2012 Mazda RX-7
09-12-2010, 08:27 PM
#101
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Healthy ignition, healthy O2 sensors, a tune and fuel trims that aren't garbage, a healthy cat or no cat, and compression that is above average.
Anyone who can't post 18-20 city and 22-25 highway has something wrong with one or more of the above. I know of a few members that are up to ~28mpg. Oldragger nearly hits 30mpg with his S2 transmission, S1 rear gear, and Pettit supercharged.
But that isn't the point I was trying to make. I was simply refuting the "Two, if it got 25MPG at it's current Horsepower rating. Neither of those scenario's are in place or even close to being a reality". Regardless of even if just a handful of people are getting past this, it makes it a very real possibility, and the reality of several people.
People have a misconception that the rotary = terrible gas mileage, when what goes through their head is either A) I need lots more power for that mileage or B) A 1.3L piston engine car gets better mileage than this.
The reality is that power is exactly contrary to MPG. Power is a direct result of burning fuel, and assuming that all manufacturers aim for the same point, burning approximately 1 part of fuel for 13 parts of air. This mixture makes power the same way in every engine. You can't have power without burning the fuel. A 300hp car can spend it's life neutered to ~100hp and get good gas mileage, or it can use it's 300hp and get 8mpg. You simply can't get 30+mpg while using 300+ hp.
It seems obvious, but it's a point that many forget.
B is clearly wrong, but time and again people link the mileage to 1.3L, forgetting that a piston 1.3L makes....80hp?
And then there is the whole slew of people who review sports cars that completely ignore mentioning mileage, but get to the 8 and it's bash on the mileage every chance you get.
Then they move on to review an SUV and applaud the 15mpg or 18mpg.
If you buy a car for fun, ignore the mileage. If you buy a car for mileage, enjoy the mileage.
I spend less in gas each year, even pumping premium, than I did for any of my prior cars, which include 4 corollas, a geo tracker, and a dodge caravan.
You have 1 valid point, in that if the RX-8 did have EPA values higher than it does, or if people didn't have so much fun driving them that they rarely spend time in the efficiency zone, then they probably would sell more RX-8s. Yet another case of the unwashed masses valuing stuff and making decisions for the wrong reasons without actually learning why and getting stuff right. But a mass of people making faulty assumptions with faulty information doesn't mean that something is impossible.
Rotaries have a lower volumetric efficiency than pistons, therefore 2 otherwise equivalent engines and powertrains in a controlled environment, the piston engine will be able to post a higher MPG than the rotary. That doesn't mean that high mileage rotary engines are possible. The Frazier-Nash Namir is one example. A tiny turbocharged rotary engine with a 0-60 of 3.X seconds, top speed of 190+, and 97mpg. WEIGHT is the biggest factor, pairing it with a hybrid is the 2nd biggest gain possible.
When people talk about power, they talk about low gears, high acceleration, high speed, etc. They don't talk about cruise and top "over-drive" gear. When people talk about mileage, they talk about cruise "over-drive" gear, not acceleration or high speed. Cruising only uses ~40 grams of air per second in our RX-8, which is roughly 40whp. What if they had a small series hybrid engine putting out ~50-60hp slaved to 6th gear so that you have the rotary enjoyment of 1st through 5th, and when you shift to 6th it engages the series hybrid and your mileage shoots through to roof. 40+, if not 60+ mpg is then possible without an expensive drivetrain and masses of weight, or even any extra batteries.
Think outside of the box. Don't stay stuck in the box that others have drawn.
Anyone who can't post 18-20 city and 22-25 highway has something wrong with one or more of the above. I know of a few members that are up to ~28mpg. Oldragger nearly hits 30mpg with his S2 transmission, S1 rear gear, and Pettit supercharged.
But that isn't the point I was trying to make. I was simply refuting the "Two, if it got 25MPG at it's current Horsepower rating. Neither of those scenario's are in place or even close to being a reality". Regardless of even if just a handful of people are getting past this, it makes it a very real possibility, and the reality of several people.
People have a misconception that the rotary = terrible gas mileage, when what goes through their head is either A) I need lots more power for that mileage or B) A 1.3L piston engine car gets better mileage than this.
