Gas Mileage
2nd Gear Member
Joined: Dec 2007
Posts: 300
From: Arizona
RE: Gas Mileage
Get a Multispark Capacitative Discharge Ignition box, not a Pertronix points eliminator, UNLESS you have the money for both. Points eliminators are a great convience but will not help burn fuel more efficiently. Properly set up points will perform just as well as Pertronix. I have used both for years. I have Pertronix, they are great, but they ONLY eliminate points.
Hell yes. At about 90 MPH in a 65 coupe. Follow the recomendations - don't over inflate your tires. Starfury, 69fecoupe and the others.
Sorry to keep quoting everybody but good advice is hard to argue with.
I have no idea where the average joe is going to get nitrogen for their tires. Is it really cost effective?
Put a black color code spring in the carb secondary, opens later.
Set the accelerator pump for the minimum squirt.
Drop the main jets 2 or 4 sizes.
If your desperate put a power valve blocker in the carb or get a power valve with a higher vac rating.
Tighten the alternator belt, probably what is squealing.
There is alot more, I'm going to get a beer.
Haveyou ever seen a tire tread separate on the freeway?
the single most important way to increase your gas mileage is to keep your foot out of it.
Coast up to lights, take off like an old woman, don't touch the brakes unless really needed
Coast up to lights, take off like an old woman, don't touch the brakes unless really needed
I have no idea where the average joe is going to get nitrogen for their tires. Is it really cost effective?
Put a black color code spring in the carb secondary, opens later.
Set the accelerator pump for the minimum squirt.
Drop the main jets 2 or 4 sizes.
If your desperate put a power valve blocker in the carb or get a power valve with a higher vac rating.
Tighten the alternator belt, probably what is squealing.
There is alot more, I'm going to get a beer.
6th Gear Member
Joined: Aug 2007
Posts: 5,896
From: Elk Grove, CA
RE: Gas Mileage
Points work great...aside from the fact that they're constantly degrading after the first time you use them. It's this degradation that can slowly decrease fuel efficiency. This is where the Pertronix has merit over points; keeping the engine in good tune. Plus,several units (like the Pertronix Ignitor II) have variable dwell. It won't work quite as well as an MSD unit, but it'll still be better than points.
2nd Gear Member
Joined: Dec 2007
Posts: 300
From: Arizona
RE: Gas Mileage
The points degrade because they are switching a high current into the coil primary. It is the high current load that eats the contacts.
With CDI the points are switching a very low current to the electronics of the CDI box, therefor the points last alot longer. There is virtually no wear and tear on the contacts because the box provides the high current to the coil primary, not the points.
With CDI the "dwell" becomes irrelevant.
I have both on my car. It is just about budget.
With CDI the points are switching a very low current to the electronics of the CDI box, therefor the points last alot longer. There is virtually no wear and tear on the contacts because the box provides the high current to the coil primary, not the points.
With CDI the "dwell" becomes irrelevant.
I have both on my car. It is just about budget.
2nd Gear Member
Joined: Oct 2007
Posts: 164
RE: Gas Mileage
Gearing hasen't been mentioned, but that also involves your budget.
As for tire pressure, I owned one of those Explorers with the Firestone tires. I ran them at 35-37 PSI. They had around 88,000 mi on them when I got my free replacements through the recall. After buying it, I immediatly noticed the sloppiness of the tires at the Ford reccomended 26-28 PSI on the door tag and thought the heck with that! I ran them slightly over the Firestone reccomendation and got better milage, better handeling and very even tire wear(Albiet a slightly stiffer ride, but no different than your ave. truck or van) and as for traction, I never really needed the 4WD on or off road unless in mud. IMO Firestone got burned on that deal by Ford's low pressure rec. trying to get a softer ride for the "Soccer Mom" type that wanted thier SUV to ride like a caddie or towncar. BTW-I ran them at that PSI on the recomendation of a mech. friend who worked for a tire store for20+ years andis an ASE Master Mech. and lead fleet mech. for his current employer (30,000+ cars, trucks, vans &busses). I also put most of those 88,000 miles on the tires going back and forth between my restaurants on the freewaywith 65 and 70 mph speedlimits.
