Lost power after exhaust set up

[marv3]

So far I have not heard from big to small. Most have them of equal size all the way. Only heard from one of my turbo friend with modded engine, from 2.5" all the way the near rear end go to 3". Even my turbo is 2.5" all the way. NA depending on CC can be from 2" to 2.2"......:rolleyes:

I think is pretty common now for turbos to go from big to small. I have seen a turbo car went from 3" at downpipe, to 2.75" middle piping and 2.5" muffler...... 3">2.75">2.5".....

But i myself use 2.5" all the way la....and the muffler is called a Loop Flow....Not S-Flow....Something the exhaust shop fella came up with.....

 

[Izso]

My understanding of physics is big to small will increase the velocity of the air but increased friction will increase pressure so you're effectively increase back pressure. No meh? Bournelli's law

 

[marv3]

My understanding of physics is big to small will increase the velocity of the air but increased friction will increase pressure so you're effectively increase back pressure. No meh? Bournelli's law

Tak tau wor. Dont understand also why he wants the back pressure in TC cars. More low to mid end? But anyways, its not the first TC car i heard of that does from big to small. As for me, just straight 2.5"....

 

[vr2turbo]

Maybe depends on what type of turbo also.....hahhaha

 

[^pomen_GTR^]

I think is pretty common now for turbos to go from big to small. I have seen a turbo car went from 3" at downpipe, to 2.75" middle piping and 2.5" muffler...... 3">2.75">2.5".....

But i myself use 2.5" all the way la....and the muffler is called a Loop Flow....Not S-Flow....Something the exhaust shop fella came up with.....

thats usually to cover up some lost midrange due to big turbo (turbo lag)...


but if it was me...i will prefer the best spool turbo option....(not a fan of big power and loosing torque at bottom end)

 

[marv3]

thats usually to cover up some lost midrange due to big turbo (turbo lag)...


but if it was me...i will prefer the best spool turbo option....(not a fan of big power and loosing torque at bottom end)

I see....

To me....I like smooth.....as linear as possible....easier to handle and drive....

 

[Shinjite]

I would say it's the extra mid box and the bigger piping size (I would say a 2" inner diameter will do) that you have changed to fix the original piping bend
You don't need more than one mid box to be honest, additional restriction.

For me, extractor -> midbox/bullet -> muffler, that's it :D

 

[Veloc]

I would say it's the extra mid box and the bigger piping size (I would say a 2" inner diameter will do) that you have changed to fix the original piping bend
You don't need more than one mid box to be honest, additional restriction.

For me, extractor -> midbox/bullet -> muffler, that's it :D

If I want more silence, but cannot use two midbox, how about using just one midbox but bigger? Will it be better or the same?

 

[KenDiriwan]

If I want more silence, but cannot use two midbox, how about using just one midbox but bigger? Will it be better or the same?

Guess what? This is current set i am using, more quiet than previous 2SET of different s-flow.

This is Greddy Power Extreme GS, sounded almost as HKS Silent Hi Power. Yet doesn't impact my fuel consumption and better power output.

 

[vr2turbo]

The one you polished, so still using this one?

 

[Izso]

If I want more silence, but cannot use two midbox, how about using just one midbox but bigger? Will it be better or the same?

Quietness doesn't work that way. If your resonator still is packed full of fibreglass and has strategically placed perforated holes, then it'll be quieter compared to 2 poorly designed ones (I'm not saying yours is, just saying in general).

Then your muffler also has to be packed with fiberglass for reduced noise levels. I remember back when I still had my Wira SE stock muffler, originally it was quiet. But over the years it got louder until the extent it was unbearbly loud. When I inspected the exhaust I was expecting to see a hole or 2 but nope. Instead when I knocked the muffler it was as hollow as an empty milo tin. It was pretty obvious! Compared to knocking on a new muffler, it was "thud" vs "konggg"

 

[KenDiriwan]

The one you polished, so still using this one?

Yep, my ideal sounding not too loud with reasonable consumption and satisfying performance. Am keeping it until it mampus.

 

[marv3]

Sound will depend on muffler size. As the name muffler suggest, it muffle the sounds. So, a rule of thumb, the bigger the muffler, the more silent it is. The diameter of the internal pipe will also change the loudness, but not by much if the whole muffler remains the same size as stock.

My muffler is the same size as the stock. But the internal is 2.5". So the sound isnt loud. In fact, ppl cant notice whether i change muffler or not. Just become abit more bassy.

 

[vr2turbo]

Quietness doesn't work that way. If your resonator still is packed full of fibreglass and has strategically placed perforated holes, then it'll be quieter compared to 2 poorly designed ones (I'm not saying yours is, just saying in general).

Then your muffler also has to be packed with fiberglass for reduced noise levels. I remember back when I still had my Wira SE stock muffler, originally it was quiet. But over the years it got louder until the extent it was unbearbly loud. When I inspected the exhaust I was expecting to see a hole or 2 but nope. Instead when I knocked the muffler it was as hollow as an empty milo tin. It was pretty obvious! Compared to knocking on a new muffler, it was "thud" vs "konggg"

Yup, my straight thru' setup up sound difference from new until now. Fiber glass in muffler gone already. Now the bass is more penetrating, not muffled......

 

[Veloc]

Guess what? This is current set i am using, more quiet than previous 2SET of different s-flow.

This is Greddy Power Extreme GS, sounded almost as HKS Silent Hi Power. Yet doesn't impact my fuel consumption and better power output.

I see that you have two midbox. One larger and one smaller. Mine is similar now. Just that they are not branded. Two medium sized midbox. I guess branded ones are really worlds apart huh? Silent, good fuel consumption and increase power all in one package? A bit too good to be true. But once and for all, I am going to try to get a branded 4-2-1 extractor hopefully some time mid year. Want to feel that mysterious all round good effects.