.: Exhaust Modification Corner :.

[flyturtle]

hey guys i wish to modify the exhaust system for my altis dual vvti, CVT . I bear in mind that i gonna have a s flow muffler and 4-2-1 extractor. however when i reach some shops they told me to have a 4-1 extractor instead. I m confuse here, need some good advice. And should i follow the manufacturer piping size?

 

[car.no.platenet]

hi there, i wonder what is the best exhaust option for a honda crv 2002??

 

[VectorX2]

hey guys i wish to modify the exhaust system for my altis dual vvti, CVT . I bear in mind that i gonna have a s flow muffler and 4-2-1 extractor. however when i reach some shops they told me to have a 4-1 extractor instead. I m confuse here, need some good advice. And should i follow the manufacturer piping size?

4-1 have a better power band at high end, and 4-2-1 have a better power band from low to mid end.

depends on where u want ure power to be.

i myself using a 4-2-1 because i hardly utilise high end power.

if ure speaking about cvt, i would recommend 4-2-1.

regarding piping size, u may enlarge slighly but not recomended, unless ure really sure it fits the right power band again. and again enlarging ure piping size too large could create havoc with ure Air Fuel ratio where ure original ECU kenot compensate. so as myself who is conservative i will keep piping as original as possible and use a 4-2-1 and a s-flow would be a good choice. try to save ure catalytic converter as well it might help ure car perform better as ure using CVT and also lend a hand in the environment. it may not be big, it helps a little.


not stoping to go for 4-1 and bigger pipping size, just my recomendation, someone with better expertise should point out sumting too if there is any mistakes in my opinion

 

[upontheriversky]

keep the stock pipe, get 4-2-1 and straight flow muffler having internal pipe size the same as ur current piping diameter or close enough, dont go more than 0.3" difference

auto/cvt can use straight flow, only need to make sure the muffler pipe matches ur current piping diameter, people got problem is due to i.e. 1.6" pipe goes to 2" straight muffler. Gas expansion causes turbulence and losses, losses is generally more than 2" going to 1.6" pipe. So better to constrict piping rather than expanding it :)

 

[shrizan]

arghh!! i dunno how to solve my exhaust system problem....

just now i change my catalyctic converter (in the middle) to street piping (stainless steel) coz the sound no bassy,macam tin kosong/trompet...then i try to change to swirl bullet (dalam berputar2)....but the problem is my sound masih macam tin kosong! no bassy sound n its like trompet! .

my car is caldina n/a 2.0

so now, my exhaust set up is 4X1 costume header/extractor (catalytic delete) , swirl bullet 2.5 , original silencer , S-flow muffler , original piping (2 inch)
@
4X1 --- original piping ---> swirl bullet 2.5 --> ORI silencer (bullet n silincer very close) ---original piping ---> S-flow FGK/Jasma.

my question is...mayB my S-flow muffler (FGK/Jasma) no more fiber inside ? or should i remove the original silencer ? can i use straight flow muffler (maintain piping curve ori to get back pressure ) ? .. thanx all experts!

 

[upontheriversky]

how big is the sflow?

 

[VectorX2]

4X1 --- original piping ---> swirl bullet 2.5 --> ORI silencer (bullet n silincer very close) ---original piping ---> S-flow FGK/Jasma.

why u have one silencer and then one bullet? the function is same isn't it?

just now i change my catalyctic converter (in the middle) to street piping (stainless steel) coz the sound no bassy,macam tin kosong/trompet

i dun tink so the catalytic converter is making ure exhaust sound high pitch

sounds more like lean fuel... could be also the muffler...

 

[shrizan]

my muffler inlet 3 inch outlet 4 inch...bro

---------- Post added at 11:43 AM ---------- 6 hour anti-bump limit - Previous post was at 11:37 AM ----------

mr vectorX2 .. first i use Silencer only...then the catalytic converter i change to stainless steel piping....but my fren/workshop exhaust said i need to use swirl bullet to reduce the pecah sound / auto transmission need swirl bullet to get back pressure..so i add the swirl bullet... but when i already change to swirl bullet , the isue still the same....sound like motorcross/pecah sound...no bassy sound...haizz..

 

[VectorX2]

try to go for sport triple flow muffler

 

[Andy0625]

my daily ride is a waja 4g18, i changed the exhaust to wegow 4-2-1, wegow 2" piping with 2 bullet(similar or same as r3 piping) and top cat sflow muffler. the idle sound is bassy but not loud. is there any way I could reduce the bassy sound and make the muffler sound loud when accelerate? just like those FGK muffler that is very silent when idle and loud when you accelerate hard?

also, i'm on auto transmission and seems my low end suffer abit, do you think it'll be good to change one of my bullet to a midbox to have more backpressure and at the same time reduce the exhaust note when idle?

