Now up to 57.3 mpg at 60 mph in my 97 Saturn SC1
 

Gettin up there! Maybe I'll make it to 60 mpg when I finish aero mods and get my preheated fuel gizmo I built working. I wish I had lighter rims and tires, and a 98+ trans, but just too much money to change those things. Once the mods are stable, I'll make one try with gas additives just to see if they help or not.

This is a 97 SC1 5 spd 1.9L with AC and PS on normal 87 octane Mobil gas, no additives, driving at about 60 mph on the same 22 mi test loop I've been using with small hills and turnaround cloverleaf, etc, avg speed 57 mph, max speed 62 mph, outside temp about 60f, no wind, slight drizzle, no drafting trucks, no coasting, had to hit brakes 1 extra time due to traffic. All readings from my Scangage with error max about 1%. I also have a constant Air/Fuel LED readout and its not running lean. I had about 35 lbs of groceries in the car, but have the spare removed to reduce weight

Aero mods
- no antenna (I have a CD changer, who cares)
- no wipers (using RainX like my race car)
- Taped front end for lower drag with holes sized for optimal cooling (like my race car)

Engine/Trans
-hotter thermostat Napa 268
-105 ohm resistor on a switch instead of IAT sensor for 242-247f signal
-all synthetic fluids + Valvoline Synthetic Oil Treatment
-insulated hot air intake (actual temp about 150f) look in my pics at Saturnfans.com
-Champion copper plugs gapped .040
-Bosch plug wires

Other
-45 psi tire pressures

that's amazing - nice
 

that's amazing - nice work. you should really use the gaslog feature. i'm sure folks would like to see your tank-by-tank results too.

my firefly only gets that mileage around 53/54 mph.

What determined your gap on
 

What determined your gap on the spizzark plugs?

wow nice, i hvae a hard time
 

wow nice, i hvae a hard time keeping it above 50 mpg/55mph with tire pressure 55 psi + those areo mods sure rock!

And its a domestic! Nice job man.

Re: that's amazing - nice
 

My only problem is that I don't get to do much highway driving anymore. I did have the trip out east a couple weeks ago (50+ mpg thru Ohio at 65), and I'm still on that same tank of gas from filling it on cheap Indiana gas because I'm unemployed (or retired with no pension) anymore, and don't drive much except to the library, racquetball, grocery, or to visit friends, barely warming it up. Around town I'm only getting 38 or 39, but out on the highway I am getting it pretty tweaked. Last I looked this tank was at 43 mpg avg, and I should need gas by around the end of the month when I go on a trip to the races.

I been using my same test loop because its almost exactly the same driving each time because there are no stops and its steady speed except for the turnaround cloverleaf and getting back onto the expressway into traffic. It would be hopeless trying to test mods with my normal driving because you'd never know if the mod worked or not, because mpgs would end up being determined by destination and traffic conditions.

Re: What determined your gap on
 

One site I found (same guy that was advocating Acetone) said to reduce stock gap by 10 thousandths, so I reduced it by 5, figuring that 10 was 25%, and that was a huge change. 5 was only a 12% change. Diamondlarry has the same motor, and is also running a reduced gap.

Anyway, it seems to run fine. I didn't do a separate test with them at 40, then down to 35, so I really can't say there is any measurable difference in MPG due to spark plug gap. Larry did do a test with different brands of plugs, but I don't think he tried stock style copper Champions, just the fancy/expensive stuff.

Maybe someone else has done a heads up test on gaps and could tell me?

Re: What determined your gap on
 

Actually, I did use a set of standard NGK plugs in my test. If I'm not mistaken, I ran them at .030" Right now I'm running Halo Brisk plugs and the gaps can't be changed.
Congratulations on the mpg numbers! My numbers since the head swap have been 60-65 mpg at 55 mph and are at 63 mpg most of the time. I can't wait to see how things look when the cam timing gets set to where we want it. We were looking for a centerline of 102 degrees but it ended up at 96 because we ran out of time for getting it dialed in closer. Memorial day weekend will be when we get things dialed in correctly.

Re: What determined your gap on
 

I would guess my copper Champions are similar to the stock NGK's. My question was related to a test of lets say NGK's at stock .040 vs the same plugs regapped to .030 on the same cars, etc., with no other changes. I cheated and didn't do a test, so don't really know if the smaller gap helped.

