just ask Mazda since they are the only ones who stuck it out with the little rotary.

Also, check out the ran-cam rotary engine...if that dream comes true it will be the death of the piston engine.

It's a "round-rotary" and so far (according to the company) an engine the size of a lawn mower engine (actually a little smaller) is making 40+ HP...it's the WAVE of the FUTURE...I tellz ya, lol.

MassiveAttack

Yeah, but imagine the HP this thing would be putting out if it were allowed to rev to 15k instead of a measly 9.5k!!!

RX8_Buckeye

Could someone provide a source for this statement? I see a lot of people making this claim, but it's a very vague statement. "Twice as hot"? How do you define "hot"? Anyone who has taken basic thermodynamics knows that 90 degrees F is not twice as "hot" as 45 degrees F. Is it the heat production that's being referenced?

Also, regarding the original topic, I wouldn't be surprised if the Renesis is actually CHEAPER to manufacture than a comparable piston engine. There are far fewer parts that are required, that's for sure. However, I'm unsure whether the machining costs for the rotor and rotor chamber offset these savings. Can anyone offer any insight?

PaulieWalnuts

It's usually defined as exhaust gas. On a rotary it's around 1800 degress where on a typcial piston engine it's 1000-1200 degrees.

RX8_Buckeye

Okay, thanks for the clarification. Still, 2000 deg F is NOT twice as hot as 1000 deg F. Fahrenheit/Celcius are not absolute scales.

PaulieWalnuts

Yes that's nice and everything but I'd like to see you try to drive a 3,000lb car with a 200 hp/14,000 rpm bike motor. Oh and good luck getting 200-300K miles out of it.

DreRX8

Funny thing is--I don't quite remember my FD being this thirsty for oil and gas--not to say it was a Prius but I get worse gas mileage in this than the FD--whenever I stayed off of the boost that is.

PaulieWalnuts

So in other words you got horrible gas mileage

DreRX8

BWHAHAHAHHAHAH---I drove it like I stole it. But it got decent gas mileage--when it was raining

KYLiquid

the 4 rotor FD i was talking about (videos on my home PC, ill have to look into posting some later when Im home from work) has an NA 4 rotor, with individual throtle bodies (ITB) and other work done.

here is some info on one of their turbo 13b cars, with some of the 'scoot secrets'

http://www.geocities.com/fdkai2000/scoot.htm 700hp

ok here are 2 video links :

3L 4 Rotor FD3S 500hp NA

http://members.dslextreme.com/users/erika/scoot.wmv
http://www.epoch-net.ne.jp/yasu/777/4re_001_b.wmv

they are clips from the Option 2 video I have that features this car.....

video one is the car, reving the motor, driving

video 2 is of the motor out of the car, being turned. no combustions, just listen to that sound....sooo sexy...even without air/fuel lol

looks SOOOO exotic for a FD.

i was thinking that a 4 rotor would be the limit to the engine size in a FD, after seeing some of the V8 and 3 rotor FDs around town (orlando) but they (Scoot) are saying that they are working on a 6 rotor version......wow.

KYLiquid

didnt suzuki make a car called the capachino in other markets...? if I remember it was powered by the 1.3L 4 cyl engine out of the hayabusa motorcycle and had a 12k redline, it was a small car, hatchback, like a metro....im sure it was detuned a little to give it more tq. but it might be a fun driver.

i have driven a lotus super seven replica (kit car) that was powered by a 1.3L 4cyl hayabusa motor....off the line it was a dog, but with its agresive 6speed trany and the small weight of the car ~1100 lbs, once you were moving on a road course it was a blast, and shots from about 50ish - 120ish went by pretty fast, and it had a redline of somehwere around 12K-ish

the other thing to keep in mind, while there are bike motors that make near the same HP as the rx8 with the same or less displacement....most of the time their TQ number is half of ours (80-90's)

gh0st

hey.. you guys asked what other 1.8 liter engine makes 238 hp.. i answered. and thats 200 hp to the wheels. tahts more like 250 hp at the crank. hell, moto gp bikes like the rc211v have to be DOWN TUNED to around 220-230 hp to be ridable.

besides.. id like to see a rx-8 do 200-300k miles without new seals.

but all in all, i just like the feeling of having both the highest reving mass produced car and bike in my garage.

denward

BTW.. there are LOTS of cars out there with bike engines.

missinmahseven

You may see 200-300 out of a renesis. Time will tell, but if it goes like the 12A and na 13B, yeah, you should see that much.

The big caveat is, whoever wants their rotary to last that long will have to make absolutely sure the cooling system is well-kept. Hoses, in particular, are killers. They degrade, then break, and one overheat is all a rotary needs to go meet its maker.

On the bright side, we don't have to worry about silly things as lash adjustment and timing belts

gh0st

i do have to agree.. our version of the 13b sure do seem a lot stronger then the 3rd gens.

oh well... im turboing anyways.

denward

Mugatu

iTrader: (1)

HAHAHAHAHA :D

Section 8

don't forget bad tuning. 1 Detonation will kill compression rather quickly.

snizzle

Well, not when you factor in volume. It can't be cheaper for them to produce given engine sales volumes such as the Nissan line. Mazda will never sell enough Rotary engines to compare unless they start using them in everything they make. Not to mention they have to eat the R&D that goes into these engines because they can't use the results for anything non-rotary. You must pay a cost to be unique.

RX8_Buckeye

Very true. You're probably right that the low volume application of the Renesis kills any potential cost-savings compared to a piston engine. Generally speaking though, comparing a rotary engine to a piston engine with similar volumes and R&D costs, I would think it would be cheaper.

NomisR

Yeah, and people are complaining about the low torque for our cars, imagine what they would do with a motorcycle engine? Comparatively, we make pretty good hp/tq for our engine size.