remove exaust resonator for mpg?
 

my echo has a cat,,,then a resonator,,,,,then a muffler, if i were to replace the resonator with a pipe ,,, i know the noise would go up , but would there be any mpg increase? i dont want to sound like a ricer, but for enough fe i will do it ,,,anybody done this, or have ideas?

My idea is it won't be effective enough for you to tell.

But don't let that stop you. If you have a better means of testing fe than tank-to-tank, put a test pipe in there and try it. Make sure you do an airtight test or we'll rip it apart.

IMO not worth it. Us ecodrivers never use the engine to the extent that needs maximum flow (high engine loads and high rpm).

do not remove the resonator
 

alot of times resonator deals with more than noise, it sets a speed bump for the catatlyst. It is even a set distance from the cat by good engineers. it is often a chamber to allow a quick burp, then slow...to make the cat REALLY function. Every off throttle, and on throttle.
on injecteds with air bypass, the exhaust is not bothered much, with or without,hence the resonator hack on modern turbo cars..it is screaming through the pipes anyway at all times there. For n/a cars, it needs math.

I went into quite an experiment deciphering exhaust for a low pressure carbed car...the highest mpg on planet earth - (for you metrompg) :thumbup:

it still needed a resonator, but nearly hollow, to mimick what fat injected intakes do for the catalyst. The echo could take a more open baffled one and possibly increase mileage, but unlikely. Exhaust Too hot is a good sign to mess with resonator.

Try it it's only 40 bucks, We did it on our '91 190 E and i didn't really pay attention to FE before and after but it had a little more throttle response, and if it works then you'll have another thing on here that people can do for cheap and it's not Reeeeally loud it just makes your car a little deeper, especially with stock exhaust

Just throwing one thing out there, considering your torque usually comes in low 1500-3000 RPM that's the range most of us ecodrivers are in right? I'd say when the engine is producing full torque it probably pushes a bit of air through the exhaust too SO it may be beneficial there

Why are you giving the O.P. advice if you have no idea if it will help or hinder achieving his fuel economy goal?

I removed my cat a long time ago, but left all resonator pipes. I had increased throttle response, it seemed to take less throttle, and the noise (out the exhaust pipe) did not increase at all...

I only ever put the cat back on the car for getting it inspected.

haha...yeah you do.

Because we did it on our car and i told him the results, i didn't monitor before after FE results but looking at the mileage on that car I'd say it helped out a little, especially since less throttle is needed to achieve the same speed that extra throttle response can sometime save a bit of gas

Sorry Domman, you just don't get it. You keep saying less throttle is better for FE, but you apparently don't understand how engine efficiency works. More throttle means more efficiency. This is why pulse and glide works so amazingly well. Its also why you drop down engine size to increase mileage. Using your theory that less throttle is better, I should drop a 350 in my Paseo for as little throttle as possible while cruising. Seriously, you need to read up on brake specific fuel consumption and stop giving bad info to people.