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Discussion Starter #1
Alright, this may be a little weird, but does anyone know the best way to get more power without killing gas millage? I would think cold air intake. Gas is like crazy insane expensive and parts are expensive enough as it is without having to pay extra every time you fill up.
 

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get a bunch of after market parts(intake, exhaust, headers) to increase fuel efficiency..and just dont try to floor it at every stop light..your mpg should increase..but that usually does not happen since 99.9% of the people that mod their cars have a bad case of lead foot :lol:
 

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I'm sorry, you want to pay more money (over $500 easily) to save maybe 1 mpg (if its really true). Do you realize how long it would take you to recoop that money?

It would take about an entire tank to save one gallon. That would be about 200 tanks worth of gas, or about 25000 miles, to save that $500. Is it really worth it? And thats based on a $500 setup, which is a very liberal estimate. Almost 2 years before you break even, and most likely you'll try to sell the car before then, and the parts will decrease in residual value greatly.

I wouldn't recommend it. If you're chasing better mpg, sell the car...
 

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magoo said:
I'm sorry, you want to pay more money (over $500 easily) to save maybe 1 mpg (if its really true). Do you realize how long it would take you to recoop that money?

It would take about an entire tank to save one gallon. That would be about 200 tanks worth of gas, or about 25000 miles, to save that $500. Is it really worth it? And thats based on a $500 setup, which is a very liberal estimate. Almost 2 years before you break even, and most likely you'll try to sell the car before then, and the parts will decrease in residual value greatly.

I wouldn't recommend it. If you're chasing better mpg, sell the car...
He's not searching for MPGs, he just doesnt want them to suffer when he puts some bolt-ons on his car. He just wants a performance upgrade with no decrease in fuel efficiency.
 

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Discussion Starter #5
I didn't say I wanted to mod my car to increase gas millage, I said I wanted more power without decreasing mpg; the objective is more power not more mpgs. I was just wondering cause some people on here are getting like 13 mpg and that would be 7 mpg less then if you were getting 20mpg, but if, like you say, I would gain 1 mpg from a $500 mod, then the difference compared to the 13mpg guy would actually be 8 mpg, so if I drove 200 miles a week, then I would be using 15 gallons a week at 13mpg vs 9.5 gallons at 21. At $3.25/gallon the cost differenct would be $48 vs $30 per week, for the year $2496 vs $1560 (or $1690 if I had left the car untouched at 20mpgs), which comes out to a difference of $936 a year saved against the 13 mpg guy or $130 saved over stock. But like I said, I'm not trying to gain mpgs, I'm trying to gain power without paying for it at the gas station. Sooooooo, I would rather add a few parts for a modest power boost and maintain my mpgs than do something extreme.
 

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hmmmm lemme think.....more power without gas mileage going down...NOTHING!!!..I have a bunch of bolt ons on my car and let me tell you.....for a N/A car running 13 mpg is just fuked up. You got the number correct...I get 13 mpg with header/intake/exhaust/camgear/ and a tuned safc. It's pretty much logic...more power...more gas...less mileage...more fuked lol.
 

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that's sad. the IS is a 15 second car, yet our gas consumption is that of a v8 running 13 second timeslip. :lol:
 

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pinoyballah said:
get a bunch of after market parts(intake, exhaust, headers) to increase fuel efficiency..and just dont try to floor it at every stop light..your mpg should increase..but that usually does not happen since 99.9% of the people that mod their cars have a bad case of lead foot :lol:
This is what I was quoting.
 

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^^^

When you tune the SAFC don't you generally tune it leaner than stock?
Although the only point where the IS is rich is at WOT. At part throttle with the wideband hooked up, i got AF readings of 14.7, and at WOT 12.1 [that's what you want to lean out for more power.
 

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This just in

Power = Air + Fuel

You want more Power, you need more of each.

The only way to go faster without affecting fuel mileage is to take weight off the car, or the driveline (flywheel).
 

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Lol All this is so true. Only funny thing is on the highway since being modified. I averaged 28 MPG. That was on a 400 mile trip. Only thing different from sig was SRT intake and GReddy exhaust. That and no Valve body upgrade.
 

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Wookie said:
This just in

Power = Air + Fuel

You want more Power, you need more of each.

The only way to go faster without affecting fuel mileage is to take weight off the car, or the driveline (flywheel).
Agreed, weight reduction is the only thing you have. Although I read in the forums the Joe z intake along with after market drop in has improved mileage.

Flywheel is a double edged sword, u may accelerate faster but at same time when u shift ur rpms drop a lot faster too.
 

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Discussion Starter #14
Well, I'm not really an expert at anything, but from what I understand, or what I think I understand, is that gas mixed with colder air will ignite hotter or something, does that mean that you will burn more gas or burn the same amount of gas hotter? My understanding was that a cold air intake improves power by not just taking in more air, but taking in colder air to increase performance. If that is true then you could theoretically make your air colder, and increase performance without burning more gas. But like I said, I'm not really sure about that, which is why I'm asking ya'll.
 

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Colder air is more dense.

The more air you burn, the better. Dense means more air in the same space.

Its really negligible.
 

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2JZGEDrift said:
Flywheel is a double edged sword, u may accelerate faster but at same time when u shift ur rpms drop a lot faster too.
Do you have one? Cause it's really not that bad. Matter of fact, for city driving and typical slow shifting, I find my RPM's drop to the perfect point once the clutch is let back out.
 

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No, I know that when you want more power you need more of both fuel and air, but is it quite a dramatic drop? or just a couple of MPG's??
 

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Wookie said:
Do you have one? Cause it's really not that bad. Matter of fact, for city driving and typical slow shifting, I find my RPM's drop to the perfect point once the clutch is let back out.
I don't have one on the is300, but on my last car (B16A CRX), I had a Spoon flywheel (8.6lbs). I guess the experience is attributed to how much of a weight reduction there is. If the IS300 was shaved from about 30lbs to say 20 or so, it might work out to what you're experiencing - positive. My CRX one was reduced from about 20lbs to 8.6, and there were mad RPM drops even with a short shifter (then again I might just be $hitty driver).

Second difference can be due to the engine difference. The I6 who's peak power pt is in the middle range of the rpm band vs the Honda 4banger who's power comes only in the high end. With a lightened flywheel, RPM's may still drop faster but may drop into the right range (for the is300) whereas in a Honda it may drop out of the range.

Possibly for the IS300, a lightened flywheel is an advantage. BTW, what flywheel are you using - and parred with what clutch?
 
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