Best 3rd GEN Exhaust Systems

This is a great thread. It has singlehandedly informed me of several things. Don't worry about exhaust, not worth changing until you have to. Second, tacoma owners are kinda sensitive. But that I get. Also, opinions are like a-holes (but that was just a reminder). For the record, thank you all for covering every question out there.

 

LOL. Can't argue with the truth!

 

LOL, welcome to TacomaWorld!

 

Your need to have verifiable evidence from a dyno is understandable. @Torspd has compiled a long list of dynos from various TW members. The following link will show that the URD y-pipe that removes the rear cats has a substantial effect, at least at the higher RPM ranges. If you go down around 5 dynos from the top of this link you will find Lucario Runners dynos before and after adding the URD y-pipe. He has the 4.0 engine but the results should be similar for our 3.5 engines. Hope this helps.

https://www.tacomaworld.com/threads/n-a-power-gains-dynos-w-mods.229882/

 

Doesn’t that 4 Runner have headers? That is in no way comparable to our engines at all. A 4.0 with headers will not react to a cat back the same as a 3.5 with stock exhaust manifolds.

 

so far......stock

 

My butt Dyno says my mbrp turndown added at least 60hp cause it sounds like a V8 when I get into it. It also added the collective torque of everyone's snapping necks when I go by, which unfortunately cannot be measured on a dyno- the technology just isn't there yet.

 

Can anyone share info on the Magnaflow as far as interior noise & exterior. I'm not trying to get my Taco to sound like a V8 or anything, but I'd like a nice deeper, throater sound. From the You Tube sound bites I've heard I like the exterior sound of the Magnaflow. I put a Flowmaster in my 2003, V8 4Runner and it sounded great! but the interior sound was too loud. Just trying to avoid doing that again.

I priced the TRD Pro Exhaust & Intake at my local Toyota Dealer and they wanted $809 for the Pro Exhaust installed and $475 for the Intake (in the box). That's a little more than I wanted to spend at the moment. I can get a Flowmaster or Magnaflow for a few hundred dollars.

Thoughts or ideas?

 

You missed his point.

 

I have a MBRP 3" (*modified) cat back. *It was a pre-axle dump when I got it, nice sound, I really do not think there is any measurable increase in power. I have since added more pipe (2.5" from the muffler to a 3" tip) with a behind the tire exit to diminish highway drone, major improvement in amount of drone and in cab sound level though is did raise the frequency, about 2.5 to 3 steps.

I can say, IMHO without removing at least 1 set of cats you are not likely to see any real gains. The sound will be better depending on personal perspective and you may get a good increase in smiles per gallon. If you want improved performance, you need to change the tune, re-gear, add turbos, etc. Changing intake or cat back exhaust will change sound but the ECU will adjust to compensate to the changes flow negating any very minor short term gain.

My MPG's from stock exhaust, to axle dump, to current set-up are really unchanged. They did drop initially, mostly due to my ear telling my foot to go deeper into the pedal. Once the initial grin induced heavier than normal foot wore off MPG returned to previous averages. The adding of pipe also made changes only in appearance and the sound pitch, which still is better than stock IMHO. Tank mileage is still sitting right at the MPG of total ownership. I used Fuelly to calculate and verify the cluster reading and both are on par.

 

Quite possibly. Explain to me what his point was

 

My point was only that removing the rear cats will produce a noticeable gain in HP. I did not mention the headers or the cat back exhaust. The exhaust gases have to get from point A to point B ie from the engine to the exhaust tip. I understand that the headers are built into the cylinder heads on the 3.5 while they are on the outside of the heads on the 4.0 but the gases still have to get from point A to point B. The cats are the largest obstructions to that flow. If you were ever to frequent the performance section of TW you would find that @Torspd probably knows more about the performance of these trucks than anyone else on TW. He has raced his truck and owns 3 separate engines that he has built up. He has done his own welding and fabrication work and was tuning his engines long before OV tune showed up. I copied the dyno instead of the link this time.


EDIT**** Lucario Runner's after the addition of the URD Y-Pipe. Take special notice of the gains at the end of the curve. HUGE Increase in HP and TQ.