If by chance you did try it with different gaps, could you tell us what was the results?

No, I didn't do a test of
 

No, I didn't do a test of different gaps. Since I did 5, 2 mile runs for each of 5 different plugs back to back, I was too tired to do anymore testing that day. The temp was in the mid to upper 80's and since I was doing testing, I had the windows rolled up and no A/C. Fran at hydrogen-boost.com suggested several times that I do a test of different gaps and I never got it done.
I think I mis-understood your statement about your mpg. I automatically [bold]***[/bold]umed you were talking about a steady cruise situation. :oops: The numbers I gave earlier were for steady cruising and not over a course like you did. A trip to Chicago sounds like fun. I won't be able to make the trip until after Memorial Day when I go to get the cam timing dialed in on my car. PM me with your location and we could start to make some plans.

57 mpg is impressive. If you
 

57 mpg is impressive. If you have that already, completing your aeromods would do a bit more than 60 mpg.

As for top speed, assuming you can't reach redline in the highest gear, the increase should be considerable.

Re: 57 mpg is impressive. If you
 

The only aero mods left that I can see as feasible for me are a belly pan and rear skirts. I also plan to replace my race tape front end with aluminum modeled after it what the tape has evolved to. I'm trying to get the aluminum to do all the aero mods for under $40, so its a challenge. Even if I keep it down to $40, it will be tough to get a payback in 50,000 mi. unless I can get 1 mpg avg on all driving with it, and that's assuming my free labor and a max of $50 for paint and supplies.

I'm not worried about top speed with this car. With my other mods the car is seriously detuned. Thats the price I'm paying to get high mpg out of a car with a 1.9L motor. I may see if I can come up with a system that switches it to a cold air intake when I press hard on the gas because its pretty sluggish if you're looking for passing power. I was only a 100 hp motor to start with and I've never had it over 4000 rpm. We'll see how it does pulling the sailboat and trailer to Canada in July, LOL.

The underbelly and rear
 

The underbelly and rear skirts are some of the most significant mods that can be made for the cheapest price. You'll definately see more than a 1 mpg improvement from them, at least a 2 mpg improvement from the rear skirts alone. The underbelly is even more significant.

However, you could also build side skirts, a rear spoiler designed for reduced drag(as opposed to downforce or looks), install shaved door handles, build wheel spoilers, use more aerodynamic mirrors, and seal up all seams(ie. use bondo, sand down and paint as needed. You could have nearly gapless doors and trunk).

It is possible to do those things for cheap, if you're good at scrounging and willing to either work with fiberglass or do some custom fabrication/welding. Even the shaved door handles can be done for cheap on your own, if you're willing to cut into your doors, root around the junkyards for the parts, design a remote-operated system to actually open and close your doors, weld metal plates back to the doors to seal them, and actually sand and paint them back to normal.

Further, you might be using a high tire pressure, but are you using genuine LRR tires? Skinnier tires will also reduce aero drag and if they are LRR tires, significantly reduce rolling drag.

each of those things might not be much by themselves, but added together as a whole, the impact on fuel consumption would be astounding. There are individuals that have heavily modified Honda CRXs to achieve 90 mpg with a cost in the few thousand dollar range for everything. I imagine similar results can be had with a heavily modified Saturn.

I might consider doing the
 

I might consider doing the wheel spoilers integrated with the belly pan, but other than that I probably won't be doing anymore mods to the body.

As for tires, its a shame that the tires that are on it have so much tread left on them. I looked at replacing them with some that are a larger diameter as well as lighter, and it turns out they also happen to be LRR tires. They are OEM on BMW's I think, and not too expensive, either. Continental ContiPro Contact in 195/65-15

I found an article posted by Matt Timion.....
New Fuel Efficient Tires Could Save Long Islanders $150 And Reduce U.S. Oil Dependancy By 275,000 Barrels a Day


Location: SLC, UT
Posts: 1625
View My Garage
Original Article: https://schumer.senate.gov/SchumerWebsite/pressroom/press_releases/PR01924.pf.html

SCHUMER: NEW FUEL EFFICIENT TIRES COULD SAVE LONG ISLANDERS $150 AND REDUCE U.S. OIL DEPENDANCY BY 275,000 BARRELS A DAY

Schumer touts new tire technology that cuts reliance
on foreign oil and saves money at the pump

New Schumer study finds less than 12 percent of LI tire stores sell fuel efficient tires – and Schumer reveals where to find them

US Senator Charles E. Schumer today announced a plan to require the federal Government to establish efficiency standards for the replacement tires drivers buy when the originals on their cars wear out. Most current replacement tires are between 20 and 60 percent less efficient than the original tires automakers equip cars with to help meet federal fuel economy standards.

