How fast is a RX8?

[mqt55s]

that f1 technology comment was meant for a DC2R....... (read a few posts back and you will see)

indeed. people getting attacked left, right and centre on this forum lol. hot chicks thread ftw.

neways, back on topic, only downfall with the rx8 i'd have to say is the atrocious fuel consumption. although being a 1.3l, its categorized in the 2.6L class isnt it? well it still drinks way more petty than a 6 cylinder. closer to a v8. damn harsh on the bank account lol.

but i love how smooth they are. can barely tell its on when its idling. would probably be due to the rotors spinning in one direction vs pistons rapid change in direction.

i'd be interesting to hear from people who have actually driven an rx8 and a honda itr/s2k.

[tank]

that f1 technology comment was meant for a DC2R....... (read a few posts back and you will see)

Thanks for the clarification.

I got so confused when I read that sentence, because someone was saying that a RX8 can match the DC2r on the track.

Stock for stock, a well driven DC2r is very hard to beat on any race tracks in NSW.

[SeverAMV]

So, which part of the RX-8 has F1 technology??? The renesis rotary engine??? I hope not because all F1 engines are piston.

Mazda doesn't even have a F1 team.

Mazda used to be in the 24 hours Le Mans races, but their rotary engine was deemed to be waaaaaaaaaaaaaaaaaaaaaay too fast when their quad rotor won, so the europeans banned the rotary from the Le Mans races.
GTR was also deemed too fast for races in some countries and were also banned from certain races.
but you dont see vtec being banned...
not everyone needs a formula 1 team to be successful. subaru built their fame on rallying, and they net more sales than honda last time i checked. nissan dont do f1 and they aint doin half bad. mitsubishi too.

anyway, not dissing either. rotaries are good engines, and efficient power-wise, but they lack low down torque without a supercharger/turbocharger.

there were attempts to turbocharge the rx-8, i believe there was an RX-8 turbo model by mazdaspeed. was projected at 250kw.

reason why people wouldnt normally compare a honda with the rx-8 is because the rx-8 is a GT car, most honda's are not, with the s2000 and nsx being the only exceptions. anyone can argue with me as much as they want with this point, but a requirement of the GT car requires that the car be rear wheel drive.

rotaries dont really need vtec, because they aren't inefficient enough to need something as such to make it more efficient - power-wise that is. mazda stuck on extra exhaust ports and the power just went up to 177kw for the renesis, which isnt too bad. aside from that, mazda claimed that it was relatively unchanged from the old 13b non turbos. can anyone say that honda could do such a minimal change and gain a big boost? with just an exhaust system alone? because thats what mazda did.

as to the motor part. as the rx8 completes 3 cycles with one revolution, the motor rotates at a third of the rate claimed on your tacho. so when you hit 9000rpm, your rotors are spinning at 3000rpm.
whereas with a piston motor, 8000rpm is 8000rpm. theres a difference in efficiency right there. less moving parts in rotary = more efficient too.

anyway... *ducks out to avoid further flaming*

[aaronng]

but you dont see vtec being banned...
not everyone needs a formula 1 team to be successful. subaru built their fame on rallying, and they net more sales than honda last time i checked. nissan dont do f1 and they aint doin half bad. mitsubishi too.

VTEC is not used in LeMans, Formula1 or JGTC.

rotaries dont really need vtec, because they aren't inefficient enough to need something as such to make it more efficient - power-wise that is. mazda stuck on extra exhaust ports and the power just went up to 177kw for the renesis, which isnt too bad. aside from that, mazda claimed that it was relatively unchanged from the old 13b non turbos. can anyone say that honda could do such a minimal change and gain a big boost? with just an exhaust system alone? because thats what mazda did.

Rotaries CAN'T use vtec because rotaries DO NOT have cams and valves.
The Renesis has side ports, so the ports can be bigger. The old 13B has ports on the peripheral (the curved wall). Also, the old-13B had 2 intake ports and 1 exhaust port. The Renesis has 2 intake and 2 exhaust. Sounds similar? Compare the power outputs of the old 3 valve D series (68kW) with the modern 2000 4-valve non-VTEC D-series (88kW). That's a big jump in power of 29%!

as to the motor part. as the rx8 completes 3 cycles with one revolution, the motor rotates at a third of the rate claimed on your tacho. so when you hit 9000rpm, your rotors are spinning at 3000rpm.
whereas with a piston motor, 8000rpm is 8000rpm. theres a difference in efficiency right there. less moving parts in rotary = more efficient too.

False, at 9000rpm, your crank is rotating 9000 times a minute.
Edit: Calculation mistake. 9000 combustions per minute per rotor, so that's 18000 combustions per minute at 9000 crank rpm. That is 4 times more than a 4-cyl piston engine. That's why a rotary drinks more fuel.