 

[upontheriversky]

my muffler inlet 3 inch outlet 4 inch...bro

---------- Post added at 11:43 AM ---------- 6 hour anti-bump limit - Previous post was at 11:37 AM ----------

mr vectorX2 .. first i use Silencer only...then the catalytic converter i change to stainless steel piping....but my fren/workshop exhaust said i need to use swirl bullet to reduce the pecah sound / auto transmission need swirl bullet to get back pressure..so i add the swirl bullet... but when i already change to swirl bullet , the isue still the same....sound like motorcross/pecah sound...no bassy sound...haizz..

possible sources:
the pecah sound can come from the 3"-4" muffler, this type of muffler acts like a hailer/trumpet (small mic to big wide flared mouth to widen and amplify the sound) so any noise from engine will be amplified when it goes out the 4" mouth, and uve got 2" piping going to 3" and 4" at the end so it behaves much like a hailer. Bassy sound sflow usually has constant diameter, so it only gets noisy when exhaust flow rate is fast i.e. acceleration

u have changed to swirl bullet and the pecah noise still persists, it is a good indication that ur FGK muffler is the culprit.

my recommendation is swap the 3"-4" FGK to 2" big body (non-trumpet) straight flow muffler. I bet u will get improvement in both noise level and performance

My experience: i swapped my 2" oval straight flow to 1.6" big body straight flow and the noise level decreased a lot and gained top speed at the same time :)

---------- Post added at 04:55 PM ---------- 6 hour anti-bump limit - Previous post was at 04:48 PM ----------

my daily ride is a waja 4g18, i changed the exhaust to wegow 4-2-1, wegow 2" piping with 2 bullet(similar or same as r3 piping) and top cat sflow muffler. the idle sound is bassy but not loud. is there any way I could reduce the bassy sound and make the muffler sound loud when accelerate? just like those FGK muffler that is very silent when idle and loud when you accelerate hard?

also, i'm on auto transmission and seems my low end suffer abit, do you think it'll be good to change one of my bullet to a midbox to have more backpressure and at the same time reduce the exhaust note when idle?

if low end is not satisfying, try change the 2" piping after last bullet to 1.75", smaller pipe has higher exhaust velocity at low rpm so it helps.

 

[combax monster]

For lancer GT 2.0?

 

[TheSquee]

a b16a AUTO ( dont diss it please TY got it too often == ) using the old NON-VTEC engine's exhaust outer diameter is less than 1.8inch , currently car seems to not be making enough power even with 2 silencers and 1 s-flow muffler. have a feeling it is my exhaust piping problem since its so small as many VTEC specialist have mentioned VTEC exhaust systems are usually very free flowing , AUTO or MANUAL alike.
Many of them tell me to go for a 2.5inch outer diameter piping and throw 1 silencer away. And do a retune on my piggyback ECU

Any idea where i could go and do it for cheap ? :) Location/Shop Name and Telephone number is much appreciated. i Stay in PJ/KL

 

[Veloc]

a b16a AUTO ( dont diss it please TY got it too often == ) using the old NON-VTEC engine's exhaust outer diameter is less than 1.8inch , currently car seems to not be making enough power even with 2 silencers and 1 s-flow muffler. have a feeling it is my exhaust piping problem since its so small as many VTEC specialist have mentioned VTEC exhaust systems are usually very free flowing , AUTO or MANUAL alike.
Many of them tell me to go for a 2.5inch outer diameter piping and throw 1 silencer away. And do a retune on my piggyback ECU

Any idea where i could go and do it for cheap ? :) Location/Shop Name and Telephone number is much appreciated. i Stay in PJ/KL

Bro I think you meant 1 catalytic converter, 1 midbox silencer and 1 muffler. Well, get a high flow cat la. Don't just decat.

Maybe try this? /www.zerotohundred.com/newforums/engine-and-performance/244290-all-you-need-performance-part.html#post3126979>

 

[HaziqRais]

Im wondering, im using an auto that has removed the bullet and retained
only the cat and straight flow muffler. Its loud i dont mind but it sucks at low end.
Is it bcs i removed the bullet?

 

[upontheriversky]

Im wondering, im using an auto that has removed the bullet and retained
only the cat and straight flow muffler. Its loud i dont mind but it sucks at low end.
Is it bcs i removed the bullet?

most probably it. ur bullet formed an anti-reversion system at low exhaust speed. actually u would find that ur power overall will be reduced by removing just the bullet coz wave tuning is spoilt without it. wave tuning is the key to exhaust performance :)

 

[HaziqRais]

I see, so removing the bullet will make it lose power huh?
But the high end is great. Haha

 

[VectorX2]

I see, so removing the bullet will make it lose power huh?
But the high end is great. Haha

everything must be balance to achieve great power haha... shud consider how much time u need before u reach high rpm also hehe

 

[^pomen_GTR^]

for auto just decat and dun remove the bullet...other just maintain stock....


if want some sport sound a bit then just change straight flow back box that just slightly bigger....

 

[HaziqRais]

Thanks for the info guys. Btw, how much to custom made an extractor? For aveo.