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Eco modding ideas?

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t_squared212

Probationary Member
18
5
Feb 8, 2019
Dubuque, Iowa
I'm putting away my talon for the winter (trying to avoid salt). So I'm starting to mull around ideas for what to do when I take it out in the spring.
Ever since I've gotten the car I've heard/read that the car will never be fast without completely building the engine and even then it won't compete. Thats not my style anyway so I'm looking into ideas for maxing out fuel efficiency as much as I can. Its a fun car to drive and I have been and will daily drive the car and take it on a few road trips throughout the spring summer and fall.
So, what are some things I should consider for eco modding? These are some of the ideas I have. I'm just looking for more thoughts, suggestions, and such to help out. Thanks in advance!

edit: it’s a 1997 talon esi with 420a engine non turbo

Lightweight rims, AC delete, rear seat delete and replace with lightweight floor and carpet (sheet metal or mdf board)
light weight body parts (possibly carbon hood and hatch since both are a bit damaged)
 
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So are you looking to have better performance or just solely get better gas mileage? Because some mods that achieve one will negate the other.

I've heard that cold air intakes can slightly improve gas mileage, along with horsepower gains.

Also setting your plug gap a little larger (max 0.046") can get you better gas mileage and horsepower gains
 
Did you just say that a built 4G63 won’t compete? Won’t compete with what? Sorry if I misread that but...
You seem to have read that right. The Red Demon would like to have a word with him.
 
I've heard that cold air intakes can slightly improve gas mileage, along with horsepower gains.

Hot air typically gets you better gas mileage. Lots of modern cars have heater cores in the intake box to heat up the air before it gets to the engine to increase fuel economy.
 
Sorry should have been clear, it’s the 420a engine.

Did you just say that a built 4G63 won’t compete? Won’t compete with what? Sorry if I misread that but...
Sorry, wasn’t clear. It’s a 420a engine.

So are you looking to have better performance or just solely get better gas mileage? Because some mods that achieve one will negate the other.

I've heard that cold air intakes can slightly improve gas mileage, along with horsepower gains.

Also setting your plug gap a little larger (max 0.046") can get you better gas mileage and horsepower gains

looking for fuel economy while keeping it fun to drive. I know it’s not a race winner but I’m just looking to get entertainment out of it for myself.
 
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In my opinion do not delete comfort items. It will be less fun. If you want fun get some good tires assuming you don't already have some. Also adding mods for mileage is a losing proposition. You will never break even. Tires alone will increase fun factor.
Any meaningful gains in fuel economy will cost more than you will save. At the cars price point i would just drive it. Add what makes you happy.
As always to each his own.
 
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I agree, don't delete comfort items, and don't spend money hunting for MPGs in a DSM. It's not a light car and it doesn't have a modern engine or management system, nor does it have fantastic aerodynamics. There are tiny things you can do, but most of them compromise safety and/or comfort. Just keep the car maintained and be as light on the gas pedal as you can.
 
tbh, weight savings usually is either expensive, or involves getting rid of comfort items. If it were my car and I wanted to max the MPG I would look into things like running the lightest weight oil that is appropriate, and tuning the car to make sure it’s not running overly rich and burning excess fuel.
 
Driver mod is a big one for improving fuel economy. See: How To Save Gas

Also, a vehicle that is caught up on all maintenance, not just engine and transmission maintenance, but also free of check engine lights or DTCs will be a better candidate for improved fuel economy.
 
How important are maintaining aesthetics to you? I have this thought with every one of my cars. What can I do to improve economy without changing the aesthetics or reducing performance. There really isn't any low hanging fruit on any fairly modern car aside from changing driving habits. I bumped the Miata from 34 mpg to 46 mpg on one of my road trips by following an EV most of the way and slowing down.

Smoothing out airflow under the car can help. Cover the bottom of the engine bay with something smooth, then do the same at the back to smooth out the spot between the gas tank and the rear bumper. A lot of efficiency is lost by air getting trapped inside the rear bumper. If the car's underside is appropriately smooth, the tall factory ride height will actually help fuel economy by allowing the kammback effect to extend farther behind the car. It's weirdly counter-intuitive, but that's a reason why EVs have lots of ground clearance.

The engine bay is a big scoop/parachute at the front of the car. You want to direct as much air around the bumper as possible and as little through it as is necessary. Assuming you've got sufficient cooling for your needs, start blocking off the grille opening and any other openings into the engine bay.

A rear spoiler could help a lot with aero but us mere mortals aren't capable of designing an effective one. That takes pretty extensive modeling, and you have to tune it to a specific speed. I have no idea if any of the Eclipse or Talon factory spoilers would help or hurt here, or what a better design would be.

