mpg

[Timon]

I believe what he means is what I had planned on doing. Use the same pump and let it decide when it is full (not rounding up to the next dollar or continuing to fill at all). When doing this it allows the test to be more precise since the same pump is used in the same method.

You will know your exact MPG the next time you fill up; using the same method and dividing the miles driven by the amount of fuel put into the car, this is the best way to find out the MPG.

Tomorrow night, I'm going to test all 3 series on some back roads, with various stop signs and turns. This will be standardized as much as possible, using the same route, the same gas station, and the same pump. I'm hoping to go about 40 miles, (I may cut that down) on each trip, and then filling again. Since it will be during the evening hours on a weekday I shouldn't run into much traffic, preventing any unplanned 'stops & gos', therefore giving all 3 methods the same amount of stops.

[dr3amr2]

^^ Lol do you sleep Timon? It's like 2AM

I probably misread that section from Aaron, because what you said made a lot more sense to me. This is how I always pump my gas but when I read "do not top it off" it just confused me.

Have fun, stay safe and good luck on your test! I'm interested to see what kind of numbers you can come up with even if it prove that my driving method is obsolete. Just remember to keep the way you brake and coasting consistent with all of the test trials. O yeah, try not to tail gate people or enter their slipstream because that will also add another variable that will affect your MPG.

[te51levin]

I think you are confusing mechanical advantage (leverage) with mechanical efficiency (low loss to friction, heat, etc). The fact that your tranny is in a lower gear does not make the transfer of power from engine to roadway more efficient.

Originally Posted by dr3amr2

This part brings us back to where AustinTxMR2 and I started. When is it appropriate to shift? (To make things simple this is for a flat straight road with no hills) My questions for this section are how does one go about in finding the logical choice of when to shift up?

You shift as soon as the engine will pull the next gear smoothly. I can upshift right around 2000 RPM in most gears, and the engine doesn't mind as long as it is above 1600 RPM or so - less if it is not under load. If the engine bucks or complains or detonates, it wants more RPM.

To answer your question about refuelling - by not topping off, you allow the pump to stop at the same point, automatically. It should fill to the same point every time. That's why I suggested filling up, but not topping off, before you begin. The fill point before and after will be a constant, not a variable. You will start and finish each tankful at the point where the pump shuts off. You have to read the miles driven since the previous fill-up and compare that to the number of gallons it took the pump to return to the auto-shutoff point when refilling.

[Timon]

Originally Posted by dr3amr2

^^ Lol do you sleep Timon? It's like 2AM

I probably misread that section from Aaron, because what you said made a lot more sense to me. This is how I always pump my gas but when I read "do not top it off" it just confused me.

Have fun, stay safe and good luck on your test! I'm interested to see what kind of numbers you can come up with even if it prove that my driving method is obsolete. Just remember to keep the way you brake and coasting consistent with all of the test trials. O yeah, try not to tail gate people or enter their slipstream because that will also add another variable that will affect your MPG.

Don't worry, I will make the test as even as possible; however, (this is the bad part) the test has been delayed ~1 week, for the good of my vehicle.



I think the picture explains it all . It's a lot of work , but once it's all painted though I will complete the test in style .

Back on topic of MPG, most of my driving is utilizing some of all of the above methods. I usually do WOT to about 3.5k, shift into second and follow the 3k shifting point from there on up to speed, and then once up to speed I get into the highest comfortable speed.

[Teado]

I've been getting consistently 35mpg on the freeway, and about 28 around town.

Stock, 86 mk1, 4age, usually about 3200rpm shifts.

[OldSkool]

Originally Posted by AustinTxMR2

BTW, my car runs out of gas going uphill when it takes 10.1 gallons to fill the tank.

MK1's have a ~10.6 gallon tank including the air gap, I have read.
I get just under 9 gallons in there to fill it with the fuel light just starting to glow.

[Teado]

Not topping off the tank also prevents the gas from spilling out...

Just the yesterday the gas attendant asked if I wanted it topped, I said "no" and he continued to top it off, spilling gas down the side of my car...

<Sure wish Oregon wasn't mandatory full service>


Note: Got my highest mpg yet, on rural roads doing ~ 63mph, got 37 mpg.

[te51levin]

Originally Posted by Teado

<Sure wish Oregon wasn't mandatory full service>

You and me both. They trust us with automatic weapons, but not with a gas pump. We are paying otherwise unemployable people to do a job we don't want them to do. The state calls it employment, but in my book, it's welfare

[esreveRBackwards]

Originally Posted by LordNikon

Replaceing these with full under body panels and a rear air diffuser is also supposed to increase fuel economy.

