.: Exhaust Modification Corner :.

[Veloc]

Seriously, I am confused now. I don't know what set up to do for my car. I remember you guys here saying for manual, less or no back pressure at all is good. But recently, I have a broken S-flow muffler. Surely the back pressure is less right? But the pickup and top speed seriously sucks. And my fuel consumption become very bad, besides the sound is super loud. How come?

My car is toyota AE111. 1.6L 4AFE manual. The stock piping is very small. 1.5" outer diameter and 1.3" inner diameter. So far the low end response is superb. I thought of changing to a set up that can improve low end and mid range. But I already afraid after my experience with my broken s flow muffler. If I change to 2" pipe, is it too big and will loose power? What is the ideal piping size?

 

[vr2turbo]

As far as I know whether manual or auto, back pressure is needed. Original piping are tuned for FC and normal use. To gain at higher normally will loose at lower, always have pros and cons.
Your piping cannot be so thick, 1.5" outer and 1.3" inner? that is 0.2" thickness....

 

[Veloc]

As far as I know whether manual or auto, back pressure is needed. Original piping are tuned for FC and normal use. To gain at higher normally will loose at lower, always have pros and cons.
Your piping cannot be so thick, 1.5" outer and 1.3" inner? that is 0.2" thickness....

Yes. It's about 1 mm per side. Got 2 side ma...
I also agree with the diameter size. The tradeoffs. But somehow I feel that 1.3" is like suffocating. Want to increase but not sure what diameter to use. I don't want to loose FC and low end. I just want improved low end and mid range.

 

[Dayline668]

Yes. It's about 1 mm per side. Got 2 side ma...
I also agree with the diameter size. The tradeoffs. But somehow I feel that 1.3" is like suffocating. Want to increase but not sure what diameter to use. I don't want to loose FC and low end. I just want improved low end and mid range.

Mine is auto same engine, using stock twin muffler set from 4age for many years now, FC wise i also lost since so many year of price hike, now rm40 can go 200km. The piping is around 2.3'' i think never measure but its big, FC after install surprisingly can go more, rev up faster, low end suffer abit, after so many year the inside muffler already kaput, i crank up the timing to near limit to get the FC above, without aircond can go 250km. Now dunwan to touch anything, consider satisfy with the power la.

I recommend u change the cat to a bullet n left everything stock for what u wan. This is what i try before.

 

[Veloc]

Mine is auto same engine, using stock twin muffler set from 4age for many years now, FC wise i also lost since so many year of price hike, now rm40 can go 200km. The piping is around 2.3'' i think never measure but its big, FC after install surprisingly can go more, rev up faster, low end suffer abit, after so many year the inside muffler already kaput, i crank up the timing to near limit to get the FC above, without aircond can go 250km. Now dunwan to touch anything, consider satisfy with the power la.

I recommend u change the cat to a bullet n left everything stock for what u wan. This is what i try before.

I believe you are saying you are using the stock silvertop twin muffler. I don't think that is 2.3" bro. It's around 1.8" only. By the way, RM40 for 200km is standard for auto 4AFE.

I'm trying to find the ideal piping size and setup for my car now. Aim is increased low and mid range but do not want loud noise. A little bit of noise is okay.

 

[nadziad]

hello sifu and friends...i want to ask about straight flow exhaust.currently my car using the s flow setup...if i change to straight flow.is it will make a loud sound than the s flow exhaust? i am using satria neo with 421 extractor + middle box + spiral middle box and the straight 3 inch muffler.

 

[vr2turbo]

hello sifu and friends...i want to ask about straight flow exhaust.currently my car using the s flow setup...if i change to straight flow.is it will make a loud sound than the s flow exhaust? i am using satria neo with 421 extractor + middle box + spiral middle box and the straight 3 inch muffler.

Should be louder....

---------- Post added at 03:46 PM ---------- 6 hour anti-bump limit - Previous post was at 03:45 PM ----------

Yes. It's about 1 mm per side. Got 2 side ma...
I also agree with the diameter size. The tradeoffs. But somehow I feel that 1.3" is like suffocating. Want to increase but not sure what diameter to use. I don't want to loose FC and low end. I just want improved low end and mid range.

Oh! 1mm then okay but you mention 1.5" and 1.3" and that is in inches.....o.1" is very thick woh!

 

[Veloc]

Should be louder....

---------- Post added at 03:46 PM ---------- 6 hour anti-bump limit - Previous post was at 03:45 PM ----------



Oh! 1mm then okay but you mention 1.5" and 1.3" and that is in inches.....o.1" is very thick woh!

Haha... Ya its around 1 mm. So I guess if the outer is 1.5", the inner should be 1.4" la is it? Didn't really measure the inner. I ask the shop guy he told me the outer. Then I ask about the inner He just told me agak agak 1.3". I was also surprised at first like "wow! 0.2" difference?". So I think the proper one should be 1.5" outer, 1.4" inner.

