Miles to TANK, S4 ONLY
01-11-13, 02:35 AM
#26
Possibly the highway has a tailwind and/or is slightly down hill? Were the trips back to back?
You can also get some bias from when the fuel pump turns off because if it turns off late at the start fill up and early on the end fill up then you can get an elevated number. This will be clear though if the next tank gives much worse mileage.
30 is my personal goal but I don't know if my car is capable. I'm thinking I'll go over the mountain pass and engine-off coast the whole way down. We'll see what happens...
You can also get some bias from when the fuel pump turns off because if it turns off late at the start fill up and early on the end fill up then you can get an elevated number. This will be clear though if the next tank gives much worse mileage.
30 is my personal goal but I don't know if my car is capable. I'm thinking I'll go over the mountain pass and engine-off coast the whole way down. We'll see what happens...
01-11-13, 10:23 AM
#27
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01-11-13, 10:29 AM
#28
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S5's have 18.5 gallon fuel tanks, aka 70 litres (I'm Canadian, eh)
I know this is about s4's but I find it odd that I achieved 31mpg on the highway once (300kms and filled up for 23 litres or 187.5 miles and filled up 6.1 gallons) and got 30mpg another trip, same highway but I could not for the life of me get more than 300-350kms (220 miles at best) before my fuel light is on and even then I still drive for a bit before filling up in the city with a bit of highway which equates to about 13 mpg which is I assuming I have 1.5 gallons left in the tank.
Even if I drive slow and barely rev past 3-3.5k I still achieve 12-14 mpg city/highway mix/ What could cause such terrible city mileage but great highway mileage. I've changed the plugs and the fuel filter already and it can't be the thermostat since I'm almost never driving fast enough in the city for it to be in closed loop. I'm never in 5th gear, sometimes if I'm lucky.
All this in my 1991 N/A with only 105,000kms
I know this is about s4's but I find it odd that I achieved 31mpg on the highway once (300kms and filled up for 23 litres or 187.5 miles and filled up 6.1 gallons) and got 30mpg another trip, same highway but I could not for the life of me get more than 300-350kms (220 miles at best) before my fuel light is on and even then I still drive for a bit before filling up in the city with a bit of highway which equates to about 13 mpg which is I assuming I have 1.5 gallons left in the tank.
Even if I drive slow and barely rev past 3-3.5k I still achieve 12-14 mpg city/highway mix/ What could cause such terrible city mileage but great highway mileage. I've changed the plugs and the fuel filter already and it can't be the thermostat since I'm almost never driving fast enough in the city for it to be in closed loop. I'm never in 5th gear, sometimes if I'm lucky.
All this in my 1991 N/A with only 105,000kms
01-11-13, 02:59 PM
#29
Possibly the highway has a tailwind and/or is slightly down hill? Were the trips back to back?
You can also get some bias from when the fuel pump turns off because if it turns off late at the start fill up and early on the end fill up then you can get an elevated number. This will be clear though if the next tank gives much worse mileage.
30 is my personal goal but I don't know if my car is capable. I'm thinking I'll go over the mountain pass and engine-off coast the whole way down. We'll see what happens...
You can also get some bias from when the fuel pump turns off because if it turns off late at the start fill up and early on the end fill up then you can get an elevated number. This will be clear though if the next tank gives much worse mileage.
30 is my personal goal but I don't know if my car is capable. I'm thinking I'll go over the mountain pass and engine-off coast the whole way down. We'll see what happens...
I just wish I drove highway more often, aha. There was one point where I was doing 170-180kmph for a nice amount of time playing around with an F150 who felt like driving fast as well as some van and I barely even noticed my gas gauge move, I was surprised. That's probably because I barely left 4th and 5th gear. But this isn't when I got 30+ mph, aha. Since 90% of my driving is city, it's a pain driving a car that gets 11-13mpg in a town that gas costs 1.22$ - 1.30$ a litre (4.60$ - 4.90$ a gallon). When I was living in the Sault gas was 1.399 (5.30$) most of the time. Hence why I'm trying to buy a Miata.
Last edited by ryan2949; 01-11-13 at 03:03 PM.