Has anyone tried those new Pulstar plugs?
The Pulstar™ Pulse Plug is not just another spark plug!

You know any links to the full body panels?

Was thinking about the pulstar plugs. More efficent spark... unno..

[te51levin]

Originally Posted by esreveRBackwards

Was thinking about the pulstar plugs. More efficent spark... unno..

If it was really a better product - if it really produced more effective combustion, which benefits power, emissions, and economy all at once - OEMs would be jumping over each other to use them. They are not.

[esreveRBackwards]

Originally Posted by te51levin

If it was really a better product - if it really produced more effective combustion, which benefits power, emissions, and economy all at once - OEMs would be jumping over each other to use them. They are not.

I do agree with you but also consider the cost of these plugs. It may not be cost effective for OEM to put them in. Also, if this product does what it claims and was put into cars in mass. It would effect the gas/oil companies that make "donations" to said OEMs..

I'm willing to spend the $ to find out... I'll update once I get them in and test them.

[te51levin]

Originally Posted by esreveRBackwards

Also, if this product does what it claims and was put into cars in mass. It would effect the gas/oil companies that make "donations" to said OEMs..

I don't buy that consipracy theory stuff - at least not in this case. Believe me, if Toyota or Ford or Mazda could get better mileage by chucking in some fancy spark plugs, they'd do it in a heartbeat, because it would sell more cars. That's ultimately what makes them money and makes them successful corporations.

You've heard the expression: If it sounds too good to be true, it probably is!

[Teado]

Originally Posted by te51levin

You've heard the expression: If it sounds too good to be true, it probably is!

Last time I heard that is when I bought my 2... hasn't let me down yet.

But as for the spark plugs.. I'm not convinced yet. Besides, how many tanks of gas would you have to burn through to recoup the cost from just the mpg increase?

[LokiRx7]

Originally Posted by te51levin

I don't buy that consipracy theory stuff - at least not in this case. Believe me, if Toyota or Ford or Mazda could get better mileage by chucking in some fancy spark plugs, they'd do it in a heartbeat, because it would sell more cars. That's ultimately what makes them money and makes them successful corporations.

You've heard the expression: If it sounds too good to be true, it probably is!

It would have to net huge savings to offset the cost of the plugs. All car manufacturers are out to save a buck, if they found a mystical spark plug that netted at least 10 mpg they would consider it, I doubt everyone would jump on it. Anything less than 10mpg wont be worth $25 per plug, not just because of the added intial cost of the vehicle either. That cost would be passed on to the consumer when they did a tune up. People would start noticing that the spark plugs were enormously more expensive and tell their friends not to get a (Insert manufacturer here) because their spark plugs are $25 a piece, and thats outrageous because every other car they have had tuneups have been near $100 or more less becuase of cheaper plugs.

I do believe that its far too good to be true, I have seen numerous tests as to whether or not a significantly stronger spark actually benefitted compustion. It made combustion more uniform, a little less prone to pre-detonation. It did not however add any significant power gains. I dont think street cars on pump gas will ever see a situation where it would receive a significant benefit. I upgraded my ignition on my Rx-7 from an ancient canister coil, and built a direct fire ignition with capacitive discharge plugs. I managed to see a 5 mpg increase, which could easily be attributed to me changing the dirty air filter and fuel filter, along with replacing canister coils and ignitors that were from 1981 and were probably a little tired to say the least. Not enough alone to justify the change really, however I have MUCH easier cold starts, which were difficult because of the big aftermarket carb and lack of a choke. That alone made it worth it to me.

But we are talking about computer controlled fuel injected cars. They are certainly not hard to start, and I doubt you will see any gains that couldnt be seen with fresh oem plugs a new oem coil and a new oem ignitor.

And you would see every hyper-miling list on the internet updated with Pulsestar plugs! I dont see anyone reccomending them! Well other than pulsestar themselves...

[te51levin]

Originally Posted by LokiRx7

Anything less than 10mpg wont be worth $25 per plug, not just because of the added intial cost of the vehicle either. That cost would be passed on to the consumer when they did a tune up. People would start noticing that the spark plugs were enormously more expensive and tell their friends not to get a (Insert manufacturer here) because their spark plugs are $25 a piece, and thats outrageous because every other car they have had tuneups have been near $100 or more less becuase of cheaper plugs.

I have to disagree with you here. Ten miles per gallon is a HUGE difference; if two manufacturers produce comparable cars and one gets 10 MPG more, it would be a huge advantage which they could sell as (for example) reduced fuel costs.