But by and large the best improvement in milage is behind the wheel, just stay off it as has been mentioned.
And 65Coupester -try not to get that beer confused with your sixpack of liqued nitrogen, i'd hate to hear that you "broke" your lips.
As for tire pressure, I owned one of those Explorers with the Firestone tires. I ran them at 35-37 PSI. They had around 88,000 mi on them when I got my free replacements through the recall. After buying it, I immediatly noticed the sloppiness of the tires at the Ford reccomended 26-28 PSI on the door tag and thought the heck with that! I ran them slightly over the Firestone reccomendation and got better milage, better handeling and very even tire wear(Albiet a slightly stiffer ride, but no different than your ave. truck or van) and as for traction, I never really needed the 4WD on or off road unless in mud. IMO Firestone got burned on that deal by Ford's low pressure rec. trying to get a softer ride for the "Soccer Mom" type that wanted thier SUV to ride like a caddie or towncar. BTW-I ran them at that PSI on the recomendation of a mech. friend who worked for a tire store for20+ years andis an ASE Master Mech. and lead fleet mech. for his current employer (30,000+ cars, trucks, vans &busses). I also put most of those 88,000 miles on the tires going back and forth between my restaurants on the freewaywith 65 and 70 mph speedlimits.
But by and large the best improvement in milage is behind the wheel, just stay off it as has been mentioned.
And 65Coupester -try not to get that beer confused with your sixpack of liqued nitrogen, i'd hate to hear that you "broke" your lips.
5th Gear Member
Joined: Sep 2006
Posts: 2,266
From: Australia
RE: Gas Mileage
I run my tyresnear or even up to the max inflation, but not over.
as for the nitrogen thing, i call BS!!!!
Air is 80% nitrogen. You have to have 100% nitrogen for it to do all the things claimed. And thats nearly impossible to get and no way your average tyre shop is gunna be able to get all the air out of your tyres before refilling with nitrogen.
Here's some info
http://www.racq.com.au/cps/rde/xchg/...s_ENA_HTML.htm
as for the nitrogen thing, i call BS!!!!
Air is 80% nitrogen. You have to have 100% nitrogen for it to do all the things claimed. And thats nearly impossible to get and no way your average tyre shop is gunna be able to get all the air out of your tyres before refilling with nitrogen.
Here's some info
http://www.racq.com.au/cps/rde/xchg/...s_ENA_HTML.htm
6th Gear Member
Joined: Aug 2007
Posts: 5,896
From: Elk Grove, CA
RE: Gas Mileage
ORIGINAL: 65Coupester
The points degrade because they are switching a high current into the coil primary. It is the high current load that eats the contacts.
With CDI the points are switching a very low current to the electronics of the CDI box, therefor the points last alot longer. There is virtually no wear and tear on the contacts because the box provides the high current to the coil primary, not the points.
With CDI the "dwell" becomes irrelevant.
I have both on my car. It is just about budget.
The points degrade because they are switching a high current into the coil primary. It is the high current load that eats the contacts.
With CDI the points are switching a very low current to the electronics of the CDI box, therefor the points last alot longer. There is virtually no wear and tear on the contacts because the box provides the high current to the coil primary, not the points.
With CDI the "dwell" becomes irrelevant.
I have both on my car. It is just about budget.
6th Gear Member
Joined: May 2005
Posts: 5,736
From: MD/WV
RE: Gas Mileage
It may better to get a second "beater" car that gets good gas mileage. I tracked my fuel economy in my daily driver last year carefully and was averaging about 55mpg. Not bad for a 700$ beater...
