TRD cat-back duel exhaust and power...

[Brian's Toy]

I've read at least one or two posts in the past where people have said that installing a cat-back exhaust actually robs some torque from a stock 4.7 Tundra. I see how it may happen but who knows... Toyota claims 3 extra horsepower, but they also claim 3 extra horsepower using a TRD exhaust on a Camry V6, so that just may be a marketing number.

I've had my TRD duels in for 2 years now and it's hard to tell much of a difference; I wish I knew someone with a stock exhaust on a Tundra for me to drive as a comparison.

Has anyone directly observed a power difference; dyno results or a good calibrated seat of the pants result with the two. It would be interesting to know...

Brian

[arkie6]

I can't really tell any +/- difference down low, but above 3000 rpms there is a noticable added rush of power in my 2000 V8 4x4 with the TRD duals. I thought Toyota claimed closer to 10 hp increase (peak) with the TRD duals and about 5 hp increase with the single. I can still spin my tires under the same conditions that I could with the stock exhaust and my gas mileage is about the same and since your engine spends most of its time at <2500 rpm, it doesn't appear to me that there has been any measurable effect at the lower RPMs, at least in my case. Others have posted different experiences, but I don't believe anybody has posted any dyno numbers, just how they "feel".

[cubic22]

Would yall recommend the TRD -xhaust for non-TRD tundras?

If yes, why?



If no, what would you recommend?

2002 V8 Access Cab 4X2

[Red Hornet]

One off road mag claimed 1-pony per cylinder, or about 8-horse increase with the TRD duals.

If you'd been driving an old 1991 Toy V6 truck with 150 lame pony's, about 15 them already out to pasture, ten refusing to pull, three wanting to ride in the bed, you'd say the Tundra was quick, TRD or NO.

The Hornet seen an increase of about ~ 2.5% MPG increase with TRD duals, Ramona Chevron 87 as always. Thanks Steve G. @ Carson way up there in LA Land.

Cheers,
-RH

[v8Toilet]

I tried the TRD duals and my story is different. At about 25k miles I installed the TRD duals and immediately noticed that I lost the low-end snap that my engine once had. Before the install I could spin the tires in a turn but after I couldn't spin them even in a turn. After two weeks I couldn’t stand it anymore so I went back to stock.

The problem is that the exhaust goes from one 2.25" pipe to two 2.25" pipes. This slows down the exhaust gas velocity and causes the motor to loose low-end torque. You might gain 3-8 top end horsepower but torque is what accelerates a vehicle and torque is what you feel and need in a pickup truck. I give the TRD dual exhaust a for power but a for sound and quality.

[Brian's Toy]

Interesting results, thanks all! Everyone's observation makes sense even though with different results. I guess the true answer would be with a dyno test before and after TRD duel installation,with both torque and HP results. Too bad TRD didn't post true test results with thier products.

Brian

[cubic22]

Can you ask for specified pipe sizes on dual exhausts or is what comes with the package standard?

I would like to hear some noise but keep the torque? is that possible?

[v8Toilet]

Originally posted by cubic22
Can you ask for specified pipe sizes on dual exhausts or is what comes with the package standard?

I would like to hear some noise but keep the torque? is that possible?

Yes if you go with a custom system. If you must have a dual exhaust I would run a Single inlet 2.25” muffler with two 1-7/8” dual pipes coming out the back or the same size as the pipes just after the catalytic converters.

You could also do what I did and just replace the stock muffler with the performance muffler of your choice and pick up a nice gain in low-end torque along with the sound you want.