421 Vs 41

[carsial]

hi zthrians...
before i wud like to mod my exhaust..wud like some opinions from u guys..
1) its said tht 421 has more lows and 41 has more highs..is it true?
2) if i'll b using 41...will my FC b higher if i travel on busy roads wompared to 421?
thanks in advance!
hope for the reply...cheeers!

 

[sakuraguy]

1) its said tht 421 has more lows and 41 has more highs..is it true? - YES
2) if i'll b using 41...will my FC b higher if i travel on busy roads wompared to 421? - YES

:) .. 421 is common and just go for it .. dont end-up on illegal mods.

 

[Nieto]

but if use automatic transmission, dun use 4-1... u will lost a lot of power

 

[najibkl]

4-2-1 = Top speed
4-1 = Pick up

 

[rollakid]

4-1 bad bad FC (for me) T_T

 

[gohkokeng]

4-2-1 = Top speed
4-1 = Pick up

eh i tot terbalik

421 = pickup?
41 = top speed?

 

[xtorm]

hmm i use 4-1, really fast rpm, smooth high rev, an iswara feeling pull at 7k is fun...hha

4-2-1, more torque for the hills climb...

 

[fstr]

hmm i sue 4-1, really fast rpm, smooth high rev, an iswara feeling pull at 7k is fun...hha

4-2-1, more torque for the hills climb...

wahhh u SUE 4-1 haaa??? so keng haaa??? :p

 

[xtorm]

wahhh u SUE 4-1 haaa??? so keng haaa??? :p

diu lei lar.................hahahahaha

 

[Joeker]

4-1 is for hi rev.

As engine speed increases, the exhaust will need to go out faster. The collector at the 421 will reduce the flow. Therefore you will notice 4-1 primaries are usually very much longer than 4-2-1

4-2-1 is for low and medium revs. The collector acts as a siphon to expedite valve overlap scavenging and boost back pressure.

Howeverm if customizing is possible, you may increase the primaries' lenght of the primaries on the 421 tp get higher rev flow or reducing the primaries of the 41 vice versa, the point is to get something in between.

 

[Nieto]

may i ask, y sum extractor flexible? i heard flexible will be better~?? any different flexi and not flexi??

 

[Joeker]

All extractors are flexible/

It only depends wat they use.

For example Protons, they use a flexible hose which looks like a pineapple.

If not mistaken, Honda engine don use "pineappales" but they have a ball joint with spring retainers

These flexible joint allow for engine movement and vibration.

 

[Nieto]

hoho thx joeker~ ^^

 

[cooljas]

I can say, if the engine is fully modded eg, high cams, hi compression piston, port n polish...using a 4-1 on a fully modded engine it will gain power at every rpm..ppl say it will kill the torque n will improve in high end which i believe tis saying is 'bullshit'!
For those basic mods i will recommend 4-2-1 n it will be sufficient enough...if basic mod engine use a 4-1 then it only kills the torque

Juz my point of view, hope tis helps!!

 

[swap aka SWAP]

It also type of the 421 or 41 brand ma..me used svt 20v..eng standat also can used 4-1..cusco brand la..eng feel light..very easy to go to 6k rpm..ya..41 for high rev eng..

 

[alvin24]

4-1 is optimized for pick up and top speed oso lerz... it increases your high rpm torque.

4-2-1 is optimized for low-mid range torque... excellent for city driving.

Reason 4-1 has higher FC on city driving than a 4-2-1 is because the 4-2-1 has better mid range torque than a 4-1.... so if u use a 4-1... u'll end up tekan more to reach your desired speed.

 

[gohkokeng]

hahahaha can it be concluded simple like this:

421 = good for low RPM rev (perhaps below 4 or 5 k?)
41 = good for high RPM rev (perhaps above 4 ot 5k?)

 

[Nieto]

tat mean, nid to match with ecu eh~ and gearbox~

 

[gohkokeng]

haha i duno wo.....mine ANALOG stuff la......Carburetor Engine

somemore i not yet mod any exhaust system....only Apexi Power Intake (Open Port) soon will..... but for sure going for 421 cause manual

 

[Nieto]

ha ha... mine auto but using 4 in 1... bought custom made for racing 1 rm50 2nd hand he he... only high rpm got power, if city drive, wa... suffer~~