.: Exhaust Modification Corner :.

[kweng84]

Straight Flow muffler improves low end torque but destroys high end power. However, it is not hard to balance up the power bands into an overall power gain from an exhaust system.

 

[donCityZ]

Straight Flow muffler improves low end torque but destroys high end power

kweng, are u sure? i was told otherwise by other people and by reading in the net. straight flow = cause to lose many backpressure (very low resistance for exhaust gas to exit)... if your car of lower cc (2000cc or below), and NA, it is advisable to use stock exhaust diameter. since low cc, there are not much gases to let out anyway if compare to turbo cars or higher cc cars. back pressure is very critical to have a good low end torque. at any time, the point is not to eliminate back pressure totally, its just to reduce a bit to optimal level. my opinion is that, using stock diameter with s-flow or semi flow probably the best setup for all 2000cc and below cars. if u just dunk in turbokits or the turbo halfcut, then the need to change exhaust diameter and bigger straight flow mufflers (or small muffler, but twin) comes in.

this exhaust concept can be applied almost similarly to induction too. (intake).
induction also need some sort of frontpressure to maintain low end torque. You can test by taking out the piping before the air filter box. sound more garang.. but low end torque diminishes. but try floor the pedal till 4-5k rpm.. u will feel the force greater than before.

 

[InitialD]

Anybody knows any S-flow muffler that sound nice? I mean something like Hotbits.

 

[donCityZ]

Hehe... u oso like Hotbits sound eh? Same like me... nice deep bassy sound..
i dont know.. perhaps S-flow from Hotbits???

 

[craziqbal]

hi guys, my ride was a stock 10 year old satria 1.3 carb bought from a lady driver, she took good care of the car...everything is stock and original.

recently, i changed the engine to a 4G15 EFI and i could achieve a top speed of 145kmh, which is not much bcoz, according to my mech, the exhaust system is not suitable and his recommendation is to change to 1.7" piping. what do you guys think?

also, i don't know whether this is related to the exhaust system, but, after high revving the engine, there is a strong smell of fuel, like the one u smell at the petrol station when filling up...is that unburnt fuel caused by the inefficiency of the exhaust system?

thank you in advance...really appreciate any help given...

 

[donCityZ]

ok this is my opinion. (dun flame me if im wrong)..

1.5 should at least reach 170km/h.. at worst.. (however i believe can go faster)..

ur car being light as it is (satria), should be able to reach >145km/h easily. i do not think there is a problem with the SIZE of your piping. My guess is probably there are some kind of leak on the exhaust flange or what not. OR.. the engine itself suffers some sort of problem... or perhaps ecu??

at high rev, smell of fuel is inevitable in normal engine.. at hi rev, ur ignition is not designed to able to fully burn the air fuel mixture.. however if smell is too much, probably there is a problem in the ignition too.. again these are all guesses... and im no expert.. just my opinion..

point aside, for example, the exhaust flame thrower works when u revv ur engine high enough until unburnt air+fuel escape to muffler.. then they put a spark plug at the end, and when spark is on, the excess air+fuel mixture burns.. voila.. flame thrower created!

 

[craziqbal]

oh, i forgot to mention, when i did 145kmh, there were 6 people in the car...heheh...probably can go faster...

 

[kob3bryant]

kweng
have u done a 6a12tt before,manual version.sorry for not getting the mugen as i am planning to get 6a12tt.wat is the recommended piping size?i think it would be better if i can have a setup to remain using my standard v6 muffler.dun wan to create high bit sound.

 

[ndselvam]

I user car 1.3 iswara -my petrol comsumption was high for 40 liter i barely get 300km - MY LMST car came with one F***** exhaust - changed it to 4-2-1 ext and 5 zigen mufler with cheap topcat bullet

NOw fulltank i get - 450km -500km town driving
Highway -I get about 650km

My change was worth it since i try so many petrol saver did not work
This was worth it did all with piping 1.6" for rm 450 in Kepong Exhaust shop

Power and performance i can say got slight increase abotu 5-6%

Only thing is - the exhaust noise is slightly loud - not very loud like bas mini - just nice

 

[kweng84]

Bro, 650km very geng lor..

 

[donCityZ]

oh, i forgot to mention, when i did 145kmh, there were 6 people in the car...heheh...probably can go faster...

err.. iqbal, 6 people or 1 people should not concern to top speed. if 6 people, u will reach top speed much slower thats all. (pickup less). it all about engine performance (ie. BHP).. i really weird wen u said 1.5 cant go higher than 145kmh..
i seriously suspect something wrong with ur piping... or engine...

 

[ekjozbuluh]

hi guys...
my question= is it true after we change our exhaust system da fuel consumption also increase ???
like my father car after he change to twin muffler why da pickup was a bit slow? is it bcos of auto transmission or something?

thanx in advance guys !!!

 

[kweng84]

hi guys...
my question= is it true after we change our exhaust system da fuel consumption also increase ???
like my father car after he change to twin muffler why da pickup was a bit slow? is it bcos of auto transmission or something?

thanx in advance guys !!!

Twin exhaust usually for draggers who wants high end power. If your dad's car is auto tranny, the setup must be able to keep enough backpressure ,else, the car exhaust will lose its rhythm to perform the best.

 

[bambino]

hi kweng u got any suggestions for an fc3s? wanna change my setup and am thinking of a crossover one. btw where are you located at?

 

[donCityZ]

once change exhaust for better flow, your engine breath more easily.....
once breath more easily, fc up... surely... if tuned properly, those fc up will accompanied by power up. if not, power more down, fc up... thats why it critical to do exhaust tuning carefully.. most kancil i see got huge piping and straight flow twin piping.. but running on stock engine... the response? bunyi aje kuat.. but no pickup... fc surely burning the owner pocket......... my 1.92 sen nia....

 

[nitrus]

quite kesian also kancil , if they wanna go for the big s-flow kinda shaped mufflers it won't really look good on their cars ... so i think the only way for them is the straight flow kind ... true ?

or the other not so loud kind ... but honestly , i would never use straight flow if i owned a kancil .. noisy but kereta tak gerak ... no offense kancil drivers , the turbo ones are cool tho ..

 

[calvin27]

blur..

Can any once pls give me some advise..im driving Myvi 1.3 manual with 1.5inc rim only.done my exhaust system. direct flow is a bit noisy.straight no sound..Pls give me some suggestion of what flow should i use. If im not mistaken ,straight flow less power go up hill then s flow izzit?
straight is only for pick up? how bout after long run?

 

[nitrus]

calvin27 , after long run u'll be pounding ur brains lor bout the sound resonating thruout the whole cabin the whole time u're driving ... lolzzz...

 

[bambino]

so can anyone advise me regarding my previous posting? thanks

 

[joe_mivec]

Guest, mind tell me, the good exhaust setup for my Mivec1.6? coz this engine hv high rev behavior, so that the power and torque come late at high rpm only...so how the good setup if i wanna boost little bit low/mid end torque without sacrifiying the good high end torque? thanks...