Assume one year at 12,000 miles at 30 MPG = 400 gallons burned, times maybe $3 a gallon = a fuel cost of $1200. Change that to 40 MPG; you now burn 300 and your annual fuel cost is $900, a savings of $300 over the first year alone. Any manufacturer would happily spend $25 extra per plug to achieve that, as would any reasonable owner...especially considering that a) most cars don't need "tune ups" anymore (there is nothing to tune) and their plugs typially last 60K to 100K miles, and b) many modern cars take iridium plugs which are already $12-16 each anyway, so $25 each does not represent a huge jump in maintenance costs.

Not that they work - just that if they did, OEMs would be on them like white on rice.

[LokiRx7]

Originally Posted by te51levin

I have to disagree with you here. Ten miles per gallon is a HUGE difference; if two manufacturers produce comparable cars and one gets 10 MPG more, it would be a huge advantage which they could sell as (for example) reduced fuel costs.

Assume one year at 12,000 miles at 30 MPG = 400 gallons burned, times maybe $3 a gallon = a fuel cost of $1200. Change that to 40 MPG; you now burn 300 and your annual fuel cost is $900, a savings of $300 over the first year alone. Any manufacturer would happily spend $25 extra per plug to achieve that, as would any reasonable owner...especially considering that a) most cars don't need "tune ups" anymore (there is nothing to tune) and their plugs typially last 60K to 100K miles, and b) many modern cars take iridium plugs which are already $12-16 each anyway, so $25 each does not represent a huge jump in maintenance costs.

Not that they work - just that if they did, OEMs would be on them like white on rice.

I was saying anything less than 10 mpg.. But you would also have to understand that most consumers dont keep track of what they are spending for fuel. And regaurdless of when they have a tune-up they will notice that cost far more than any savings they get in fuel.

You see I use to work at a dealership in the service department, and I have several friends and family the lease cars. Ford switched to Ceramic pads on several models and whenever anyone came in to have their car serviced, if it needed brakes they could have cared less that it produces less dust, ceramics are far more expensive then semi-metallics. While I was working at Ford my grandmother hated having her car serviced, because of the cost, she was willing to change brands if she could find one that had cheaper service costs. A buddy of mine bought an MR2, and he didnt work on his own cars. So when he brought it in for a full tune up after he bought it his eyes were wide as 50 cent pieces when he found out how much platinum plugs were.

I cant stand some of the people I know when it comes to cars, granted if they're was a large fuel savings to be had. I would certainly spend the extra money, as I am sure you would too.

They're needs to be a very large gain before a manufacturer will even think about it. And even then, they wont jump on them per say. They will wait until they do their own testing or someone else sticks them in their cars. $25 per plug is a big risk to gamble on. What I meant was if its 1,2,3,4,5 mpg they might look the other way. If it netted 8,9,10 or more, then yes it would be something they would look into. But after some thought I am sure they would find other ways of bringing the initial costs down.

$25 per plug may not sound aweful when your thinking of a huge corporation. But you have to figure if they are buying them for say, a Taurus, they will need hundreds of thousands of those plugs. Which will drive up the cost of the vehicle quite a bit. I would figure the Japanese would put them in a few of their models, the ones that people are used to paying a premium for anyway, that would happen long before the real gas mileage champs saw them. I mean if the Yaris used the plugs and the fit didnt the Yaris could end up more expensive then the fit and for what? 5 mpg extra? Most people will settle on the cheaper car before the one that saves them more money in the long run.

[Achaikos]

your complaining about an mr2 fuel economy are you crazy???
i had a twin turbo 300 zx before my mr2 i would drive to one of the city and back in half a tank it was retarded. i also drove g35 (friends) and a mazda 626 both 6cyl they chew threw gas like crazy.
my mr2 gets like 4 times that with fast start and stops but i do short shift and i try to hit the apex of every turn.

[LokiRx7]

Originally Posted by Achaikos

your complaining about an mr2 fuel economy are you crazy???
i had a twin turbo 300 zx before my mr2 i would drive to one of the city and back in half a tank it was retarded. i also drove g35 (friends) and a mazda 626 both 6cyl they chew threw gas like crazy.
my mr2 gets like 4 times that with fast start and stops but i do short shift and i try to hit the apex of every turn.

Well before you tell me about cars with bad gas mileage, go buy a Ford F-250 crew cab, long bed with a 460 c.i. V-8 and a 3 spd auto with no overdrive. Yeah, I rarely saw 5 mpg unless I was coasting downhill with a tail wind.

And my toy is a ported Rx-7 with a big aftermarket carb. It and 8 mpg are good friends.

If there is a way to improve the MR2's economy, why not? Gas prices are just going to