[SeverAMV]

False, at 9000rpm, your crank is rotating 9000 times a minute.

actually, surprisingly it isnt for the rotary motor. each rotor is rotating at 3000rpm when the tacho reads 9000rpm. it has 9000 combustions per minute, which is 18000 combustions per minute for a twin rotor. if it had 54000 combustions per minute, it would chug thru a tank in like 30 minutes.

i said that rotaries dont need vtec because they arent inefficient enough to need something as such to make it more efficient, wasnt referring to vtec alone, was saying it doesnt need something to alter how much air-fuel mixture goes in to boost power.

as for the power jump, was talking about the top end of the performance motor scale, but touche~

[aaronng]

actually, surprisingly it isnt for the rotary motor. each rotor is rotating at 3000rpm when the tacho reads 9000rpm. it has 9000 combustions per minute, which is 18000 combustions per minute for a twin rotor. if it had 54000 combustions per minute, it would chug thru a tank in like 30 minutes.

i said that rotaries dont need vtec because they arent inefficient enough to need something as such to make it more efficient, wasnt referring to vtec alone, was saying it doesnt need something to alter how much air-fuel mixture goes in to boost power.

as for the power jump, was talking about the top end of the performance motor scale, but touche~

LOL, calculation error on my part on the 54000 combustions. yes, the rotor spins at 3000rpm, but does 9000 orbitals per minute.

Well, Honda never released a 3-valve B series that I can use for comparison purposes. The next one down is the 1966 S800 2 valve per cylinder engine I guess....

[mqt55s]

would say having 3 ports for intake/exhaust give a performance boost.
and to maybe implement some kind of system to block of a port in the lower revs i.e run on 2 ports for intake/exhaust in lower revs/economy and 3 ports for more power?
variable port electronic control. VPEC just kicked in yo?

[d15z1SUX]

that would be a good idea. like variable port size. like it can open up during hard driving then you have a aggresive race port engine when u open the throttle up. i don't really know what im talking about. is it possible? haha.

[aaronng]

would say having 3 ports for intake/exhaust give a performance boost.
and to maybe implement some kind of system to block of a port in the lower revs i.e run on 2 ports for intake/exhaust in lower revs/economy and 3 ports for more power?
variable port electronic control. VPEC just kicked in yo?

According to wiki, Mazda's 1965 10A rotary supposedly had something similar. It had 2 intake ports, one of which was closed at low loads.

[silver_screen]

Incorrect, 4 stroke, 4 cylinder = 2 power strokes per revolution, not 4.
4 stroke, 6 cyl = 3 power strokes/revolution
4 stroke 8 cyl = 4 power strokes/revolution

Each cylinder has 1 power stroke every 2 revs.

im actually 100% correct.

[Vinnie]

can we leave out the 'f1 technology' argument... the brochure for my accord claimed it has nsx technology jus coz it has vtec

[Muzz]

im actually 100% correct.

Incorrect again.

a 4 cyl is 1/4 each.. so every 1/4 of the crank turn, theres a power stroke.

What you are saying here, is that a 4 stroke 4 cylinder has 4 power strokes per revolution.

You could directly translate that to each cylinder having a power stroke in one complete revolution, correct??

So let me ask you this.
If all the cylinders fire within one revolution, do all 4 cylinders fire again the next revolution, or does each alternate revolution have no power strokes??

See whats wrong here?
Your saying each cylinder has a 180 degree power stroke within every 360 degrees of rotation

Intake, compression, power, exhaust, 4 strokes, 4 strokes which add up to 720 degrease rotation.

It takes 2 rotations of the crank for each cylinder to have a SINGLE power stroke. Agree????

So if all 4 cylinders fire in one rotation, then there must be no power strokes the next rotation, as each cylinder needs 2 full rotations to complete a power stroke.
^^Is this what you are trying to say

0 degrease
cyl 1, power stroke
cyl 2, intake stroke
cyl 3, exhaust stroke
cyl 4, compression stroke

180 degrease
cyl 1, exhaust stroke
cyl 2, compression stroke
cyl 3, intake stroke
cyl 4, power stroke

360 degrease
cyl 1, intake stroke
cyl 2, power stroke
cyl 3, compression stroke
cyl 4, exhaust stroke

540 degrease
cyl 1, compression stroke
cyl 2, exhaust stroke
cyl 3, power stroke
cyl 4, intake stroke

720 degrease, Back to the start:
cyl 1, power stroke
cyl 2, intake stroke
cyl 3, exhaust stroke
cyl 4, compression stroke

As you can plainly see, there arnt 4 power strokes per rotation. There are 4 power strokes per 2 revolutions, which means there are 2 power strokes per revolution

Still dissagree??