Dual Exhaust

2006 Toyota Tundra p/u. Want to know if there is any advantage to installing dual exhaust. I kow it sounds cool, but would it help with gas mileage and or performance.

Won’t help mileage, may (very) slightly help power, but at a cost of noise - makes it sound faster, even if it isn’t!

If it is a cat-back system then no. You would need to upgrade the entire exhaust system and even then the improvement would be negligible.

30 years ago it could actually add 25-50 hp…But today…there is NO ADVANTAGE WHAT-SO-EVER. It may sound cool and look cool…but that’s it.

If you only do stop and go driving with short trips, dual exhausts will rust out your system much quicker, since it never warms up enought to drive out the water.

It’s really just a sound thing these days. Engineers have learned over the past decade to engineer every drop of performance they need out of factory systems while keeping things quiet. It used to be a big help to open up exhausts (Massive gains on 70’s vehicles) but now it’s almost pointless unless you want a loud vehicle. My adivce is save the cash.

On my car it the difference between single and dual is about 15 hp. With others it might be a little more or it might be nothing. It really depends on the vehicle.

I just read an article on this subject in an off-road vehicle magazine. They replaced the standard exhaust on a 2005 F-150 with a Dynomax cat back system. I have no idea how much it cost, but the dyno readings showed a horsepower increase at the rear wheels of almost 18 hp, an increase of 18 lb. ft. of torque, and an increase of about .5 mpg. The test methodology seemed reasonable, using an Edge Evolution programmer to test actual gas consumption, the same brand of 87-octane gas, and over 500 miles of test driving. I have no idea how much such a setup would cost, but it is interesting to note that the manufacturer said that there was no notable difference between the single and dual exhaust versions. The downside (for some) is that the after-market system is somewhat louder and resonates at certain speeds.

Sound? That is a very personal choice. I like my cars quiet.

Performance? Maybe some slight performance gain at full throttle. Anything less will not get you anything more. Modern cars seldom gain much of anything with an exhaust mod. They are deigned well to start unlike the cars from the 50’s & 60’s.

Mileage increase likely will be too small to measure. In a few cases it can even reduce mileage.

The bean counters have the final say. There are more than a few cars the benefit from dual exhuast, The Crown Vic/Grand Marquis gains 15 HP, The newer GM SUV’s (Arcadia/Enclave/Outlook) have an optional dual exhaust that adds a few HP. Mustang’s with the 302 respond very well to exhaust upgrades. Just about any vehicle with forced induction will see an improvement with a good exhaust upgrade.