The reality is that power is exactly contrary to MPG. Power is a direct result of burning fuel, and assuming that all manufacturers aim for the same point, burning approximately 1 part of fuel for 13 parts of air. This mixture makes power the same way in every engine. You can't have power without burning the fuel. A 300hp car can spend it's life neutered to ~100hp and get good gas mileage, or it can use it's 300hp and get 8mpg. You simply can't get 30+mpg while using 300+ hp.
It seems obvious, but it's a point that many forget.
B is clearly wrong, but time and again people link the mileage to 1.3L, forgetting that a piston 1.3L makes....80hp?
And then there is the whole slew of people who review sports cars that completely ignore mentioning mileage, but get to the 8 and it's bash on the mileage every chance you get.
Then they move on to review an SUV and applaud the 15mpg or 18mpg.
If you buy a car for fun, ignore the mileage. If you buy a car for mileage, enjoy the mileage.
I spend less in gas each year, even pumping premium, than I did for any of my prior cars, which include 4 corollas, a geo tracker, and a dodge caravan.
You have 1 valid point, in that if the RX-8 did have EPA values higher than it does, or if people didn't have so much fun driving them that they rarely spend time in the efficiency zone, then they probably would sell more RX-8s. Yet another case of the unwashed masses valuing stuff and making decisions for the wrong reasons without actually learning why and getting stuff right. But a mass of people making faulty assumptions with faulty information doesn't mean that something is impossible.
Rotaries have a lower volumetric efficiency than pistons, therefore 2 otherwise equivalent engines and powertrains in a controlled environment, the piston engine will be able to post a higher MPG than the rotary. That doesn't mean that high mileage rotary engines are possible. The Frazier-Nash Namir is one example. A tiny turbocharged rotary engine with a 0-60 of 3.X seconds, top speed of 190+, and 97mpg. WEIGHT is the biggest factor, pairing it with a hybrid is the 2nd biggest gain possible.
When people talk about power, they talk about low gears, high acceleration, high speed, etc. They don't talk about cruise and top "over-drive" gear. When people talk about mileage, they talk about cruise "over-drive" gear, not acceleration or high speed. Cruising only uses ~40 grams of air per second in our RX-8, which is roughly 40whp. What if they had a small series hybrid engine putting out ~50-60hp slaved to 6th gear so that you have the rotary enjoyment of 1st through 5th, and when you shift to 6th it engages the series hybrid and your mileage shoots through to roof. 40+, if not 60+ mpg is then possible without an expensive drivetrain and masses of weight, or even any extra batteries.
Think outside of the box. Don't stay stuck in the box that others have drawn.
Last edited by RIWWP; 09-12-2010 at 08:33 PM.
09-12-2010, 08:45 PM
#103
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"Anyone who can't post 18-20 city and 22-25 highway has something wrong with one or more of the above. I know of a few members that are up to ~28mpg. Oldragger nearly hits 30mpg with his S2 transmission, S1 rear gear, and Pettit supercharged."
I call Complete BS. There is NO RX8 anywhere getting close to the Numbers you posted. Hence the FACT that it is no longer in production with no successor planned in the future. The EPA #'s are actually just a little generous and pretty close to actual. Which does not cut it in today's market.
I call Complete BS. There is NO RX8 anywhere getting close to the Numbers you posted. Hence the FACT that it is no longer in production with no successor planned in the future. The EPA #'s are actually just a little generous and pretty close to actual. Which does not cut it in today's market.
09-12-2010, 08:49 PM
#104
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I call Complete BS. There is NO RX8 anywhere getting close to the Numbers you posted. Hence the FACT that it is no longer in production with no successor planned in the future. The EPA #'s are actually just a little generous and pretty close to actual. Which does not cut it in today's market.
Neither my 8 nor any of the 8s that do get this mileage care whether or not you believe that they do. They still will.
Refusing to consider it just shows that you are short sighted, probably too heavily influenced by the public. Once you spend more time on the forums, you will see MPG threads pop up more, and more and more of us that get the mileage we do commenting that we do.
09-12-2010, 09:32 PM
#105
"Anyone who can't post 18-20 city and 22-25 highway has something wrong with one or more of the above. I know of a few members that are up to ~28mpg. Oldragger nearly hits 30mpg with his S2 transmission, S1 rear gear, and Pettit supercharged."
I call Complete BS. There is NO RX8 anywhere getting close to the Numbers you posted. Hence the FACT that it is no longer in production with no successor planned in the future. The EPA #'s are actually just a little generous and pretty close to actual. Which does not cut it in today's market.
