Your system is one of the exceptions I was thinking of when I wrote "nearly all". Certainly, a custom dual system like yours that has a properly located H-Crossover (or even better, X-Crossover) and exactly the right components including mandrel bent tubing usually can avoid low-end torque loss and will get improved torque in the higher RPMS. Although I gotta say, you might have done even better in the sub-3000 RPM range with the 2 inch pipe that was recommended by, IIRC, V8Toilet (and others) at the time you had your system designed/fabricated.
However, my remarks were targeted toward the typical folk like our original poster who buy an off-the-shelf "system" that simply replaces the stock muffler with a single inlet, dual outlet muffler (whether it be Flowmaster or TRD) and has dual 2.5 inch (or larger) pipes to the back of the truck. And when it comes to those off-the-shelf "systems", I'll stand by my statement that low end torque loss is all but guaranteed.
You are indeed proof that if someone wants to invest time, energy, and enough money to have a knowlegeable performance shop craft a custom crossover system, good to very good dual exhaust performance can be obtained. But most folk don't have that time, energy, or money...and won't get good performance from a bolt-on, off-the-shelf system that basically just replaces the stock muffler and single tailpipe with dual post-muffler tailpipes.
I will disagree and here is why. The 2.0 pipe has a thinner wall , and from the research and talking with experts the thicker gage wall on 2 1/4 will more then make up for heat losses compared to the smaller circumference pipe. Plus it last longer.
Since I'm getting a 2200 RPM stall with half or less the torque you guys have...and reports by various folk indicate that even full power trucks also have about a 2000 to 2500 RPM stall, I'd say stall speed is much more correlated to throttle postion and transmission turbine RPM than to engine torque.
Ray: My definition of Stall Speed differs from yours and Transdude's. My definition is, that it's the RPM the converter will allow the engine to obtain at WOT with the turbine locked. That's in gear with the foot planted on the brake pedal. That's the only definition I've ever known. To me it stands to reason that a more powerful engine might show a higher RPM under a stall test than a weaker one. Maybe I'm getting the terms stall speed and stall test confused? You need a bigger truck to pull that thing!
__________________ ADDING POWER HAS NEVER BEEN SO FAST!
Last edited by Dude Boy; 06-15-2004 at 07:27 PM.
Reason: Said "Tundradude" - meant "Transdude"
Ray: My definition of Stall Speed differs from yours and Tundradude's. My definition is, that it's the RPM the converter will allow the engine to obtain at WOT with the turbine locked. That's in gear with the foot planted on the brake pedal. That's the only definition I've ever known. To me it stands to reason that a more powerful engine might show a higher RPM under a stall test than a weaker one. Maybe I'm getting the terms stall speed and stall test confused? You need a bigger truck to pull that thing!
Naw, we're talking pretty much the same thing. For the first second or two after I floor the throttle under the above described conditions, the turbine is as good as locked with the brakes. Yeah, it's rotating, but at such a low RPM that it might as well be locked.
As for a bigger truck, not possible...the Tundra and the Dodge Dakota were the only two trucks that would fit in my garage as of last fall. I think now the new Chevy Colorado would as well. But the Tundra is stronger than either of those for towing and and I'm not remodeling my house to enlarge my garage!
To be honest, I probably would have to go to one of the 3/4 ton (or larger) domestics with a turbodiesel to get better low end torque. On my way home last Tuesday, I actually outran a Ford F250 while climbing toward the western approach to the Eisenhower tunnels...which is truly amazing since he didn't have a trailer in tow and I did! The driver (from Arkansas) was clearly flabbergasted that I was slowly but steadily leaving him way behind on that grade.
And on another climb, I literally blew by an older F150 with just a dinky little 1500 lb popup in tow...that Ford driver literally had his head hanging out the window to see what kind of truck was leaving him behind while pulling a much bigger trailer.
I had the TRD duals. The tips began to rust on the "TRD" etching, and I could not get it off. Then the connectors rusted at the cat. after just two years.
So I got the Borla dual, rear exit exhaust. Much less restrictive than the Borlas, as the standing start was noticably quicker. The Borla muffler was was too quiet, so I ordered a Flowmaster 40 Delta Flow and had the Midas guys just replace the Borla muffler with the Flowmaster. Beautiful, big V-8 sound now.
