Upgrade exhaust - Worse Performance

[Adverse2Change]

Is it possible for exhaust upgrades (when installed properly) to make driving performance worse (i.e. horsepower). I just got dual exhaust on mine with flowmaster mufflers. It sounds great and looks great, but I'm not sure that the performance improved. I haven't drivin' it enough yet to completely judge, but at times it feels to bog down some. Any thoughts?

 

[Roland69]

sometimes too much flow is not good. what size pipes did you use.

 

[Adverse2Change]

The design was to resemble the look of a Cobra/GT.... from the mufflers out I think it is 2.5". From the engine to the mufflers I think it is 2", but I would have to double check that. Here are some pics to better explain what I mean by resemble...

 

[big blue]

you probably lost low end torque. That would give a huge SOTP feel of being slower. That exhaust flows for a V-8 at 2.5" I would have gone 2.25"-2" with tips that were bigger.

 

[Adverse2Change]

Oohh I don't like the sounds of that... But I'll double check the exact size when I get home. I just assumed the installers would have known what they were doing.

If this is the case, is there anything to improve the situation other than swapping out pipes?

And as an aside, should I disconnect the battery and let the ECU reset itself? Could that be causing any flow problems?

 

[big blue]

You can put restricting pipes in where the catback goes. Other than doing a complete swap for smaller pipes there isn't much you can do without trying to bump the horse power from the engine. I'd say that that v-6 needs some back pressure.

As for clearing the ECU, I always unplug the computer for 30 min after installs. This resets everything and lets the computer start setting the new curves. You may well have more horsepower with your new setup you just won't feel it your normal driving range.

Just for example I put an SVO exhaust on my 2.3 hatch a while back and I lost all torque down low where I used it everyday. On the highway though I gained passing power(what little there is) and gained 3 mpg better over stock. It was sooooooooooo slow I just gave up and put a modified single exhaust on and I was back with better speed around town. With the changes I made it preformed just as well on the highway with similar to MPG rating.

 

[Adverse2Change]

You know, I'm almost wondering if this is all in my head. My wife doesn't notice any less power when she drives...but she doesn't really pay attention to that kind of thing. I did take a look underneath and some parts look almost 2.5" to 3". I couldnt get far under enough to actually measure, but it was rather large coming from the catalytic converter to where it splits off to each muffler.

I have to take the blame for assuming that the exhaust shop would install pipe sizing best suited for the car. I basically told them I want it to look like a cobra/gt's pipes and have a nice lil' growl (and most definitely not sound like a ricer!). Live and learn I guess...

 

[Tru_Blue_104]

I'd say live with it as is for the time being. A fix that you could maybe do, if you haven't already, is gears. That would deffinatly give you some more kick, and you wouldnt have to re-do your exhaust that you just paid for.

 

[zincyellow03]

I don't think that you would lose so much power that you would even notice it. By the way, interesting plates...

 

[Adverse2Change]

Well, I've been driving it a more and have gotten used to it, so whether it was in my head or not I've gotten used to it. I'll look into the gearing as well, no real rush though.

Zinc, those plates are fake

 

[Ernad]

get gears

 

[zincyellow03]

Well, I've been driving it a more and have gotten used to it, so whether it was in my head or not I've gotten used to it. I'll look into the gearing as well, no real rush though.

Zinc, those plates are fake

You got me!