01-11-13, 04:11 PM
#30
Gasoline engine are most efficient at high load, and this is even more true for rotaries. Driving fast on the freeway may have alot of air drag, but it's being made up for because the engine is operating very efficiently (in terms of power output per unit fuel)
I always shift fairly high in the rpm's for this reason. People always say to shift as low as possible, but that's just silly. You have to get up to speed somehow and working the engine hard at a more efficient operating range for a shorter amount of time is going to be better then grandma shifting at 3k making the engine operate at a less efficient rpm for a longer amount of time.
You don't want to accelerate hard into a stop though, and that's why people think shifting low is better i think.
01-11-13, 08:30 PM
#31
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absolutely nothing to be honest. I'm a pretty gas conscious driver most of the time though, I coast alot and try to predict stops ahead of me. I seem to get the best mileage when I don't care.
Gasoline engine are most efficient at high load, and this is even more true for rotaries. Driving fast on the freeway may have alot of air drag, but it's being made up for because the engine is operating very efficiently (in terms of power output per unit fuel)
I always shift fairly high in the rpm's for this reason. People always say to shift as low as possible, but that's just silly. You have to get up to speed somehow and working the engine hard at a more efficient operating range for a shorter amount of time is going to be better then grandma shifting at 3k making the engine operate at a less efficient rpm for a longer amount of time.
You don't want to accelerate hard into a stop though, and that's why people think shifting low is better i think.
Gasoline engine are most efficient at high load, and this is even more true for rotaries. Driving fast on the freeway may have alot of air drag, but it's being made up for because the engine is operating very efficiently (in terms of power output per unit fuel)
I always shift fairly high in the rpm's for this reason. People always say to shift as low as possible, but that's just silly. You have to get up to speed somehow and working the engine hard at a more efficient operating range for a shorter amount of time is going to be better then grandma shifting at 3k making the engine operate at a less efficient rpm for a longer amount of time.
You don't want to accelerate hard into a stop though, and that's why people think shifting low is better i think.
01-13-13, 08:04 PM
#34
Driving RX7's since 1979
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LOL Man I needed to light a match to deal with the smell of all the bull **** mileage claims being thrown around on this thread.
I've been driving RX7's as long as there have been RX7's. I've owned and sold more RX7's than I can remember starting with my carbureted '79 through my DD SFI S4 Vert now TurboVert, and of course my EFI 91's. I've driven them long distances from LA to Seattle and back and most recently LA to Dallas, TX and back. Staying on cruise control, I've gone through tanks where almost 100% was 50 mpg, and then 5 mph increments up and down from there. I'm **** about keeping my engine in good tune, and keep tire pressures at the high end (which reduces rolling resistance, and I've had my speedo professionally calibrated to insure measured miles are accurate. I've run so many times fool fuel to engine sputtering due to tank essentially empty (keeping a full 2 gallon gas can in the car when doing these maximum range tests.
And THE most I've ever achieved is in a 16.5 gallon S4 tank has mostely been 260-280 miles (although I did kiss 300 miles once driving across the flat midwest plains near 100% of that tank of gas burned while on 50 mpg cruise control). Maximum MPG, never much more than 18mpg and most common 15-16.5. So anyone that claims 300 miles+ on a stock 16.5 gallon S4 tank running a wankle engine, it would be appropriate to light a match right away to deal with the smell of bull ****. That, or something is very wrong with what the calibration of the speedo (most likely caused by running smaller than stock diameter tires that would cause higher than actual mileage counting).
I've been driving RX7's as long as there have been RX7's. I've owned and sold more RX7's than I can remember starting with my carbureted '79 through my DD SFI S4 Vert now TurboVert, and of course my EFI 91's. I've driven them long distances from LA to Seattle and back and most recently LA to Dallas, TX and back. Staying on cruise control, I've gone through tanks where almost 100% was 50 mpg, and then 5 mph increments up and down from there. I'm **** about keeping my engine in good tune, and keep tire pressures at the high end (which reduces rolling resistance, and I've had my speedo professionally calibrated to insure measured miles are accurate. I've run so many times fool fuel to engine sputtering due to tank essentially empty (keeping a full 2 gallon gas can in the car when doing these maximum range tests.
