From my searches the subject of exhaust gets beat to death but it seems like it is always about the sound. Sure I don't want to ruin my sound, but to me the most important question is whether or not I can get an exhaust upgrade that will improve power without killing fuel economy. The second question would be whether I'm willing to put up with a potentially undesirable sound.

Has anyone ran before and after dyno comparisons of any exhaust? Has anyone compared brands (I know I'm reaching, but this is an established group)?

TIA,
~ Fred

 

The usual round of questioning: What year? What engine? ....we need details to really answer the question, but in general exhaust is a mod that you can gain power from and sometimes even gain mpg, its all about improving the efficiency of the engine.

 

Rats! And I should know better than that too...

It's a 2004 with 3.4L, and I added this to my sig so I can't forget in the future!

~ Fred

 

umm...you mean 4.0? the 3.4s were in the third gen. Anywho, generally intake and exhaust mods will not decrease gas mileage. Factory pieces tend to be fairly restrictive so you're basically just improving on the original design. With intake you actually tend to increase the VE(volumetric efficiency) of the engine.

 

The current TACOMA still has the 3.4 AFAIK.

 

So I may have kinda sorta missed that in the sig.....

 

yes, the 2k4 taco has the 3.4L... the 2005 will have the 4.0L....

As to answer the question, assuming your driving habits were to remain the same, fuel efficiency would at least stay the same, if not slightly improve with the increased flow of the intake and exhaust. However, as you pointed out, exhaust and intakes are mostly done for the sound, so people will be more heavy-footed on the accelerator in order to hear their newest investment -- this leads to a decrease in fuel economy.

As for a comparison between exhausts, I believe dynomax and magnaflow come in top for performance... Although I can't stand the magnaflow... sounds ricey to me.

 

So the general consensus is that a replacement muffler offers better gains than an entire cat-back system?

If that is true then that is awesome, considering the price difference. But I would have expected that any mandrel bent system would out-perform an exhaust with crimped bends -- even if they are the same diameter (research on this and other sites tells me most replacement systems are the same as OEM in diameter). Would it then hold true that the Magnaflow cat-back should offer the highest performance gain?

~ Fred