Rotaries vs V8's

[stiddy]

try getting out of a boosted car into an n/a car..... lol your always waiting for something to happen..

[dansedgli]

I love the way the rotors sound at the drags with a dropped exhaust, there is an old mazda that runs 10.0 with a manual and it sounds absolutely horn when doing a burnout! Ill build one one day....

[4.9 EF Futura]

Originally Posted by stiddy

try getting out of a boosted car into an n/a car..... lol your always waiting for something to happen..

Lol! Signature worthy post right there!

[stiddy]

Originally Posted by dansedgli

Ill build one one day....

Do it, you know you want to.. in something like an R100..

[rag top]

I found the fuel economy was the same for a stock 13B S4 n/t as a VL V8 commie.
The rotor was fun to drive, but expensive on some non mechanical parts.

[Psycho Chicken]

Ahhh scrotaries, go hard but sound like a whipper snipper on roids.

[Paul_au]

Any engine that makes big power will use a lot of fuel. I have owned many of both v8s and rotors from na to turbo. They use around the same in general when I compare the ones I have had.

The more power you make, the more fuel you use. They both are around the same in general I beleive from personal experience.

I would say a stock rotor would use a little less than a stock v8 (of the same year) though but worked around the same NA.

P.S. Rotors are reliable when built correct and NOT over-revved. They were terribly unreliable when they came out around late 60s in production cars here but then again so was the piston engine when it came out.

Rotors have not had half the time as piston engines have had but they are reliable these days (personal experience). Most people seem to think they rev to 8000+ when stock or slightly worked....THEY DONT! most of them are actually recommended to be revved BELOW 6500rpm to keep reliable. I can tell you that you can generally over-rev them a little and maintain reliability unlike v8s though. Over rev v8s and springs go and much more from there. Over rev a rotor and the rotors start to bounce as such and the break apex seals but they can bounce for longer and more often than springs can handle in piston motors.

I like both (love both) and have had both. They both have good and bad points but rotaries are not unreliable these days at all. If you think they are then you have been told crap or been ripped off by a dodgy mechanic or just plain bad luck (never seen the bad luck part though - being nice).

My old rotor was 1.3 litre and made just under 270Hp at flywheel and had no gas, no turboes and no s/c. Sold it after 3 years and 88000kms and had great compression and ran like new! This was a very worked motor obviously and big output for the size and this is almost the most unreliable type and so I dont think it was unreliable. Burnout comp and drags time after time and still going great after 88000 kms... (guy bought it and rolled it and died - small car - big power - locked diff - inexperience - rain)

Paul

[aimzes]

had a mate that owned an RX3 that did 11s, or 12s... the car ended up being a bit of a nightmare so he sold it. i think it used to go through 25-30L/100km... could be thinking of another rotor i know.

but that car was great. just starting her up in the shed was fun... lol it sat there with that typical rotor WAHWAHWAHWAHWAH! ahaha.

give me an RX2.

[Rodp]

Despise the scroat. They were much popular though I don't ever recall seeing many turbocharged ones in the late 80's and early 90's when I used to cruise around in my GT.

The bridgeported ones would be great if your name was Bob. Bob bob bob bob bob bob.

I guess it wasn't so much the car (apart from the most annoying exhaust note on the planet) but the attitudes of the drivers of most of them that would often chase me down and rip into me at the lights about how their 1.3l could blow away my dinosaur.

Twas funny. After one of them couldn't (and by a BIG margin), he complained the difference was the fact that he had a passenger. I was ~110kg. Him and his passenger were miniscule, together they would have barely made it to 100kg.

I had a mate who recently sold his scroat and I've seen him pull wheelstands in it and clock 10's rather easily. I certainly respect the performance you can wring out of them.

[jabba]

I owned a series 4 RX7 Turbo. Nice little car and handled very well. On the highway it was very economical if you sat on 100kay, over that and it suck the juice. City driving, it's as bad as a V8, very thirsty... The new RX8 is supposed to be more economical then the old.

I hate the sound of a bridge ported rotary. Sounds like a duck farting.....

[FJ20ET]

A lot of people confuse rotors with crazy fog but crazy fog is definately more annoying.
My rx4 used about the same fuel as a small six If ikept off the secondaries but chewed fuel when I was chewing v8s.(13B mild port, mechanical secondries, 2.5 in exhaust).
In the end it took out a brand new VK commodore when it wouldnt stop.......crunch.

[MITCHAY]

Originally Posted by VY18s

I like Rotaries

But give me a V8 or possibly a 6 over one any day though.

Rotaries arent the most reliable engines.

I've heard they are one of the more reliable engines because they have less mechanical parts therefore less to go wrong.

[nang3]

after driving an RX8 and GT i would take the GT HANDS DOWN !!!

but an older rotary i.e. Rx3/7 etc bombed off its tits is a weapon

[gozza]

i don't like the rx8's

[XD 351 Ute]

Originally Posted by Paul_au

Any engine that makes big power will use a lot of fuel. I have owned many of both v8s and rotors from na to turbo. They use around the same in general when I compare the ones I have had.

The more power you make, the more fuel you use. They both are around the same in general I beleive from personal experience.

I would say a stock rotor would use a little less than a stock v8 (of the same year) though but worked around the same NA.