And THE most I've ever achieved is in a 16.5 gallon S4 tank has mostely been 260-280 miles (although I did kiss 300 miles once driving across the flat midwest plains near 100% of that tank of gas burned while on 50 mpg cruise control). Maximum MPG, never much more than 18mpg and most common 15-16.5. So anyone that claims 300 miles+ on a stock 16.5 gallon S4 tank running a wankle engine, it would be appropriate to light a match right away to deal with the smell of bull ****. That, or something is very wrong with what the calibration of the speedo (most likely caused by running smaller than stock diameter tires that would cause higher than actual mileage counting).
01-14-13, 02:12 AM
#35
Actually, now that I think of it... My speedo is off. At 110kmph I'm actually doing 100kmph verified by GPS and having a friend drive 100 in his vehicle and I was behind doing 110kmph. So if I am getting 350 kms per 62-63 litres or about 13mpg, does that mean I'm actually getting worse mileage because my speedo is faster? I'm also running 205/55/16 (stock turbo size) on my S5 N/A.
I'm assuming you're generalizing S4's because if I was able to drive 190 miles and filled up 6 gallons that clearly shows I got an average of 30+ mpg.
EDIT: When you say 50mpg cruise control, do you mean 50MPH? Aha.
I'm assuming you're generalizing S4's because if I was able to drive 190 miles and filled up 6 gallons that clearly shows I got an average of 30+ mpg.
EDIT: When you say 50mpg cruise control, do you mean 50MPH? Aha.
01-14-13, 02:26 AM
#36
LOL Man I needed to light a match to deal with the smell of all the bull **** mileage claims being thrown around on this thread.
I've been driving RX7's as long as there have been RX7's. I've owned and sold more RX7's than I can remember starting with my carbureted '79 through my DD SFI S4 Vert now TurboVert, and of course my EFI 91's. I've driven them long distances from LA to Seattle and back and most recently LA to Dallas, TX and back. Staying on cruise control, I've gone through tanks where almost 100% was 50 mpg, and then 5 mph increments up and down from there. I'm **** about keeping my engine in good tune, and keep tire pressures at the high end (which reduces rolling resistance, and I've had my speedo professionally calibrated to insure measured miles are accurate. I've run so many times fool fuel to engine sputtering due to tank essentially empty (keeping a full 2 gallon gas can in the car when doing these maximum range tests.
And THE most I've ever achieved is in a 16.5 gallon S4 tank has mostely been 260-280 miles (although I did kiss 300 miles once driving across the flat midwest plains near 100% of that tank of gas burned while on 50 mpg cruise control). Maximum MPG, never much more than 18mpg and most common 15-16.5. So anyone that claims 300 miles+ on a stock 16.5 gallon S4 tank running a wankle engine, it would be appropriate to light a match right away to deal with the smell of bull ****. That, or something is very wrong with what the calibration of the speedo (most likely caused by running smaller than stock diameter tires that would cause higher than actual mileage counting).
I've been driving RX7's as long as there have been RX7's. I've owned and sold more RX7's than I can remember starting with my carbureted '79 through my DD SFI S4 Vert now TurboVert, and of course my EFI 91's. I've driven them long distances from LA to Seattle and back and most recently LA to Dallas, TX and back. Staying on cruise control, I've gone through tanks where almost 100% was 50 mpg, and then 5 mph increments up and down from there. I'm **** about keeping my engine in good tune, and keep tire pressures at the high end (which reduces rolling resistance, and I've had my speedo professionally calibrated to insure measured miles are accurate. I've run so many times fool fuel to engine sputtering due to tank essentially empty (keeping a full 2 gallon gas can in the car when doing these maximum range tests.
And THE most I've ever achieved is in a 16.5 gallon S4 tank has mostely been 260-280 miles (although I did kiss 300 miles once driving across the flat midwest plains near 100% of that tank of gas burned while on 50 mpg cruise control). Maximum MPG, never much more than 18mpg and most common 15-16.5. So anyone that claims 300 miles+ on a stock 16.5 gallon S4 tank running a wankle engine, it would be appropriate to light a match right away to deal with the smell of bull ****. That, or something is very wrong with what the calibration of the speedo (most likely caused by running smaller than stock diameter tires that would cause higher than actual mileage counting).
Interesting idea about the spedo being off, but my car's OD has always lined up with what google maps says.