Skinny, hard tires are better for fuel economy, but the trade-offs are always way worse than the economy improvement. What one could do, though, is pair lower grip tires with a beefy rear sway bar to give the car some fun handling characteristics beyond the standard understeer. Unless you want to go that route, I wouldn't mess with economy tires at all. If you're thinking about wheels anyway, you should go as small in diameter that you can and give yourself a nice, big sidewall. In theory, solid wheels are more aerodynamic than ones with large holes, but actual results are too dependent on the aero of the fenders and the rest of the car to know whether something like wheel covers would help or not.

As others have said, do not delete comfort items. I've had a few cars that I all but stopped driving after removing comfort items that had broken. Having a fun car that gets bad fuel economy is way better than an efficient car that you don't want to drive.

A lightweight battery is always an option if you are comfortable with its compromises, and relocation to the rear is not a bad idea.
 
How important are maintaining aesthetics to you? I have this thought with every one of my cars. What can I do to improve economy without changing the aesthetics or reducing performance. There really isn't any low hanging fruit on any fairly modern car aside from changing driving habits. I bumped the Miata from 34 mpg to 46 mpg on one of my road trips by following an EV most of the way and slowing down.

Smoothing out airflow under the car can help. Cover the bottom of the engine bay with something smooth, then do the same at the back to smooth out the spot between the gas tank and the rear bumper. A lot of efficiency is lost by air getting trapped inside the rear bumper. If the car's underside is appropriately smooth, the tall factory ride height will actually help fuel economy by allowing the kammback effect to extend farther behind the car. It's weirdly counter-intuitive, but that's a reason why EVs have lots of ground clearance.

The engine bay is a big scoop/parachute at the front of the car. You want to direct as much air around the bumper as possible and as little through it as is necessary. Assuming you've got sufficient cooling for your needs, start blocking off the grille opening and any other openings into the engine bay.

A rear spoiler could help a lot with aero but us mere mortals aren't capable of designing an effective one. That takes pretty extensive modeling, and you have to tune it to a specific speed. I have no idea if any of the Eclipse or Talon factory spoilers would help or hurt here, or what a better design would be.

Skinny, hard tires are better for fuel economy, but the trade-offs are always way worse than the economy improvement. What one could do, though, is pair lower grip tires with a beefy rear sway bar to give the car some fun handling characteristics beyond the standard understeer. Unless you want to go that route, I wouldn't mess with economy tires at all. If you're thinking about wheels anyway, you should go as small in diameter that you can and give yourself a nice, big sidewall. In theory, solid wheels are more aerodynamic than ones with large holes, but actual results are too dependent on the aero of the fenders and the rest of the car to know whether something like wheel covers would help or not.

As others have said, do not delete comfort items. I've had a few cars that I all but stopped driving after removing comfort items that had broken. Having a fun car that gets bad fuel economy is way better than an efficient car that you don't want to drive.

A lightweight battery is always an option if you are comfortable with its compromises, and relocation to the rear is not a bad idea.

Thanks for the help. I'm only taking out the rear seat and redoing the hatch floor. I'll keep the interior bits so if I ever sell the car, the next owner can decide what to do with them. The interior is going to stay stock or near stock from the seat forward. As far as the AC goes, it doesn't work. (car sat for several years and I have no idea if it worked before)
 
Not that I doubt you, since the 420a isn’t my platform, but Syked Performance in Washington State seems to think they can tune a stock 2G 420a.
Everybody that doesn't know anything about the platform thinks they can tune it. Call around and ask, almost everybody thinks they can.

But the reality is, our gel filled Chrysler restricted ecu cannot be tuned in any form or fashion. You can view live data about engine parameters, but cannot adjust the values.

Hot air typically gets you better gas mileage.
90% of the aftermarket intakes for the 420a are actually sucking in hot air. I had to custon build my intake, not only because of my upgraded throttle body, but also because the aftermarket one I bought was routed right behind the radiator next to the headers.

You would have to buy the long intake to actually get cooler air. It is routed near the bottom of the bumper.
 
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Everybody that doesn't know anything about the platform thinks they can tune it. Call around and ask, almost everybody thinks they can.

But the reality is, our gel filled Chrysler restricted ecu cannot be tuned in any form or fashion. You can view live data about engine parameters, but cannot adjust the values.
Apparently this guy got his hands on a legitimate programming tool used by Chrysler engineers and can indeed change the values inside these ECU's. To what degree they can be changed, or how effective it is overall, I don't know. He's been pretty tight-lipped about it all, but this is old news and it has been verified. I suspect there are some inherent limitations to the stock hardware that still make aftermarket systems appealing.
 
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