6th Gear Member
Joined: Feb 2007
Posts: 7,635
From: state of confusion
RE: Gas Mileage
ORIGINAL: 67 evil eleanor
However looking over some info, the Nitrogen did prolong the tread life of the tire by a wopping 86%in one study with big trucks.They suggest that the Nitrogen is more stable, less corrosive, no mostureandmantains pressure betterbetter that the 80/20 we breath.
However looking over some info, the Nitrogen did prolong the tread life of the tire by a wopping 86%in one study with big trucks.They suggest that the Nitrogen is more stable, less corrosive, no mostureandmantains pressure betterbetter that the 80/20 we breath.
That does not translate over to passenger car tires that MIGHT last 40,000 and vehicles that rarely go past 150,000.
Norm
6th Gear Member
Joined: Feb 2007
Posts: 7,635
From: state of confusion
RE: Gas Mileage
ORIGINAL: toolwench
I could go into the whole tire speech, but I won't. I'll try to keep it quick.
As I said, I got this knowledge from Bobby Ore who among other things, did the official tire test to find out why Explorers were overturning when a rear tire blew. He knows tires.
Look at the side of your tire as it sits. It's not perfectly round. There's a bulge in the sidewall on the bottom. Imagine that tire spinning, keeping that same bulge on the bottom. That means the sidewall is flexing. Flexing straight then bent, straight then bent, continuously as you drive your car. This is one of the biggest ways heat builds up, the flexing and straightening of the sidewall--the weakest part of a tire--as it handles the weight of the car. The more pressure you have in that tire, the less bulge, the less heat build up.
It is a misconception that having more pressure in your tires makes them wear down the middle. This used to be true on old tires, but nowadays, the technology behind the weaving of the steel belts is such that they will collapse inward (to help handle rocks, curbs and potholes), but they do not push outward...certainly not enough to create uneven tire wear. Don't believe me? Find a tire and push on it. I didn't believe it at first, either but it's true.
Yes, having more air in the tires changes the way the car handles...it makes it tighter, less sloppy because the sidewalls aren't flexing as much. With more air pressure, the tread is pressed to the ground more thoroughly, making better contact. I mean, depending on the width of your wheels, there's really a comparatively small area of rubber making contact with the road...which means every square inch is very, very important.
The reason you see freeway blowouts is because of people who don't fill their tires up and enjoy a mushy ride. That sidewall flexes like crazy, building up an enormous amount of heat until it can't take it anymore.
You should try filling yours up and see. (If you don't like how the car rides, let the air back out, but then you'll never know if your mileage increased.) You'll also find the tires last longer. Bobby got 80,000 miles out of a set of tires on his full-size SUV. I could go into another speech on that, too, but I'll save it because I'm not the only one who posted that tire pressure makes a difference in gas mileage.
I could go into the whole tire speech, but I won't. I'll try to keep it quick.
As I said, I got this knowledge from Bobby Ore who among other things, did the official tire test to find out why Explorers were overturning when a rear tire blew. He knows tires.
Look at the side of your tire as it sits. It's not perfectly round. There's a bulge in the sidewall on the bottom. Imagine that tire spinning, keeping that same bulge on the bottom. That means the sidewall is flexing. Flexing straight then bent, straight then bent, continuously as you drive your car. This is one of the biggest ways heat builds up, the flexing and straightening of the sidewall--the weakest part of a tire--as it handles the weight of the car. The more pressure you have in that tire, the less bulge, the less heat build up.
It is a misconception that having more pressure in your tires makes them wear down the middle. This used to be true on old tires, but nowadays, the technology behind the weaving of the steel belts is such that they will collapse inward (to help handle rocks, curbs and potholes), but they do not push outward...certainly not enough to create uneven tire wear. Don't believe me? Find a tire and push on it. I didn't believe it at first, either but it's true.
Yes, having more air in the tires changes the way the car handles...it makes it tighter, less sloppy because the sidewalls aren't flexing as much. With more air pressure, the tread is pressed to the ground more thoroughly, making better contact. I mean, depending on the width of your wheels, there's really a comparatively small area of rubber making contact with the road...which means every square inch is very, very important.