Say it was 5mph high at 65mph though (car says im going 70 and im actually going 65), then that's only a mpg bias of 8% or so. So even my bad tanks of 19 mpg are more than 17 mpg.
What do you mean by 50mpg cruise control? Do you mean 50mph? If so, 50mph is not a very efficient speed in a rotary engine car. Sure there is less wind resistance, but the engine is working at a very inefficient rpm. At an engine speed of say 2500rpm the engine is making much more power per unit fuel AND it is being put to use moving the car forward.
01-14-13, 02:30 AM
#37
Actually, now that I think of it... My speedo is off. At 110kmph I'm actually doing 100kmph verified by GPS and having a friend drive 100 in his vehicle and I was behind doing 110kmph. So if I am getting 350 kms per 62-63 litres or about 13mpg, does that mean I'm actually getting worse mileage because my speedo is faster? I'm also running 205/55/16 (stock turbo size) on my S5 N/A.
I'm assuming you're generalizing S4's because if I was able to drive 190 miles and filled up 6 gallons that clearly shows I got an average of 30+ mpg.
EDIT: When you say 50mpg cruise control, do you mean 50MPH? Aha.
I'm assuming you're generalizing S4's because if I was able to drive 190 miles and filled up 6 gallons that clearly shows I got an average of 30+ mpg.
EDIT: When you say 50mpg cruise control, do you mean 50MPH? Aha.
110kmph is 10% faster than 100 and so you would be getting 10% better gas mileage as reported by your car's OD. Divide your 13 by 1.1 and you'll get the true mpg
01-14-13, 03:51 AM
#38
But wouldn't mean my trip is showing more kms then I'd actually driven. Meaning I see 350kms a tank, but actually getting 10% less kms? Therefore worse gas mileage. If this is the case, my car with 106000kms actually has less mileage? Aha
Last edited by ryan2949; 01-14-13 at 03:56 AM.
01-14-13, 10:25 AM
#39
01-14-13, 02:46 PM
#41
If your engine is ported, you may benefit from revving even higher. The stock engine peak torque occurs at 3800rpm (probably because of the 6 ports opening up) but if the engine is ported, then it could be up around 4500 or even 5000 (I'm not really sure because I haven't seen many dyno charts of ported versus non ported engines)
01-16-13, 10:22 PM
#43
I get 215 miles to the tankfull on my stock ecu/turbo 550/680 inj, RB fuel cut defensor, 4" trust turbo back exhaust! And on my other turbo hi comp hybrid turbo, standalone ecu 750/ 1000inj 3" inch turbo back exhaust, I get 320-340 to the tank full!
06-04-13, 01:17 PM
#47
Senior Member
I have a terribly running beat up 88 vert running on 10 year old square tires. Terrible alignment and a 1.75" single exit exhaust to one stock bonez muffler.
I get 15-17 around town. Managed 21 mpg on two tanks all highway with some speeding, top down both trips.
I get 15-17 around town. Managed 21 mpg on two tanks all highway with some speeding, top down both trips.
06-04-13, 02:46 PM
#48
Senior Member
I'm pretty sure the mpgs stem from the fact that the electronics in these cars is ancient..i mean look at the rx8...it gets like 18mpg while putting out 2xx hp..there should be a government rebate where we can get stand alone ECUs for cheap..
06-04-13, 04:21 PM
#49
"Smells like coolant.."
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I get 14.5 mpg on average...I've had terribad blown coolant seals on at least one rotor for two years now and I've got a lead foot the size of the empire state building, I race everywhere I go and DD it. RB true dual, 245/45/16's in the rear, etc. Make of it what you will.
06-04-13, 08:17 PM
#50
MECP Certified Installer
S5 NA vert, only 12k on the motor and it has high compression (110+).
I always fill up with exactly 10 gallons of gas. I do only city driving and my mileage is about 10.8 mpg to 12.5 mpg.
Street port, catback with presilencer, no cat, with 2 magnaflow mufflers at the back.
I always fill up with exactly 10 gallons of gas. I do only city driving and my mileage is about 10.8 mpg to 12.5 mpg.
Street port, catback with presilencer, no cat, with 2 magnaflow mufflers at the back.