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Here's some food for thought too! If anyone is looking into getting a JDM Rotary, DO NOT modify it without having it tuned. The Japanese ECU is programed to run on 104 Octane fuel and not on 91(and some places 94) like we have here. Adding the slightest mods to the car(open intake, down pipe and larger exhaust) will cause it to run lean and detonate. On the other hand, USDM models, can handle and forgive a little more.
 

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I4MX6;2270820 EDIT. Just to add. This is the EXACT reason why the 787B LeMans car was no longer allowed in racing events. Better longevity and mileage then all other cars on the course. Less time in the pits meant more wins. That's only part of it I'm sure said:
Hate to dissagree on this point but it's been well documented that the Mazda lemans technicians were very aware of the rotarys tendancy to burn much more fuel per lap than the piston cars and that that issue had to be regulated closely to keep the cars from falling behind due to excessive pit stops.
 

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Hate to disagre on this point but it's been well documented that the Mazda lemans technicians were very aware of the rotarys dendancy to burn much more fuel per lap than the piston cars and that that issue had to be regulated closely to keep the cars from falling behind due to excessive pit stops.
Strange, I have heard the exact opposite. Even had video of commentary confirming my statement. Oh well, thanks for clarifying.
 

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I can recall hearing it from the mouth of an actual team member on a broadcast interview, he stated that by the time of the winning race they were very aware of tha cars consumption issue and tha techs and drivers had to be very careful about monitoring fuel level and the drivers specificaly had do watch how they used the gas pedal to keep it in check.

In the end they were successful obviously but the rotary at full tilt is a relatively thirsty motor even compared to a field of all out race motors.
 

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Discussion Starter #47
I guess driving a rotary balls out brings more meaning to the term 'hauling ass, sucking gas' LOL.
 

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In the end they were successful obviously but the rotary at full tilt is a relatively thirsty motor even compared to a field of all out race motors.
Yeah, the thing everyone forgets, is that the rotary has lousy thermal efficiency thanks to a combustion chamber shape which has a high surface area to volume ratio...
However it has a high mechanical efficiency thanks to having no valve train and low rotating mass...

So...while Rotary engines are thirsty, they will be more so at low revs, where the combustion gasses spend more time exposed to the cooling system, and to make matters worse, owing to the high power density the cooling system needs to remove alot of heat quickly, but at low revs contributes to lower efficiency.

A rotary engine has obvious advantages in the aviation industry where constant RPM and low weight are higher priorities...in that situation they will be much better than piston....in a car where th engine is a low % of the overall weight there is less overall gain.

Thats also why turbine cars never took off....the chysler turbine car of 1964 might have had a mainstream future otherwise.

Sports cars where people dont give a fuck about fuel economy and are more likely to want to look after the engine is more where the rotary engine lies in the auto industry
 

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Thats some good info chief, I have been thinking about potential benifits of thermal coatings for rotaries. But the only surface I can be sure of being viable are the rotor faces. Bit it's the outer and side housings that proabably contribute most to lost heat.
 

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Engine is a little bit more torn down than that, but definitely not short block status. Gonna rebuild it myself. Quite a ways away, but I can't wait to finish her. :jump:
 

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Engine need a rebuild internally or just a reassembly?
Pulled it out of a junk yard with 150k mi.;)

It was the only one in a junk yard, still with engine(Trans gone) for hours around that didn't want $500+ for a possibly non running engine. I got it for $100 there. I hope there's not too much damage, but oh well if it is. I hope at least half the engine is still rebuildable, but I'm expecting one of the housing's to be done for.
 

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Just thought I would post these up ;)

There was a certain member on this forum who boldly claimed that "NO ROTARY CAN EVER MAKE A THOUSAND HORSEPOWER OR MORE" and that "EVEN A 20B IS LIMITED TO ABOUT 700HP MAXIMUM"
 

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LOL! Mind saying his name?

Even though these massive numbers are attainable from Rotary engines, they're ultimately mostly useless. A well suited 450WHP RX-7 can easily keep up and BEAT other cars that have upwards of 700HP. A 700WHP 20B powered FD can VERY easily hang with a 1100HP Supra. "Power Efficiency > Power" :D
 

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Discussion Starter #55
A 700WHP 20B powered FD can VERY easily hang with a 1100HP Supra. "Power Efficiency > Power" :D
Not to mention the power to weight ratio and the fact that Supras are PIGS. They suck more gas then anything I have seen, besides maybe the new Evo Xs.
I think I might no who ls six is talking about. Wasn't that member banned... wait we can't talk about that.:cool:
 

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LOL! Mind saying his name?

Even though these massive numbers are attainable from Rotary engines, they're ultimately mostly useless. A well suited 450WHP RX-7 can easily keep up and BEAT other cars that have upwards of 700HP. A 700WHP 20B powered FD can VERY easily hang with a 1100HP Supra. "Power Efficiency > Power" :D
Thats true ;) not to mention they are able to maintain a broad curve even at such high peak output, the peak numbers really dont tell the whole story with a rotary. Other small displacement engines lose all reasonable streetability at 6-700+ whp but the rotarys (if you dont mind the sound and high idle) still drive nice and can be well behaved on the street.


Not to mention the power to weight ratio and the fact that Supras are PIGS. They suck more gas then anything I have seen, besides maybe the new Evo Xs.
I think I might no who ls six is talking about. Wasn't that member banned... wait we can't talk about that.:cool:
I dont recall the name but he's well known and still around I believe. It happened on an RX7 thread started by Mazdaspeed feen and he couldnt drop the wholr LSx swap thing. My rational defense of the rotary earned my a nomination as mx6.com man of the year by feen lol.

Supras are dyno queens and drag cars for a reason ^ A hotrod mag featured a 69 camaro with a 2JZ swap making around 800 hp, sure it was fast but the gears had to be so short that you never actualy let the clutch all out on a 1/4 run.
 

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Discussion Starter #57
Horsepower wins brags, Torque wins drags. Many times it's found that peak numbers don't tell the whole story. If you got a good steady torque line behind that horsepower line on the dyno, then you're in good shape.
 

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Horsepower wins brags, Torque wins drags. Many times it's found that peak numbers don't tell the whole story. If you got a good steady torque line behind that horsepower line on the dyno, then you're in good shape.
That's true, but the RX-7 is not a drag car, it's a track car. A good track car doesn't need a lot of torque, but horsepower is more important. Perfect example: F1 cars. they have roughly 700-750HP but only 200ft-lbs of torque. Yet they FLY by at speed exceeding 300 KM/h (185MPH).



EDIT: Feelin' better BTW?
 

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Discussion Starter #59
Correct it is not a drag car. But like I was trying to say, it's not how much but where it is in the powerband and how it is used. A drag car lives for highend peaky power numbers, while a road racing(ie: time attack) car goes faster with lower horsepower numbers as long as the powerband is smooth and flat. Yes they still need some top end pull, but acceleration and pull out of a corner are much more important.

And yes I am. Thank you for asking, man. four days of Swine hell! I'm feeling better just doing something today, plus I think I'm starting to pull out of it.
 

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I'll just leave this here....








 
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