I call Complete BS. There is NO RX8 anywhere getting close to the Numbers you posted. Hence the FACT that it is no longer in production with no successor planned in the future. The EPA #'s are actually just a little generous and pretty close to actual. Which does not cut it in today's market.
09-20-2010, 08:43 PM
#109
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09-20-2010, 10:28 PM
#110
Huge hole is huge
I got 28 Highway *Going 60 MPH the entire time.....while also driving down Dodge St. Omaha in Rush Hour traffic....*. It's doable, you just can't have a metal foot and keep the MPH at a decent level.
Even going 80 the entire way, I was able to muster 23-25 MPG. 23 MPG highway is LOW, so you people need to check some ****.
Even going 80 the entire way, I was able to muster 23-25 MPG. 23 MPG highway is LOW, so you people need to check some ****.
09-21-2010, 10:06 AM
#111
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I typically get 16-18 city because i have too much fun driving the car. I've done better when trying though. If i cared enough about mileage I could consistently get closer to 20.
It seems most of your handful of posts are trying to call bullshit on people that have been on the forum for much longer, have had their cars much longer, and are generally always helping new owners out. Stop making yourself look like an ***.
09-21-2010, 11:52 AM
#112
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It takes about 20 minutes for the renesis to start to become more efficient. Those on shorter commutes will never see the better numbers.
Fast driving is 14. Slow driving, using 6th gear in 20 mph zones, is 16.5-17. This is because the commute is only 10-15 miles, takes 15-25 minutes. I am only fully warmed up for a few minutes of the commute.
People are always happy to claim over 20, always citing their cross country trips or some ridiculous lengthy commute. Really not applicable to most experiences. And then have the gall to say something is wrong with others cars who can't get those numbers. hah!
Fast driving is 14. Slow driving, using 6th gear in 20 mph zones, is 16.5-17. This is because the commute is only 10-15 miles, takes 15-25 minutes. I am only fully warmed up for a few minutes of the commute.
People are always happy to claim over 20, always citing their cross country trips or some ridiculous lengthy commute. Really not applicable to most experiences. And then have the gall to say something is wrong with others cars who can't get those numbers. hah!
Last edited by User24; 09-21-2010 at 11:57 AM.
09-21-2010, 12:09 PM
#113
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Not that anyone cares, but I got 18.89mpg while hitting the PCH curves at ~7/10ths for a full tank. Have to calculate the total for the day on the additional.
I'll say it again, the people that insist that this type of mileage is impossible HAVE SOMETHING WRONG WITH THEIR CAR. It might be something correctable, it might not.
But if YOU can't get that mileage, it doesn't mean no one else can.
I'll say it again, the people that insist that this type of mileage is impossible HAVE SOMETHING WRONG WITH THEIR CAR. It might be something correctable, it might not.
But if YOU can't get that mileage, it doesn't mean no one else can.
09-21-2010, 02:33 PM
#114
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Ok back on track to 4th Gen Rx7. Depends on what Mazda does with the engine. With direct injection probably can get closer to 30.
1985 Rx7 was 29 highway.
1985 Rx7 was 29 highway.
Last edited by VashGS; 09-22-2010 at 02:42 PM.
09-21-2010, 06:45 PM
#120
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+1
It's a piston concept car Mazda made awhile back, it was in a Japan car magazine few years ago. I'll see if I can still find the spec of it....
It's mazda Kabura (マツダ 鏑), it was first displayed at 2006 Detroit motor show.
Details here: http://en.wikipedia.org/wiki/Mazda_Kabura
It's a piston concept car Mazda made awhile back, it was in a Japan car magazine few years ago. I'll see if I can still find the spec of it....
It's mazda Kabura (マツダ 鏑), it was first displayed at 2006 Detroit motor show.
Details here: http://en.wikipedia.org/wiki/Mazda_Kabura
Last edited by ShinkaEvo; 09-21-2010 at 06:55 PM.
That's hilarious!
09-22-2010, 08:38 AM
#124
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I'm gone. This is a typical car enthusiast forum. You have several (older) posters that chime in and tell you that your wrong with nothing to back it up with. They also offer no solution to the problem just BS. Back to the one undeniable fact. 99% of the RX8's on the road achieve terrible fuel economy. This fact is evident in the discontinuance of the product as well as future versions of it.
Now you can continue this discussion without me.
Now you can continue this discussion without me.