Schumer released data showing that for an extra $5 to $12 per set of replacement tires, the average motorist can reduce his or her gasoline consumption by 1.5 to 4.5 percent, saving $50-$150 over the life of the tires. This data was confirmed by California Energy Commission, which is that state's state's primary energy policy and planning agency.

"If most Long Islanders knew they could invest an extra $12 in a set of tires and then save up to $150 at the gas pump, they'd jump at the opportunity. It's a huge savings for less than the cost of a tank of regular unleaded," Schumer said. "Unfortunately, there aren't enough of these tires, and the ones that are on the market are tough to find. But if fuel efficient tires are good enough when you buy a new car, they should be good enough when its time to replace those tires down the road – and tire manufacturers should make that option available for every car, truck, SUV, and minivan driver."

According to the National Resources Defense Council, the United States could save 275,000 barrels of oil a day by the year 2010 if all replacement tires were as efficient as the originals. In New York alone, efficient replacement tires would save 150 million gallons of gasoline and $240 million a year. Savings nationwide would total between $2.5 and $7.5 billion a year, according to Green Seal Environmental Partners, an independent, non-profit organization that produces Consumer ReportsTM -like investigations into the environmental friendliness of consumer products.

Tire efficiency is measured through rolling resistance, or the amount of energy needed to roll a tire down the road. Because of their higher rolling resistance, replacement tires are as much as 60 percent less efficient than the original tires that automakers use to help meet the federal Corporate Average Fuel Economy (CAFE) standards, according to Green Seal. If all replacement tires were as efficient as the originals, fuel economy nationwide would improve by about 3%, and the United States could save 5 billion barrels of oil between 2007 and 2050, according to the National Resources Defense Council.

Schumer's proposal today directs the National Highway Traffic and Safety Administration, a division of the US Department of Transportation, to establish an efficiency standard and labeling requirements for replacement tires so consumers know if the tires they buy are as efficient as the ones that came as original equipment when their cars were new. These standards would be reviewed and updated every three years to keep up with improvements in tire technology.

Schumer would also create a new consumer information program to promote the purchase of energy-efficient replacement tires including purchase incentives, Internet website listings, and printed fuel economy guide booklets. Schumer said that this information is essential because few drivers know about these tires and even fewer tire retailers in New York and across the nation sell such tires.

Schumer released a new study today of over 100 tire retailers in Nassau and Suffolk counties that found just 12 percent of them currently carry high-efficiency tires. Of 106 Long Island tire retailers contacted on August 4 and 5, only 13 reported carrying any of 16 tire models that are highlighted by Green Seal as fuel efficient. For a list of stores that sell the high efficiency tires click here.

The specific tire models studied by Schumer are the Bridgestone B381, Nokian NRT2, Sumitomo HTR 200, Dunlop Graspic DS-1, Dunlop SP40 A/S, Goodyear VIVA 2, Continental ContiTouring Contact CH95, Michelin Pilot Alpine, Michelin Energy MXV4 Plus, Dunlop SP WinterSport M2, Michelin Arctic AlpineXL, Dunlop Axiom Plus WS, BF Goodrich Long Trail T/A, Michelin XPS Rib, Michelin LTX M/S and Bridgestone Dueler A/T D693 tires. Schumer researchers asked for a variety of tire sizes, from 185/70R14 models appropriate for an economy car like a 2001 Honda Civic to 245/75R16 models that would fit a full-size SUV like 1997 Chevrolet Tahoe.

California Energy Commission research has shown that fuel-efficient tires perform at the same safety level as the replacement tires that are currently used by cars throughout the United States. Tire manufacturers can use materials like silica to stiffen tires and lower their weight. Improved tread design can also improve rolling resistance.

"By guaranteeing that replacement tires are as efficient as a car's original tires, drivers can make a small, smart, and effective investment that delivers large returns – all while decreasing our dependence on oil the oil we import every day," Schumer said.

Re: that's amazing - nice
 

Something else I didn't understand...