The reason you see freeway blowouts is because of people who don't fill their tires up and enjoy a mushy ride. That sidewall flexes like crazy, building up an enormous amount of heat until it can't take it anymore.
You should try filling yours up and see. (If you don't like how the car rides, let the air back out, but then you'll never know if your mileage increased.) You'll also find the tires last longer. Bobby got 80,000 miles out of a set of tires on his full-size SUV. I could go into another speech on that, too, but I'll save it because I'm not the only one who posted that tire pressure makes a difference in gas mileage.
I am fully aware of tire flexing, and also that you cannot possibly eliminate all of it. There does become a point where diminishing returns and increased risk fromother sources takes over. IOW, let's say that the first 3 psi buys you a 1% fuel economy benefit. The next percent will take more than 3 more psi. And so on. It's a progressive thing, meaning that each additional % of fuel economy benefit becomes increasingly more difficult to obtain (and ultimately becomes impossible to do).
Excessive pressure leaves the tire carcass more vulnerable to impact damage from potholes, railroad crossings, driveway entrance mismatches, etc. The tire can no longer soften the blow seen by everything all the way from the tread to the driver's seat. This effect is very much like the "crush distance" required in new cars, where you allow something to "give" a little in order to reduce the forces generated as a result.
As far as handling goes, pressures that are increased without regard to possible changes in vehicle behavior (I'm talking about understeer/oversteer balance here) can lead to unexpected results. Remember that your front wheel camber changes during suspension movement, while rear camber does not (I think we can ignore the tiny amount of axle flex that occurs), and that tire grip is partly a function of both tread rigidities and wheel camber.
Today's tires are less susceptible to center tread wear than their 60's predecessors, but they are most definitely not totally immune. Under internal pressure,the tread center can still only expand outward. I can notmaintain the pressures that I have used for autocross with certain combinations of car and tire as daily-drive pressures on those same tires (as high as 48f/43r for a minute at a time). Not from the ride penalty (I'm more tolerant of this than most). Center tread wear. The 37f/33r (measured hot, BTW) that I ran last year is the only setup that I can leave alone. Soft, semi-competition tires, FWIW.
Certain combinations of pressures on one car's tires permitted drifting-level amounts of oversteer - this on a FWD car, no less. I won't say what the particular ranges of pressures were,because it'll differ from one vehicle to another.But both front and rear were well above the door sticker recommended pressures. That sort of handling behavior is exactly what you do not want when your driving situation is going to hell in a handbasket. Without adequate run-off room and without having any reason to expect it, I'll all but guarantee that most people would lose control and loop it.
In order to even attempt inflation pressure suggestions, at least the car's weight and its tire size(s) should be known.
Norm
3rd Gear Member
Joined: Dec 2007
Posts: 923
From: Colorado
RE: Gas Mileage
Tire pressure is important, and be sure your air filter is clean and a good one that breathes well. You can also upgrade the exhuast, which will give you more power and should increase mileage because the engine can breathe better. It is also very important to have the engine in good tune, and the elect. ignition will help that. Also, much of gas mileage is driving habit. Like said before, dont carry any weight you dont need, and drive slowly and smoothly. accelerate as slowly as you can, and dont go really fast (you get way worsemileage at 75 then you will at 55).
And if your friends are nice enough either ride with them, or ask them for gas $ when you drive them. You are lucky if they give it to you though. I will drive my friends all over the place (I have a nice car, and am the safest driver in the group) and they wont even give me gas money if I drive them like 100 miles. its very frustrating... but its not worth riding with some of my crazy friends.
And if your friends are nice enough either ride with them, or ask them for gas $ when you drive them. You are lucky if they give it to you though. I will drive my friends all over the place (I have a nice car, and am the safest driver in the group) and they wont even give me gas money if I drive them like 100 miles. its very frustrating... but its not worth riding with some of my crazy friends.