Tuning General Discussion [split]

[alexeiwoody]

Thank you GB, exactly right. But according to matt's logic we should all be rocking huge canons to increase our exhaust flow and turbo spool. Are you serious or is that a troll post ?

Matt you examples are irrelevant. Mmm waterfalls...mmmm mcdonalds...so delicious...oh no I got distracted by the pretty pictures.

Both these examples the inlet (niagra falls, my throat) is very large in comparison to the outlet (small waterfalls, mcdonalds straws respectively), so of course the outlet is the now the bottle neck. Why would you even bring these up?

Physics... thought it was simple. The rear muffler is congested with exhaust gas which slows exhaust gas velocity, so the muffler acts as a constipation point which reduces gas flow.

You're off topic mate. We're not talking about the muffler's internals, we're talking about the outlet. For the third time - as long as the outlet is same size or larger than inlet, there will be no gain from increasing the outlet further. (ok maybe 0.0000001kwatw - there, you win!)

So if the pipe work was 2" and I cut the back of the rear muffler off and fitted a straight through 5" pipe with the factory muffler baffles in place... by your reasoning and applied physics you wont make any gains other than more noise?

If you're talking about increasing the outlet of the muffler...Yes! And by your reasoning - we should all upgrade our mufflers before we do the dump pipe or the mid section, because the 2" tbe is not the bottle neck, according to you it's the muffler. Funny I don't see canons on your forester

I could do a long winded version of the physics involving waterfalls...water pressure...niagra falls..

This illustrates a 4"inch TBE with a 2" muffler. Not relevant here. We're talking about a 2" TBE with a 2"muffler. You can't flow more water out of a lake than is coming in, or it will just turn into a stream. There's not much point putting a 4" muffler on a 2" TBE.

Here is another metaphor:
Put one McDonalds Drinking Straw in your mouth and try to breathe in and out with your nose blocked. Now add a 2nd straw... Your throat is the same diameter but it becomes easier to breathe

My throat is not the same diameter as a Maccas straw. Example irrelevant.

Finally - a relevant example. If I asked you to blow as hard as you could through a 6" pipe or a 10" pipe, do you think you could blow more air out of the 10"?

Anwer: You can only blow as much air as is coming out of your throat. As long as the pipe in front of you is bigger than your throat, the flow won't be congested. The air flow would be the same.

Please tell me this was a big misunderstanding on your part, or prove me wrong.

[Kekotic]

Isn't Matts actual job based around gas flow......?

[alexeiwoody]

It's a high school level problem. Maybe 1st year thermofluid dynamics at best.

If matts job is with gas flow, then trying to prove the sti mufflers are more high flowing than std muffs is a joke.

[<GB>]

i did thermo dynamics and fluid dynamics years ago though...still use the books from time to time

[bass_straitener]

I have been to McDonalds many times and used their straws. I'm an expert too..

[alexeiwoody]

Their straws are the best for milkshakes....I like chocolate, what's your favourite bruce? You live 100m from maccas!!!