Now I have that wonderful artwork that is the Borla tips and piping, and the great V-8 sound of the Flowmaster mufflers. I never pull anything, so i don't know if torque is affected or not.
i do know that the TRD system made my acceleration feel very strained through first gear. With The Flowmaster, it flies through first and second with virtually none of the "resistance" i had with the TRD's.
i meant to say the Borlas seem much less restrictive than the TRD's I had on.
I got the Mod 40 Delta Flow with a 2.5" inlet, and dual 2.25" outlets, part number 9425432. May not apply to you as I had to get a dual outlet muffler to mate up to the dual Borla pipes. got mine from complete exhaust.com for $70. Good folks from central kentucky. I called and ordered at 16:30 one day and they shipped it the same day!
sounds incredible. Not too loud, very little resonance in the cab, but it does get attention!
Has anyone had good or bad luck with Flow Master's Dual Exhaust for the Tundra? I have heard nothing but bad things about the TRD Dual Exhaust. I just purchased the Flow Master Exhaust Kit, and I am apprehensive from installing it seeing how everyone says dual exhaust reduced their tourque.
I have a 2000 Tundra 4x4 access cab with 133,000 miles on it. I have had a series 50 flowmaster muffler with single inlet and two and half dual outlets on it for over 3 years and have not seen anything but improvements in my gas mileage and performance! I recently changed my factory exhaust manifolds for a set of ss autochrome stainless-steel headers. My factory exhaust manifolds were cracked inside and were leaking badly. I would have replaced the factory exhaust manifolds but, $250.00 per manifold was expensive when I purchased the set of stainless steel headers with the manifold and collector gaskets and bolts for $126.00 tax included! The reason I can make this claim is because I have [ compared] my tundra against 2 other tundras that were 2001 and 2002 models and wrer left behind by over 3 truck lengths! I also get 20 miles per gallon city driving using premium gas!
I had the Flowmaster 40 series installed about 2 weeks ago and am for the most part, very pleased with the overall sound and performance. One concern I do have though is the constant drone I hear while driving on the highway. It's a little louder than I prefer and I've thought about chaning to a 50 series but have heard it's too quiet. Any thoughts? Does anybody know if there's a way of quieting it down a little? I haven't talked with my local shop yet. I'll keep you posted if anyone is interested.
Last week I had Lou's Custom Exhaust throw in a Flowmaster 50 series dual out with 2 1/4'" piping. I haven't noticed any major differences other than the sweet V8 sound.
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Black 2000 SR5 AccessCab V8 4x4 / Debadged / Tow package / Factory Bedliner / Trans. rebuilt @ 72k / Stone Mountain headers / Flowmaster 50 series dual out the side / chrome tips / slotted and drilled rotors / air box mod / power outlet mod
I had the Flowmaster 40 series installed about 2 weeks ago and am for the most part, very pleased with the overall sound and performance. One concern I do have though is the constant drone I hear while driving on the highway. It's a little louder than I prefer and I've thought about chaning to a 50 series but have heard it's too quiet. Any thoughts? Does anybody know if there's a way of quieting it down a little? I haven't talked with my local shop yet. I'll keep you posted if anyone is interested.
Chris
You can try adding a resonator to the system or you can sound deaden your truck. The first suggestion will actually take the drone away the second suggestion will just make it less noticeable. The first is probably the easiest too. There are quite a few benifits that come with a sound deadened truck though, like a super silent ride and better sound from your stereo.
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"You play the hand you're dealt. I think the game's worthwhile." -C. S. Lewis
Just wondering, would the flowmaster dual exhaust kit for the Tundras work on the Sequoias?
more than likely not. i doubt the SUV is setup exactly like the truck underneath. the exhaust hangers could be in different spots, the pipes might hit things, etc. if you are going to put a catback on, definatly get one made for your SUV.
On the original topic, I have a lot of experience with different exhaust setups on Chevy trucks, and the best way to go for real power(lowend) is simply replacing the stock muffler and leaving the original piping in place. The 5.3 i have currently(not for long) has a 2.75 inch pipe stock, and once you go to a 3 you lose lowend. little changes make big differences when it comes to these motors.
I had the same problem that you are having. I had a problem with my exhaust manifolds leaking, Instead of replacing the stock exhaust manifolds , I ordered a set of stainless steel headers from ssautochrome for $1oo.oo. I figured that my Tundra would be much louder. To my surprise, my truck became quieter inside and the [roar] noise inside the cab went away! I don't understand what happened, but i'm glad that it did!
ssautochrome headers
Linear Mode
