NOTA V6

That depends on the time and place.

I once had a kid with a 1st gen 12A RX-7 e-mailing me bragging about the NSX and new Celica he wasted. Not to mention the TT Supra. He claimed that they were not willing to go fast enough to win. D@mn punk street racers. Maybe the guy with the NSX values his car, his life and the lives of others enough to not have to exceed the top end of a stock 12A RX-7 to prove he is a better driver, or his car can go faster. :D To this kid it was all about *****, not power or skill...

Fiend

Hey, I just wandered over - nice site. Yall have some good discussion here. Just wanted to add a couple of coals to the fire. First, expanding on what Babylou was saying about backpressure, some useful info at the bottom of the first post (hell, it's all useful).
Second, something I haven't seen mentioned about the comparison between a the low torque engine with short gearing and high torque engine with long gearing is that if the comparitive ratios are 2:1 respectively, the low torque vehicle will be shifting twice as often, negating the speed advantage but upping the fun advantage. Of course, not everyone likes shifting all the time. Luckily, since the RX8 torque peaks so early, it won't have the problem the new Celly has of redlining and shifting into non-VVTI territory. I haven't driven one, but I can't imagine many more frustrating sensations.
VRRROOOOOMMM -shift- vrrr
Enjoy the club while it's small and yall know eachother!

Fiend

Sorry, I forgot sumthin and can't edit my post. The account must be too new. Anyways, my only other point is that in no way can heat be justified in a turbocharged engine. The focus of much of turbo designer Corky Bell's book Maximum Boost is how to avoid heat buildup. Heat is the main enemy of all turbocharged systems, the last gen RX7 especially!

RXRX

"Exactly! No valve-train thrashing and a good description there, guy. To those interested in the RX-8, take heed. The power curve feels like no other car. It will rev 'til it blows or is fuel-limited by the ECU. That's why it is so addicting. Like a Timex, it keeps going and going..... Rotaries rock! "-ToadMan

....THAT WAS WELL SAID!..thats the exact reason i loved the rx-7:D

SpreeGuy

actually, they will shift at the same time.

if we continue to use the 2:1 ratio, when the low torque engine reaches 9000 rpm, the 2:1 gearing will effectively reduce that rpm to 4500rpm. (therefore doubling the torque)

to compare, when the other engine reaches 4500 rpm, with a 1:1 gearing it will be rotating at 4500rpm. therefore shifting at the same time.

Note: i'm tired, and I hope that made sense.

enjoy

Thats very interesting information, thanks.

B-Nez

The moment has kind of passed, but for the 89-91 RX7 NA's, a certain amount of backpressure was necessary (if memory serves) to activate the 6-port actuators. Also, restriction creates velocity, so there is a balance to be had between a free-flowing (or wafting) exhaust stream, and one with some velocity. For cars that rely on backpressure effects to perform other functions (as in the above example), you have to be careful also.

NOTA V6

The back pressure for the 6PI you are speaking of is fed back through a tube in the exhaust. It is not exhaust back pressure as such, it is exhaust pressure fed back through the tube.

My understanding of the matter is that there is no performance use for backpressure. It is simply a byproduct of having restrictions on the exhaust, like emissions controls and mufflers...

B-Nez

That is true about the tube. I had forgotten about that. I've been rotor-less for almost 3 years, gettin a bit rusty.

Fiend

I thought it worked the other way around? I thought that a 2:1 relative gear ratio would double power but also comparitive revs (ie a 1:1 ratio produces 150 lb/ft but revs to 40 in first for example while a 2:1 ratio produces 300 lb/ft and redlines at 20). If it was the way you were saying, wouldn't that be free power, and everyone would use the shortest possible gears? I don't think the accounting department will pass that.

zoom44

man i hope rich doesn't see this. everybody go back and look at rich's posts about the gearing. there is a few links to articles that will explain alot.

SpreeGuy

that's true, IF both cars had the SAME redline.

lets assume both cars ran the same gearing. 1:1.

when the high torque car reaches redline (4500rpm) the car will be at 40

when the low torque car reaches redline (9000rpm) the car will be at 80, but because we put a 2:1 gear on the car it will actually be at 40.

therefore both cars shift at the same time.

Fiend

Got it now. I didn't understand your examples had different redlines-I thought the only difference was torque output and peak.

RX-pecting

I don't understand any of this torque stuff!! someone please explain it to me clearer

(just kidding)

I'm horrible...

2K4RX8

You guys are killin me. I have been a long time rotary owner, and have a passion for the motor.
You guys want torque like a 350Z, then you need to buy a car with a comparible sized motor. Where talking about a 1.3 Liter here. its 63% smaller than the 350Z's 3.5. It puts out 192 horsepower per liter! The last N/A rotary was rated at 160 horsepower which is 90 horsepower less than the RX8. I commend Mazda for such a feat, 90 horsepower out of the same sized motor without using forced induction. What I am trying to say is Rotarys are very small engines that put out monstrous horsepower figures(based on size) but are not torquers. I love rotaries not because of thier torque, but the horsepower they can deliver, and the passion of Mazda engineers. They know how it all started, and they wont let Fart ruin their passion. What other company's engineers would use their offtime to develop a car. If you have never driven a rotary powered car before, and want to race, then your are going to have to redline it. And yes, those buzzers are there for a reason, shift soon

Thank you for letting me get that out.

Fiend

Rotaries are definately smaller than piston engines, but what do yall rotorheads have to say about the idea that their size is way underrated? I've heard it said and written but not with proof or details.

n22lasing

What proof are you looking for? The fact that the 787B won the Le Mans in 1991? The fact that the Rotary engine has a 67% success rate at finishing the Le Mans races? No other Manufacturer can boast such credibility. Except for Honda, but they only had 3 cars race. I also have a 1985 RX-7 with 120K miles on it, not ONE problem! I am sure there are plenty of other real world situation that prove the credibility of the rotary engine. Many of other people here can share their ideas too.

NOTA V6

I think you missed it n22lasing.

I agree with Fiend. The size of the rotary and the power and simplicity thereof is terribly underrated. After explaining the rotary to the previously unenlightened, I often get the response "I wonder why all cars don't have these?"...

People need to stop underestimating and underrating the rotary. And that's all I have to say about that.

:D

n22lasing

Aw man! I get it now :p

stan11003

NOTA V6

The reason why more cars aren't rotarys is the same reason more cameras aren't polaroid, Patents, Patents and more patents.

Patents eventually run out but by that time the patent holder has made more improvements to thier tech so it doesn't make sense to compete with them.

NOTA V6

Actually several other auto manufacturers have had the rights to develop their own rotaries over the years. The '70 gas crunch effectively ended all efforts in the US market. The rotary has only been in automotive use since the '60s, so relative to the piston engine, it is still a young engine developmentally speaking.

http://www.monito.com/wankel/history.html
http://www.monito.com/wankel/manufacturers.html
http://www.monito.com/wankel/motorcycles.html
http://www.monito.com/wankel/vehicles.html
http://mrmazda.members.atlantic.net/link_car.html (at the top)

So it's more bad timing and planning than copyrights and development IMHO.

BTW, that was the response I'd get after explaining things, not my own question. :D

zoomzoomlover

How much would a turbo help with torque? How about supercharger? Im a noob at this kind of stuff, so please help!!

nycgps

iTrader: (1)

Omg holy thread revival !!!!

gfailure

RIWWP

iTrader: (2)

Closed.

I am pretty sure this has been answered at least once in the past 10.5 years.