Why is it that your Metro with its tiny 1.0L motor gets 59 mpg average according to your gas log thing, yet can only get 57 mpg if you drive at 53-54 mph?

What doesn't make sense is that you are getting better mpg in normal driving that what you would get under very advantageous conditions (ie at 53-54 mph drag is very low and you'd be in top gear all the time).

If I was to drive a steady 53-54 mph I'm pretty sure I'd be getting at least 60 and maybe up to 63 mpg. I haven't tried any long loop type test at that speed yet, but that would be my guess for expected results.

Quote:Something else I
 

You're new to the site, which means you haven't become introduced too well to the idea that hypermiling is best done in the mountains or around town. You can't run engine off on the highway, :p

Hmmmm, I don't shut the
 

Hmmmm, I don't shut the engine off. If i'm coming up to a light I put it in neutral and roll up to it, trying to time when i get there to when the traffic will be moving again, but that's about it.

I swapped some 1.5 qts of the oil for 5w-20 Mobil 1 and ran the test loop again, but at 55 mph instead of my normal 60 mph. Avg speed was 53 instead of 57. Anyway, the result was 59.2 mpg on the scangage. I was expecting 60, but I may be getting to the law of decreasing returns.

Engine off is the way to go.
 

Engine off is the way to go. Take a look at the daily mpg thread or some of dan's or darin's (metrompg) threads on driving technique. They're fantastic chaps.

i can floor it and still get
 

i can floor it and still get 50 mpg thanks to engine off technique over a span of 10 miles driving with a dead cold engine with temps at 15 degrees C.

.2 gallons burned or .8 liters.

Re: that's amazing - nice
 

the comments so far are right. city driving just gives you more options for being efficient than hwy driving. there are more cards you can play, and one of the biggest is engine-off coasting. at least around here, the highways don't offer many opportunities to coast.

a few times lately i have been getting higher mileage on round trips of in-town driving than i can get at *any* steady speed in top gear (even 80+ mpg in 5th at 55 km/h).

Re: that's amazing - nice
 

I have to insert that this may not be true for automatics -- I've found my best mileage cruising at 55, with city driving being the killer. Even with engine-off coasting and/or neutral at the stoplights, it just takes too much energy to get going again (that's with a ease into 20% throttle until desired speed). Any other automatic folks with the same problem? If I did highway driving all day I could get in the high 50's.

Re: that's amazing - nice
 

if you conserved your momentum for the red light, that number wouldn't be as low ;) 1st gear starts the worse FE killers ever. If you can trick your car into thinking to start out in 2nd, things could get better.

Or go on that road slower yes, even slower so that you don't even have to conserve momentum when you reach the light. The light will turn green for you!

Quote:if you conserved your
 

The problems with automatics, my main man, are that so much of the power the engine creates is lost on the way to the wheels, which makes accelerating really really ****ty. Also, you cannot control your shift points or kill the injectors at all on deceleration. It's a bad game, lucky I'm getting out of it.

Re: that's amazing - nice
 

you may be right. my mom's camry doesn't shift into high gear until 80 km/h (around 50 mph). no way to short-shift an automatic.

that said, i've never done any FE-measured driving in an automatic, using engine-off coasting. until i did, i wouldn't be convinced that you *can't* beat highway figures with it (and other in-town techniques).

If i baby it my car shifts
 

If i baby it my car shifts into high gear at 34mph.

Can't time lights
 

The problem is, I can't time the lights on the Missouri side of town -- if a car is waiting at the light, it could change, or it could stay green. What kills me, is when 3rd is pefect to accelerate slowly, and it kicks-down to second. Dammit! I have 1st and 2nd lock, so I can start in 2nd if I felt like it, but after that, the automatic Gods render free-will useless. I end up stopping and going often, but I'm getting the engine-off coasting down. I just have to keep an "eagle eye" on the opposing lane and startup at yellow and get in gear or else I've got honking maniacs on the backdoor.

Story hour: If I didn't have to race to get a family member's birthday cake, I'd be at 40, but now I'm down to 36. There's some hope left: 1/2 tank. On the same day my in-laws were following me to a b-day get-together. I started into an intersection on a green light (slowly I may add) and some #$*@ in an SUV ran the red light and nearly totalled Teggy, and maybe me. If I didn't use the peripheral vision to check if my in-laws were behind me, I wouldn't have the crazy SUV biatch, and I'd be looking for a new car from the hospital. She gave ME the finger, saw my light was green, then took off. My father-in-law about had a heart attack because he saw the whole thing unfold behind me. There were mere inches between matter occupying the same space. I hit the brakes hard and used the ABS to maneuver around the skidding SUV. My blood pressure consequently went through the roof. Then we all went for miniature golf, and all was right with the world. 3 over par aint bad.