P.S. Rotors are reliable when built correct and NOT over-revved. They were terribly unreliable when they came out around late 60s in production cars here but then again so was the piston engine when it came out.

Rotors have not had half the time as piston engines have had but they are reliable these days (personal experience). Most people seem to think they rev to 8000+ when stock or slightly worked....THEY DONT! most of them are actually recommended to be revved BELOW 6500rpm to keep reliable. I can tell you that you can generally over-rev them a little and maintain reliability unlike v8s though. Over rev v8s and springs go and much more from there. Over rev a rotor and the rotors start to bounce as such and the break apex seals but they can bounce for longer and more often than springs can handle in piston motors.

I like both (love both) and have had both. They both have good and bad points but rotaries are not unreliable these days at all. If you think they are then you have been told crap or been ripped off by a dodgy mechanic or just plain bad luck (never seen the bad luck part though - being nice).

My old rotor was 1.3 litre and made just under 270Hp at flywheel and had no gas, no turboes and no s/c. Sold it after 3 years and 88000kms and had great compression and ran like new! This was a very worked motor obviously and big output for the size and this is almost the most unreliable type and so I dont think it was unreliable. Burnout comp and drags time after time and still going great after 88000 kms... (guy bought it and rolled it and died - small car - big power - locked diff - inexperience - rain)

Paul

A very good post on this issue, you put into words what I was thinking, good stuff.

I was a rotor hating type, until my friend sat me down one day & explained how they work, and the design, etc, etc.
Certainly opened my eyes for sure, and now they have my respect for issues as well as, and other than performance.

Must have had some effect on me, I've had 2 of the little critters so far.

Anyone here that does not understand them, but does have a mechanical interest, should take a close look, you'll be surprised!

Regarding the original post, I suppose it depends on what you're comparing exactly; whether stock or modified.

From my experiences, they are probably on a par at either specification, but I would go as so far to say that my old 12A powered RX7 used far less fuel than what my 351 XD does.
Both of these vehicles were/are standard, and retain all standard accessories, with the exception of the exhaust.

I do know through my friends car, that a severely ported or modifed rotary will go through plenty of fuel, and this is prettywell the same as the eight.

As always, it comes back to what it is, and mostly, how it is driven.

Reliability in our case has never been an issue, we've had no engine related mechanical failure with our cars, whether standard or modified.

Some have mentioned their dislike of the noise of a rotary, but this again comes back to set-up & the way it is driven.
I reckon that I have heard just as many horrible sounding eights as I have rotaries, Pre-pollution 308 anyone???

A well set-up, well tuned, and well driven rotary in the majority of cases is an equal of a V8 in my opinion, and they are getting quicker!!

Ed

[gozza]

ive eaten slightly modified v8 vr utes in the stock 5spd 13b(well not eaten but beat them heh)

[eb91xr6]

I Hate them. had a mate own and he spent heaps on his keeping it running, any thing that could go wrong went, he was always complaining about fuel, it was a S4 non turbo, my 6c falcon gave it a run

heap of

[chevypower]

Rotaries tend to use more fuel, but they can go hard without spending too much on them. I prefer V8s for every day driving, but if you want to build a really cheap rocketship, rotaries arent a bad option. It was interesting when a girl from Alabama I went to the Melb motorshow with, told me her parents back home were going to buy an RX-8, but decided to get an F150, because the RX-8 uses too much fuel. Don't know how ya toss up between those too, but there ya go.

[noosacuda]

Fuel use depends on your right foot! But to compare a Rotary to a V8 is like comparing a 2 Stroke to a 4 Stroke motorbike-one has revs,while the other has torque.

[Josho]

Originally Posted by XD 351 Ute

A very good post on this issue, you put into words what I was thinking, good stuff.

I was a rotor hating type, until my friend sat me down one day & explained how they work, and the design, etc, etc.
Certainly opened my eyes for sure, and now they have my respect for issues as well as, and other than performance.

Must have had some effect on me, I've had 2 of the little critters so far.

Anyone here that does not understand them, but does have a mechanical interest, should take a close look, you'll be surprised!

Regarding the original post, I suppose it depends on what you're comparing exactly; whether stock or modified.

From my experiences, they are probably on a par at either specification, but I would go as so far to say that my old 12A powered RX7 used far less fuel than what my 351 XD does.
Both of these vehicles were/are standard, and retain all standard accessories, with the exception of the exhaust.

I do know through my friends car, that a severely ported or modifed rotary will go through plenty of fuel, and this is prettywell the same as the eight.

As always, it comes back to what it is, and mostly, how it is driven.

Reliability in our case has never been an issue, we've had no engine related mechanical failure with our cars, whether standard or modified.

Some have mentioned their dislike of the noise of a rotary, but this again comes back to set-up & the way it is driven.
I reckon that I have heard just as many horrible sounding eights as I have rotaries, Pre-pollution 308 anyone???

A well set-up, well tuned, and well driven rotary in the majority of cases is an equal of a V8 in my opinion, and they are getting quicker!!

Ed

Thanks Paul and Ed - that was the information I was looking for. Not like 3/4 of the idiots that went on talking about the engine noise.
Thanks, again.
Josh.