Electric Exhaust Cutouts? [and other efficiency mods]

[maplesyrupghost]

Originally Posted by sarguy01

If you want to spend your money, then spend it, after all, it is your money! You already have it spent in your head anyway.

But, if you want to get better mileage, then don't buy anything. You don't need to. You only need to mod the driver as a first step.

I already hypermile as I drive, got that under control.

If I wanted to save a few bucks, I could just keep lugging myself to work in the 36 mpg Accord. I would save about $5 in fuel per day. It's kind of rediculous to drive the Vitara since there are obvious savings on a day-to-day basis if I don't. I have invested too much into the Vitara to just not use it, though, so I'm willing to invest a bit more into it if I can squeeze 33-35 mpg out of it. Basically what does it cost to make a Vitara as efficient as an Accord. It's not far off.

Right now the goal is to spend an extra grand or two on the Vitara so that it will be as good as it can be. Not to save an extra grand or two or somehow come out at a net gain, but just so that I can have one vehicle for both summertime and wintertime daily driving. If I drive the Vitara every day instead of the Accord, it would cost me as much as $1300 a year more.

Now, you say if I want to get better mileage, then don't buy anything. I'm already, "perfect"? Not true. It has a mechanical engine fan. For $100-200 I can get everything I need to convert it to an electric fan, guaranteed to gain in MPG. So right there is a situation where I DO need to buy things to get better mileage. The question now is what else is there, in a budget of $2000, to gain me 5-8 MPG? If $200 is allocated towards the engine fan stuff, $300-500 in ECU tuning stuff, $50 on a spare ECU for modding, I would still have $1200 - $1400 left. Trying to get the most MPG per dollar, without making the truck look or feel rediculous. Fuel efficient tires would be nice, but I need winter tires already and my summer tires are good for 2 or 3 seasons still. Not looking in that area, but in terms of aerodynamics, there is a lot I can do. Under belly pans are common, they seem to help a lot and they look great because you don't see them! I would even like to believe that changing my mirrors from this shape:



To this shape:



Will be technically more aerodynamic. They are both OEM mirror choices for this year, not even an aftermarket part.

There are things out there to make it more efficient. I'm just trying to figure out all my options.

[LittleDoc]

I installed cutout between cat and muffler with pipe to near rear axle. Quiet at freeway speeds and acceptable around town. I have seen about 3/4 mpg improvement averaged over 8 tanks of gas. Unfortunately I installed a new cat at same time so have no idea at this time as to relative improvement due cutout vs cat. Simple Otto cycle analysis supports improvement at both WOT and part throttle due reduction in pumping losses.

[Frank Lee]

You can't change multiple items at once then attribute "results" to any one thing.

"Quiet"- sure, from your perspective. What about those outside the vehicle? Including those who might be trying to nap or some such.

[MobilOne]

In Winnipeg, could you just run without a fan?

[LittleDoc]

Originally Posted by Frank Lee

You can't change multiple items at once then attribute "results" to any one thing.

"Quiet"- sure, from your perspective. What about those outside the vehicle? Including those who might be trying to nap or some such.

I agree that is why I mentioned I had changed two things. I plan to close the cutout and check mileage so I can tell how much is due the new cat.
Re quietness, I have been watching pedestrians and they do not turn and look at me or otherwise react. I realize this is crude test and I recognize that the truck is nosier than stock. My point is that with the after cat cutout and tail pipe to the rear axle, it is surprisingly quiet.

[NoD~]

I had a cutout on my Neon long ago, right off the header, before the cat. The idle was awesomely rumbly and the sound at low RPM was insane. But, it was loud. Super loud. No idea on MPG. Car wasn't built for MPG at the time.

As for a cutout AFTER a cat? I could easily see that as fairly quiet. It's amazing how much muffling the cat can actually do. I've had several different types of "race" setups with different exhausts and after trying cat only, I can verify that a cat can muffle enough and, pending the vehicle, a car can be as quiet, or quieter, than some of those fart cans I've heard around town.

Now I'm just on stock exhaust, minus the short tube header I have on. Don't really miss anything fancier. It's just perfectly quiet... and cheaper.

[oil pan 4]

I am going to run cutouts on my bored and stroked 454.
The engine is intentionally getting a restrictive exhaust to encourage reversion at cruse speed.
That way I don't run a super wide open exhaust all the time allowing fuel and air to fly right through the engine.

[Frank Lee]

So who gets to be blessed by that musical ambiance? :/

[oil pan 4]

The 11:1 compression 489 cubic inch big block chevy with 270 grind hydraulic roller should sound like the world is ending to anyone with in 50 feet when the cut outs are opened and the gas pushed to the floor.
But the good thing about them is they should stay closed around 99% of the time.

[Frank Lee]

So who gets to be blessed by that musical ambiance? :/