---------- Post added at 07:43 PM ---------- 6 hour anti-bump limit - Previous post was at 07:40 PM ----------

I noticed that immediately from my stock header, the piping is bigger. Around 1.8" I say. But after the midbox, it becomes 1.5". Is is recommended to change the whole thing to 1.8"?

 

[tingtk23]

Any sifu got knowledge about wrapping the extractor with thermal wrap??

 

[Dayline668]

I believe you are saying you are using the stock silvertop twin muffler. I don't think that is 2.3" bro. It's around 1.8" only. By the way, RM40 for 200km is standard for auto 4AFE.

The split muffler pipe already 2'' how can the bigger mid pipe be smaller, i will measure when i got chance get under the car.

---------- Post added at 10:46 PM ---------- 6 hour anti-bump limit - Previous post was at 10:42 PM ----------

hello sifu and friends...i want to ask about straight flow exhaust.currently my car using the s flow setup...if i change to straight flow.is it will make a loud sound than the s flow exhaust? i am using satria neo with 421 extractor + middle box + spiral middle box and the straight 3 inch muffler.

Straight flow confirm will be loud...

---------- Post added at 11:03 PM ---------- 6 hour anti-bump limit - Previous post was at 10:46 PM ----------

Haha... Ya its around 1 mm. So I guess if the outer is 1.5", the inner should be 1.4" la is it? Didn't really measure the inner. I ask the shop guy he told me the outer. Then I ask about the inner He just told me agak agak 1.3". I was also surprised at first like "wow! 0.2" difference?". So I think the proper one should be 1.5" outer, 1.4" inner.

---------- Post added at 07:43 PM ---------- 6 hour anti-bump limit - Previous post was at 07:40 PM ----------

I noticed that immediately from my stock header, the piping is bigger. Around 1.8" I say. But after the midbox, it becomes 1.5". Is is recommended to change the whole thing to 1.8"?

As i say, i try b4 stock just decat, can add little power to the stock engine bcos stock muffler is quiet free flowing. If u wan to change the piping size FC sure will up n some loss in low end. Just saying.

The levin twin muffler in the other hand, yes piping is bigger but its design for 1.6 also, even tho 4afe cannot rev as high as 4age, the muffler is design with a pressure valve, suite 4afe engine very well.

 

[vr2turbo]

Any sifu got knowledge about wrapping the extractor with thermal wrap??

Nowadays got Ceramic coating....

---------- Post added at 08:00 AM ---------- 6 hour anti-bump limit - Previous post was at 07:59 AM ----------

Haha... Ya its around 1 mm. So I guess if the outer is 1.5", the inner should be 1.4" la is it? Didn't really measure the inner. I ask the shop guy he told me the outer. Then I ask about the inner He just told me agak agak 1.3". I was also surprised at first like "wow! 0.2" difference?". So I think the proper one should be 1.5" outer, 1.4" inner.

---------- Post added at 07:43 PM ---------- 6 hour anti-bump limit - Previous post was at 07:40 PM ----------

I noticed that immediately from my stock header, the piping is bigger. Around 1.8" I say. But after the midbox, it becomes 1.5". Is is recommended to change the whole thing to 1.8"?

If not sure of piping size, don't attempt to change any thing yet until you find out more....

 

[tingtk23]

Nowadays got Ceramic coating....

---------- Post added at 08:00 AM ---------- 6 hour anti-bump limit - Previous post was at 07:59 AM ----------


Yeah, but ceramic coating is pricey.

 

[vr2turbo]

Yeah, but ceramic coating is pricey.

Have not done any wrapping before, but seen some on sale in mudah.com....

 

[neohadri]

Seriously, I am confused now. I don't know what set up to do for my car. I remember you guys here saying for manual, less or no back pressure at all is good. But recently, I have a broken S-flow muffler. Surely the back pressure is less right? But the pickup and top speed seriously sucks. And my fuel consumption become very bad, besides the sound is super loud. How come?

My car is toyota AE111. 1.6L 4AFE manual. The stock piping is very small. 1.5" outer diameter and 1.3" inner diameter. So far the low end response is superb. I thought of changing to a set up that can improve low end and mid range. But I already afraid after my experience with my broken s flow muffler. If I change to 2" pipe, is it too big and will loose power? What is the ideal piping size?

ekzos bocor actually increase back pressure, because area that leak have cold air, cold air means dense air, dense air means heavy air and it will block incoming air from exhaust by slowing it down thus creating very bad back pressure,

the same goes to bigger pipe except in FI engine, bigger pipe can actually create bad back pressure too because it make the air inside move out slower and becoming colder, denser & heavier which is no good

air is at maximum quantity at max engine torque i.e 4krpm, after that air quantity become lesser, with bigger than it should be pipe it can cause this air move slower if engine rpm is over 4k rpm

 

[vr2turbo]

But different engine have different max torque range, and how about latest engine with max torque from 1.8k to 4k...?