.: Exhaust Modification Corner :.

[kent20]

GTi isn't it better with 2.2" piping?
Same with MIVEC? MIVEC engines best is around 2.2"/2.3"

bro if u did port and polish or any modification on your gti 2.2" is good
same engine code but different functional,Gti dont have "MIVEC"
as i mantion what dont have mivec????sure got ppl gorek kepala

Mivec(Mitsubishi Innovative Valve-timing-and-lift Electronic Control) is Similia like:
VTEC(which stands for Variable Valve Timing and Lift Electronic Control),original 4G93P only 1.8 twincam they dont have this function so 2.2" for original 4G93P is too over

 

[soggie]

My car's a Satria GTi with Evo 2 engine. Currently piping is 2.5" to nanas, then 3" all the way down, no mid box or bullet, to a HKS Hi-Power Exhaust without the removable silencer.

I wanna make it more silent, without sacrificing too much on power. There are 2 ways I'm gonna do it:

1) Replace HKS Hi-Power with Tanabe Medallion S-Flow

2) Add a middle bullet, don't change the muffler

Which one would be less noisy?

 

[Massive_InfusioN]

Well, you got high cams,open pod k&n, it is a very wise choice u have there in modding exhaust system.

Your ride has a good head power but no 'tail'. Stock muffler is very restrictive having small inlet piping size, big blocks which creates back pressure which you dont need it. If you want good high end power with low end/middle end increased, get a good 4-1 extractor, change 2" full piping, take off CATCON, take off the twinpipe sflow muffler and replace it with a nice good 2" straight flow muffler which means single exhaust system. (Juz my 2 cents, based on the experience of modding few GTI's exhaust).

Yes, i can feel the backpressure Blocking the exhaust flow. Sort of a restricted feel. Eventhough the intake sound from the open pod is quite loud!. The best thing is, its silent !

Thats why i came out with the idea to modify the exhaust system. Just an idea, but need your feedback from it.

Kweng, a 4-1 extractor help to unrestrict the flow, i bet it shall boost-up ,But will i lost low end power? What is the feel would be if i were to use a 4-2-1 compared to a 4-1 extractor?

Nowdays is hard to find an aftermarket muffler simmilar style as Gti's (Twin tailpipe).....

 

[kent20]

My car's a Satria GTi with Evo 2 engine. Currently piping is 2.5" to nanas, then 3" all the way down, no mid box or bullet, to a HKS Hi-Power Exhaust without the removable silencer.

I wanna make it more silent, without sacrificing too much on power. There are 2 ways I'm gonna do it:

1) Replace HKS Hi-Power with Tanabe Medallion S-Flow

2) Add a middle bullet, don't change the muffler

Which one would be less noisy?

2) Add a middle bullet, don't change the muffler(reduce 30% noise,power still maintain)

 

[kweng84]

My car's a Satria GTi with Evo 2 engine. Currently piping is 2.5" to nanas, then 3" all the way down, no mid box or bullet, to a HKS Hi-Power Exhaust without the removable silencer.

I wanna make it more silent, without sacrificing too much on power. There are 2 ways I'm gonna do it:

1) Replace HKS Hi-Power with Tanabe Medallion S-Flow

2) Add a middle bullet, don't change the muffler

Which one would be less noisy?

Sound wise,I think the best in reducing the noise would be getting Tanabe Medallion S-flow. Tanabe S-flow got very sufficient bass there and won't too loud. I am one of Tanabe lover too. How much u getting for that sflow?? from kedai potong?? if yes, gotta becareful ya...

If you want to maintain power and reduce noise also, i agree with kent..bullet is the choice..

Yes, i can feel the backpressure Blocking the exhaust flow. Sort of a restricted feel. Eventhough the intake sound from the open pod is quite loud!. The best thing is, its silent !

Thats why i came out with the idea to modify the exhaust system. Just an idea, but need your feedback from it.

Kweng, a 4-1 extractor help to unrestrict the flow, i bet it shall boost-up ,But will i lost low end power? What is the feel would be if i were to use a 4-2-1 compared to a 4-1 extractor?