Pictures to the Hot Air
 

Pictures to the Hot Air Intake
https://www.saturnfans.com/photos/showgallery.php?mcats=all&si=hot+air+intake&what=a llfields&name=&when=0&whenterm=&condition=and

What year sl2 do you have?
 

What year sl2 do you have? After looking at your photo gallery it seems to be a 91 or 92 auto. That intake looks like it could melt. Plastic that close to the header could be dangerous..

Here are the pics of my hot
 

Here are the pics of my hot air intake, and one of the IAT resistance table.

https://www.saturnfans.com/photos/showgallery.php/cat/500/ppuser/20223

A guess on the heated fuel/heated air type of mod is that you'd probably want to keep the air temps below 110-120 F or so in order not to reduce power too much...but also heat the fuel to around 135F...maybe up to 150F to gain mileage. I've tested this to increase mpg and power by around 10% or so.

Reasoning is that heating the air too much reduces available oxygen...while heated the fuel results in improved vaporization...since the fuel is what needs to vaporize.

I also think that maybe closing the extra air openings (other than the rad opening) causes higher engine/fuel temps that increase mileage...rather than it being an aerodynamic effect.

With an EFI car that recirculates the gas constantly thru the gas tank...I insulated the bottom 2/3s of the tank with some thin closed cell insulation and got maybe a 10 F rise in fuel temps. Also blocked the extra openings in the front to increase engine bay temps. Plus I pull air from behind the rad...intake temps around 100-110F.

All this is still in the testing stage though. Just thought I throw out the ideas....

Somebody needs to check the shift points in an automatic with a vacuum gauge to see if it is being controlled by engine vacuum. I think it is pump pressure in the automatic and that requires tapping into the transmission with a pressure gauge to figure out when the shifting occurs. Either way you guys over 50mpg are doing great. Wish my Geo was road worthy to test some acetone and aero mods with.

Are you using a wideband O2 or just checking your cars narrowband?

Why no o2?

this was directed to cheapybob, dunno why u responded?

I am trying to figure out how fooling the ecu that the intake temp is hot helps, does it lean out the mixture?

I have an A/F meter. It doesn't run too lean. I heat the air up to about 200. Anything over that is bad. Same with water temp up to about 205, over that is bad. Once its warmed up, I cheat the computer with a resistor network on a switch and tell it the air is 247, but its really only 200. I need to rig a cold air intake to sense when the air is over 200 and mix in some cold air and keep the temp at or under 200. It might be nice if it activated under heavy throttle conditions, too. Ignition retards if the actual air gets over 200, killing mpg gains.

Found out my scangage was off. So when I thought I got 59 mpg it was really on 56.

On a Saturn anyhow, the ECU leans out the mixture as the air temp increases.

I don't know how accurate your narrowband read out is. Most the forced induction community calls them a light show. https://www.honda-tech.com/zerothread?id=1001592

How bout on a Honda?

How do you keep the fan from kicking on? Mine kicks on at 195 I though about getting high thermostat but I am at 185 now and I could go to 190 if I go to 195 it might make my fan kick on all the time.

Narrowbands suck.

Anyway, it doesn't lean it out, just corrects the fuel multiplier. Hondas do also, search for my post called "a tidbit on iats" or something like that.

I heard of someone switching to Evans coolant that encountered this problem, they solved it by putting a resistor in-line with the fan control. Here is a link to Evans. https://www.evanscooling.com/main1.htm It is a waterless coolant and it doesn't need to be pressurized so you can run the engine much hotter for better efficiency.

I don't have $300 for a wideband sensor. I'm getting good MPG's, my plugs look ok, and my narrowband sensor says I'm not running lean, so i'll just leave it be.

As for the fan, I have a Saturn SC1, and the fan doesn't come on until about 219 or 220. Thats a stock setting.

Hi Bob, What is a hot air intake and is the resistor you cite 105 ohms or 150? I have a '96 sc2 w/ dohc and i'm trying to improve the mileage. Thanks.