Why standard exhaust system more save fuel?

dat is y swirl bullet were created specially for person like u...... coz u havin too big pipin for daily use..

d cheapest way to reduce noise + increase exhaust gas velocity at low end is reduce d piping size..

Can also look for the pressure activate valve muffler like the one in the FD2R. Low end works as normal muffler, and when pressure is high it opens and works like straight through muffler.....

like this?
http://www.horsepowerfreaks.com/partdetail...encers/ATS/7030

locally got sell such product?

omg. means i must choose between good workmanship and good quality?

guys, need professional opinion here..
my current exhaust setup is:
4-2-1 (wegow)
twist bullet right after the pipe joint (after flexipipe) =2.0" inlet/outlet
oval midbox after bullet =2.0" inlet/outlet
everco s-flow muffler = 2.0" inlet
1.6" piping

may i know what effect should i expect if i change to straight flow muffler?
or a long 4-1?
btw, car is 1.6l campro auto
current setup got nice pickup but top slightly suffers (quite heavy near 170kph onwards)
please advise, thanks

i think your pipe is too big...try 1.7inch pipe..

and consider using 1 mid bullet..but maintain current muffler

just a suggestion

i think the rule of thumb, for 1.6L engine, only go 2 inch or more with heavily modded engine or turbo

i disagree with it...piping size doesnt always relate to CC...its more on the amount of power u have and where in the rev ranger is that power at.

take for example 1.6...campros and CPS goes up to 2.0 and the gain is pretty decent... even CPS stock piping size is 2.0....go bigger and kaput...

but when it comes to the 1.6 MIVECs and VTECs...although the 2" pipes is pretty decent for those engines but they benefit more with 2.3" especially since most of the peak power is at the higher end of the rev range and the bigger pipe size really benefits the higher rev range.

my 2.0 VTEC is running 2.5" pipes.. and its good...so good.. 4-1, 2.5" pipe, 1 midbox, no muffler.

i also have an exhaust cut out valve.. so when the valve closed the exhaust is forced from a 2.5" pipe into a 2.3" pipe and s-flow muffler.....i lose 15hp about 1.2kg torque. tested this on the dyno just yesterday

so max n/a is 2.0"??? big big no.

lol... any cams wit 270+- duration or lower is OK..provided d lift is not to aggressive... works enginerrin / powerzone cam looks fine. jasma cam if u r on tight budget...

but d rough idle is vry adrenaline pumpin... huhu

https://www.youtube.com/watch?v=pb4e5jYZDdM&feature=related
agree... d pipe sizin is really depends on d engine characteristics n also d driver's handling d fuel pedal. there r act a bunch of software to calculate d piping size for certain rpm one's r aimin accordin to inlet valve, outlet, bore, stroke, cam duration n lift yadyadyadya..

but for rough guidance, 2.0" is still d magic number where alot tuner / guides use as threshold..lol
2 mufflin is enough at middle. 3 r too much...lol..  like i said, d cheapest way is change d piping size.. rm150+- settle..lol

what you need is to maintain the gas velocity with smooth and suitable size piping...not simply adding midbox and hoping that backpressure will imporve the pickup...which is wrong concept...

which picture? i saw the waja ones, he said piping is in original size that is 1.7inch...

ok la, i dont know about mivec / vtec...but for campro 1.6 with auto transmission need to use 1.6 / 1.7 piping, i tested already, anything bigger is ok, but you need to rev up all the time like a race car, just to overtake another car on highway..im not talking about top speed..with 1.6 inch or 1.7 inch piping you get some drivibility...

i suggest la you maintain your 2 bullet, and downsize your piping all the way to 1.7inch...or you go to exss work and get their opinion. 

so you want to have good high end power and low end power too? this one im still searching on how to do it..need expert tuner for that..its all about trial error.. but one thing for sure you need to revise your engine for that..tune for more horsepower and torque...rely on exhaust mod only wont do much, its about how efficient air in and out..

good workmanship im not sure..usually i go to normal exhaust shop, and worksmanship is ok ok only..as long as there is no leak then im ok..

hopefully anyone here can recommend good workshop, i want to know too..

Today managed to test my exhaust setup at Dato Sagor Track

I managed to clock 56.44 second per lap.     

Pair it up.. with this muffler..   

Not sure but he knows how to overhaul engines la...

Have any latest engine same as that for wira? 

Could be different brand issue. Different brand different make already.....

I use nismo.replica.hehe