Nowdays is hard to find an aftermarket muffler simmilar style as Gti's (Twin tailpipe).....

Actually extractors (421 or 41) unrestrict the flow differently. Firstly 4-2-1, just imagine when we accelerate from idle, the gas flows from 4 pipes to 2 pipes then to 1 pipe. Common sense will tell you that 4 pipes to 2 pipes is better flow than having 4 pipes to 1 pipe. So, 421 will give better low end torque than 4-1. get it? just my 2 cents..if im mistaken, anyone pls correct me, thanks !

 

[kent20]

if any one want to use 4-1 your original already 4-1,for what u change it?

 

[kent20]

Tanabe Medallion S-Flow
kedai potong selling RM200 only ma
but shake it see got burning cotton come out or not 1st
if need to refiber better dont take

 

[divenom]

is dis kok weng?

 

[kweng84]

if any one want to use 4-1 your original already 4-1,for what u change it?

Bro, i think sure got ppl finding bigger piping size for their 4-1 extractors rite?

 

[donCityZ]

i think for stock 4-1, the 4 piping is too short.

for racing purposes, the performance 4-1, the 4 piping is longer until below engine and only join to become 1 pipe. it is for hi rpm performance.

correct me if im wrong.

 

[kweng84]

Yeahlor..i see a lot of tuned length 4-1 also got different style of making the extractor 4-1 . Just like 4-2-1 designs..so many of them..

 

[nitrus]

weng, so why ppl selling 4-2-1 extractors more than tuned lenght 4-1 extractors ?

coz of more daily drivers?

 

[kent20]

i think i miss out some word,4-1 for wira/satria even gti all are not recommeded..
1.original already 4-1.

usualy why ppl change to 4-1,it because of those ppl like using
VVT-I,Vtec,Mivec,all thing hight rev engine or for track car purpose,because they want to keep the hight rev,as we know most of the track car always have to stay on 5k-8k rpm...

so for street car,like what we playing 4-2-1 is the most suitable
because:4-2-1 improved the pick up and mid,also improved the torque,during street usage 4-2-1 is always lightest then 4-1

another issue,original extractor normaly is made by lousy besi buruk,
1.heavy
2.inlet not smooth enought in the same time the airflow is not smooth enought
so maybe they have to change to aftermarket 4-1....

but untill now i also can't find out what is the pro for 4-1 on street using...
if track car maybe it because of what i mantion keep hight rpm...
the rest i really dunno why 4-1...any expert to answer pls

 

[kent20]

addon if keep the piping original way enhust the size of original to 10%-15% you wont lose the back presure,only over size/directly pipe(after 421 directly 1 straight pipe fly to end muffler) this one will lost back presure,so what is the con if lost backpresure?
1.you will heavyest lost the mid torque low end torque

the pro

it will inscress the horse power on hight rpm

 

[kweng84]

weng, so why ppl selling 4-2-1 extractors more than tuned lenght 4-1 extractors ?

coz of more daily drivers?

Briefly, 4-2-1 provides better power at low and middle band, thus, for city-drivers , who accelerate less than 5krpm before shifting next gear, it will be better fuel efficiency or better fuel consumption as power increased at that power range.

 

[jaxeus]

Kweng,

I have changed my mid bullet with the spiral type one and muffler with 5' mozza. I've
found that my drive has lost top speed, may i know whether i can add in a mid box or
another bullet (normal one) to recover the lost. thks

 

[20vturbo]

kweng, im using 2.2 piping with no flexible pipe(nanas) s-flow to one bullet and to muffler..i notice piping got like rattling sound.for the moment the sound is silent.coz using jasma tanabe.i just want more power but dun want an increase in sound.what do u think? remove the bullet and put nanas? will it make more sound?

 

[nitrus]

i thought the "nanas/flexipipe" is there so the whole piping can move freely a little or something? u took it out ? maybe thats why got rattling sound ?

 

[drew1.0beta]

hmm.. wats the recommended exhaust setup for 4efte auto?

 

[soggie]

4efte? Stay original. Remove cat, and get a better flowing s-flow exhaust. Then keep it that way.