Having regrets w MBRP 3” exhaust/ looking to get the TRD exhaust

Put the stock back on.

 

Honest question:

Can someone explain to me, in short form, how a less restrictive exhaust causes loss of power (at low RPMs)?

 

Oh it's a 3 inch exhaust?! Holy crap that is SUPER overkill for your engine power output. No wonder there was a loss of power. Your exhaust is no longer optimized to run within it's powerband because the exhaust is TOO free flowing. Bigger is not always better. Of course the guys at MBRP do not understand so that makes me question their intelligence as an exhaust production company in the first place... But I digress there, so anyways..

Let me give you an example of what I'm talking about so you can see what I am saying here.

A 2.5" exhaust is good up to about 450 horsepower before it becomes a bottleneck. I run something around 370-380 HP out of my Tacoma and 2.5" piping is within it's proper power range and I am supercharged, you guys are not and make notably less power as a whole. If I step up to 3" not only does that take me out of my proper exhaust piping power range but it becomes too free flowing thereby it hurts any potential gains I can possibly hope to make with it.

It's almost like attempting to drink water or juice out of a cup with a small straw. You get a good amount of it with each suck... If you change the size of the straw to one that is unnecessarily massive than you will have more of an issue getting that same amount of water or juice out that you were with the smaller one because you have to attempt to suck harder since it is too wide open.

Does that make sense? I hope it does.

 

yeah that makes sense, I read up a lot of other info in other threads here on TW about a bigger diameter exhaust will indeed have power loss lol

 

I wish i would’ve thought along these lines before. I know someone mentioned there is no power loss with bigger diameter pipe but the eye test says otherwise... can you send a link to the Borla?

 

I’m actually happy with the sound, just more concerned about the droning at highway speeds and the noticeable power loss...

 

No problem man, and thanks. Yea that whole life thing.... kind of important lol.

 

That’s awesome! I’m looking into getting the OVTune as well as i keep heading great things! Wondering if i should hold off on getting rid of the MBRP until after the tune to see if there’s a noticeable difference. Also, apologize for the illiteracy, but what do i look for when looking for a resonator?

 

I like the idea of the TRD exhaust.. but at 699... it’s a tough sell... specially when I’m thinking of getting the OVTune... i feel as though that would be a better investment for now...

 

People say the lost of back pressure causes the lost of low end power, but that is incorrect.
It is lost of exhaust gas velocity which assist with scavenging that causes the lost of low end power.

The tigher piping actually helps with scavenging in low RPMs, as the gasses pass, they create a vacuum help extract exhaust from the other cylinders.

Larger piping allows for more flow which helps a lot at higher RPMs, but at low RPMs the free flow does not cause the gasses to jet out.

Like a small diameter water hose vs a thick water hose, at low water pressure (engine RPM) the water would be flowing out at a higher rate compare to a larger diameter hose.

 

Same diameter as stock at 2.5” or bigger? Or smaller?

 

So you’re planning on reinstalling it even with the low end power loss?

 

I’ve heard that point made before, about loss on one end but better at high end... however, most of my driving is city, with some highway on weekends, so it would behoove me to focus on getting that low end back... which is some’ i should’ve thought of before i spent 440 on the exhaust lol... hindsight is a MF!

 

Dude! The moment you mentioned pipe sizing in relation to output it clicked... now i feel so fn dumb. I’m a gas fitter and do appliance install as well... and that same process happens when sizing vents for boilers water heaters based on BTU. Too big of a vent and the appliance doesn’t create enough product to draft and heat up the chimney... DONT mean to flex on y’all, but I’m just pissed at myself for not thinking along those lines before.

 

You can get a resonator welded or clamped right before or after the muffler.
I opted for resonator tips, DCSport 2.5"

I now have URD YPipe, which brings out more of the V6's rasp, so now I put more resonators, or an insert or a helmholtz resonator to kill off that rasp.

 

Thanks for the info, also thanks for your previous response on low end power loss... looks like i still got a lot to learn in this Dept, i shoulda came here first before i dumped 400+ on this exhaust

 

Go back to stock.

If you are itching again for noise, drill a hole in your exhaust!

 

Lol, it’s looking like the most likely scenario. Not the hole thing but going back to stock thing haha.

 

yeah I'm planning on reinstalling the mbrp exhaust mainly to see how much the sound deadening material will help reduce cab noise drone. after that, I'll probably drive the truck a few more times with the mbrp exhaust(enjoy the nice aggresive tone before i sell it) then I'll reinstall my current exhaust

 

Icepick mod.

My old school GTO forum dudes used to run washers between their mufflers and their pipes to get slightly louder exhaust over stock. The mufflers were, however, literally dump off style. Right at the end of the exhaust piping. So it was easy to do such ricer mods. Us on the other hand have properly designed exhausts.