Anyone out there actuall increased their performance, low end or mpg when adding dual exhaust?
Are they all going to give you less throttle respose?
I though they were called performance exhaust for a reason.
So they dont actually help the performance?
Dont know alot about exhauss so any info would be great.
Looking for better sound, performance and mpg
thanks

I highly recommend reading through the sticky here about building a proper exhaust system (yes...all 11 or so pages) It is very, very insightful. I too am pretty novice on the whole subject of exhaust, and reading through it, upped my understanding 10 fold......based solely on what I've read in the last day or so, I'd say you are experiencing an increase in backpressure which is hurting your performance (I am assuming that you went with piping larger than factory)....if you read the sticky, there is some explaination as to how the backpressure increases even though you went to a larger diameter pipe....deals with scavenging of the exhaust gases.
later!

the stock system was designed with optimal pipe sizes for efficiency. you can gain a little by replacing the muffler to a more free flowing design. the factory only used the poor flow muffler because they wanted zero noise.

i installed a dual in/dual out magnaflow 12468 to my 5.7 w/ 2.5 pipes and at 1st i lost torque and the pick up was lame.. i read online to remove the battery terminals for 30 mins or so and it worked. now i can peel off and the gear changes are so smooth, dont feel the gear change..

i just wish the myffler would sound louder. will going to 2 1/4 pipe make the sound louder or growl more?

i installed a dual in/dual out magnaflow 12468 to my 5.7 w/ 2.5 pipes and at 1st i lost torque and the pick up was lame.. i read online to remove the battery terminals for 30 mins or so and it worked. now i can peel off and the gear changes are so smooth, dont feel the gear change..

i just wish the myffler would sound louder. will going to 2 1/4 pipe make the sound louder or growl more?

If you go with a shorter muffler with smaller inlets, it should be louder and better for performance. Don't expect to get the same low end torque as stock though because without a proper tuner there is no way you will beat stock for mpg and performance.

i was planning on going to the shop were i got it installed and see if they can do a 2 1/4 pipe, you thinnk that would help?

Sorry im new into the TS and in modifyng vehs, what is a good tuner mean?


If you go with a shorter muffler with smaller inlets, it should be louder and better for performance. Don't expect to get the same low end torque as stock though because without a proper tuner there is no way you will beat stock for mpg and performance.

I got rear ended by a Civic (really sucked for him) and he went so far under, he tweaked the exhaust. I decided to go with Magnaflow, since I really didn't care about sounding like I had a '67 Chevy.

They have been awesome!!!

A lot more umph when I need it, not too much when I don't, and they sound great too. Not loud, just a deeper purr.

MPG went up maybe 1-3.

All in all, a great way to spend the $320 bucks.

Oh yeah, the guy used 2 1/2" pipe from the muffler back.

Also, the pipe usually comes over the rear axle and then makes a sharp left and comes out behind the pass. side mud flap. I had the guy come straight back after the axle with maybe a 5% decline and right at the spare, it it has a 45 degree bend, which he cut parallel to the ground. It's completely invisible. It's awesome. I love it.

Oh yeah, I have the 4.0 V6 and a single in / single out Magnaflow.

i was planning on going to the shop were i got it installed and see if they can do a 2 1/4 pipe, you thinnk that would help?

Sorry im new into the TS and in modifyng vehs, what is a good tuner mean?
I'm no expert but I had a magnaflow 28" long body with 2.5" inlets/outlets (I read that this muffler is designed for large engines, somewhere 6.0 and up). The pipes going into the muffler were noticeably smaller than the inlets diameter so I would say it won't matter if you make the piping smaller, your gonna need a new muffler with smaller inlets/outlets to make a difference IMO. Key is to stay as close to stock diameters as possible. Here is a thread with some old pics of my exhaust http://www.tundrasolutions.com/forums/performance-exhaust-systems/196303-should-i-spend-to-fix-exhaust/

Also I experienced the same performance loss as you so I just ended up going with corsa exhaust.

A tuner is something to change the parameters in the engines computer to compensate for a new performance mod. Right now there is no tuner for the tundra so any mod will be at the mercy of ecu adjusting itself slightly which isn't enough to change anything (like unpluging your battery, it makes it better but the ecu won't let the stock parameters change much at all). Some will argue that Unichip works as a tuner but I say it is not since it is just a plug in device fooling your computer into doing something it's not supposed to (for example add more fuel).

thanks for the info. When you switched to Corsa, did you gain the torque that was lost?

thanks for the info on the tuner as well.

Did you instally any CAI or any type of intake on the tundra? I here people say its beneficial and some say it's not.



I'm no expert but I had a magnaflow 28" long body with 2.5" inlets/outlets (I read that this muffler is designed for large engines, somewhere 6.0 and up). The pipes going into the muffler were noticeably smaller than the inlets diameter so I would say it won't matter if you make the piping smaller, your gonna need a new muffler with smaller inlets/outlets to make a difference IMO. Key is to stay as close to stock diameters as possible. Here is a thread with some old pics of my exhaust http://www.tundrasolutions.com/forums/performance-exhaust-systems/196303-should-i-spend-to-fix-exhaust/

Also I experienced the same performance loss as you so I just ended up going with corsa exhaust.

A tuner is something to change the parameters in the engines computer to compensate for a new performance mod. Right now there is no tuner for the tundra so any mod will be at the mercy of ecu adjusting itself slightly which isn't enough to change anything (like unpluging your battery, it makes it better but the ecu won't let the stock parameters change much at all). Some will argue that Unichip works as a tuner but I say it is not since it is just a plug in device fooling your computer into doing something it's not supposed to (for example add more fuel).

I ordered the TRD dual cat-back and will get it next week.
I will watch for mileage change and seat-of-my-pants torque test.
Hopefully I can control myself with the throttle and not ruin my mileage :)