 

ok, I did get the point correctly.
I don't know anything about @Torspd but I see he is following. Awesome. So exactly how does the map of the 4runner shown equate to a stock 3rd gen? I see a TUNED 4.0 motor with aftermarket intake, aftermarket ECU, headers and a bunch of other mods. How would gains in that motor with a cat back quantify equally to a STOCK 3.5 with no other mods? The cats are the biggest restriction so getting rid of them will give a substantial boost in HP? By that logic, I could also unbolt my exhaust from the cats back and enjoy a massive gain is horsepower? I think anyone worth their salt knows that isn't true. The reason I mentioned the headers was because if you changed the headers to a stock pair on that same 4.0(no tuning changes allowed) and changed nothing else you'd see a substantial decrease in HP. Now put the stock cat back on bolted to that stock header and you will see barely any additional HP loss because the header is now the restriction on the breathing of that tuned 4.0. Everything after that header doesn't matter too much anymore. With that tuned 4.0, everything was built to address flow and the restrictive part was the cat, remove that and the HP numbers go up substantially. On our stock 3.5s that are tuned to run in a certain configuration, changing the cat back in theory will allow it to breath better but without the corresponding efficiency of better scavenging from the cylinders to the cats and an ECU that will allow for a more efficient running of the motor you won't see a measurable improvement in HP.
Mind you, all this useless arguing is really a moot point anyway cause all those gains are only realized on the TUNED motor from 4,750 on up. Looks like about 6HP gain at 5,000. I can count how often my revs get that high on a daily basis on one hand. Also looks like TQ maxed out at 3,800 RPM with a LOSS of max TQ. Yup...a LOSS of TQ in your daily driving range. Realistically, how often is your daily driven pickup buzzing over 5,000RPM? Less than 1% would be a real answer. I'd take +3 Ft-lbs of torque at 3,800RPM over 6 HP at 5,000 any day of the week but I digress.
I still stand by the fact that on a stock 3.5 you will see very little measurable improvement by adding a cat back, if any.

 

I don't know why you keep bringing up the cat back since I specifically stated in both of my posts that I was referring to the removal of the cats only. I agree that adding a cat back exhaust will add very little improvement. I also agree that removing the cats will reduce the back pressure which will lower the exhaust velocity and which will reduce the low end torque. I never said anything about torque in either post nor did I say that the gains would be equal to the 4.0. His HP went from 213 HP to 242 HP which is a 29 HP gain. His torque at the upper end went from 193 to 219 LbFt which is a gain of 26 LbFt. Without similar complementary mods our gains will be less but still much more than the cat back you keep talking about. You are also correct that we normally don't spend much time in the upper RPM range but I want to know that if I am passing someone on a 2 lane road that I will have every last HP available.

 

No, you didn't say equal, you said similar. "HUGE increase in HP and TQ"
I shouldn't say cat back, I mean ANY exhaust mod. Cat back, remove cats, gut the cats, take off the whole system...none of it matters. Take out just the cats if you like, still very little difference was my point. I believe they are called test pipes in the rice world. They make no discernible difference on untuned N/A motors.
Look at the MAX TQ number on that graph, stock is higher than modded. It's not rocket science. BTW if you're passing someone on a 2 lane, it's TQ that gets you passing not HP. This is a truck not a performance car. Funny thing about that dyno sheet is that it doesn't even start tracking the TQ (of what I assume is the motor with stock cats) till it was already at peak torque and falling at 3,700rpm which could quite possibly mean that the torque was even higher at 3,500 which is probably the RPM where you would downshift to to pass someone. HP was higher than no cats at that point too.
In any event, like I said, comparing the 2 motors is like comparing an eggplant to a penis, same basic thing but not relateable.

 

Sir, I prefer something in the butternut squash category if we have to go with a fruit or vegetable.

 

My wife shared with me her dyno numbers from the butternutt squash and she assured me that my eggplant did not show similar gains.

 

I don't know why you feel the need to be so hostile. I tried to agree with you on some points even though they were totally irrelevant to the one point that I was making. Unless you can come up with some dynos of your own proving your points you are just wasting our time. I understand it can be difficult to believe your lying eyes especially when they disagree with your deeply held opinions and biases. I never would have answered your first reply if it were not for the post that @Torspd put up. You seem to be young and immature with your eggplant remark so I will gladly let you have the satisfaction of having the last word because I am off of this thread.

 

The only thing you brought to this thread was just enough unrelated BS to keep the young and impressionable's exhaust dreams alive. The shit you threw into the mix here has nothing to do with the OP's question. But I digress, if he's already 'feeling' the benefits of a CAI, throwing more cash at exhaust will probably really put him in the fast lane..

 

Stock is best.