question regarding exhaust mod,,

[Coltrain]

BV5015,
VTEC controller ?!!
if his car is i-DSI y need to buy VTEC controller ?
not buy SAFC meh ?!!
correct me is i'm wrong...

 

[sonictheory]

sonic,get v-tec controller lor...
and controll the air flow..
than u can cincai modd ur filter,extractor,bullet,muffler...

but i tough if using 7 speed,rev liao will auto jump gear de? my fren idsl was like that

wat mean after add vtec controller can cincai mod filter extractor bullet and muffler? tak faham

well 7 speed mode got 2 types...1 is semi-auto..u turn on 7speed mode, u accelerate, when in certain RPM it shift gear automatically for you... another is after u activate ur 7speed mode, u shift down 1 gear, M will light on, means manual..this 1 u can shift ur gear u like...can rev kao 6 RPM only change gear also no problem...but in certain RPM u still not change gear, it will shift automatically for you again to avoid spoil the engine...

 

[BV5015]

Coltrain,
i refering to Sonics rids,if not mistaken his ride is V-tec
But my fren's is IDSL,different car.

Sonic,
As known, V-tec controller is gd to adjust the opening time and air flow for v-tec enjin. so,after all those modd relating to air/oil support. a v-tec controll ler will helps the performance.
for your case, notice that you are interested for open pod/extractor,mid bullet,tail muffler..to well perform these stuff,some ecu tunning is required.
correct me if im wrong,v-tec sifu here.

for 7-speed mode. yes,same case here. i think before red-zone than the gear will auto shirt up....that's a waste for this system...haha.
imagine,with 7 speed....all shift gear when red zone....listen the enjin screaming...shiok mar~!

 

[Coltrain]

BV5015,
well,his car is VTEC ?not sure wo.....
well,rev until red zone ?care blow the engine loh

 

[BV5015]

yalor.built in rev speed cut to protect it....wasted a v-tec powered enjin...haha

 

[Coltrain]

hahah....put a rsm into it....then can rev till engine blow...hahaha

 

[BV5015]

self control self control....:P

 

[theorekz]

i went to an exhaust shop today... to my suprise, the boss tell me that those bullet thing is not good at all for a modified engine or non-modified..... because it creates the spiral at the middle which restrict the flow of exhaust gas... if want to tone down the muffler, install those "fat-box" as the mid-box.. dont install bullet... N this bullet, in fact is only creating a "feeling" that makes u "think" it is more powerful after installing it...

any comment??

 

[kweng84]

i went to an exhaust shop today... to my suprise, the boss tell me that those bullet thing is not good at all for a modified engine or non-modified..... because it creates the spiral at the middle which restrict the flow of exhaust gas... if want to tone down the muffler, install those "fat-box" as the mid-box.. dont install bullet... N this bullet, in fact is only creating a "feeling" that makes u "think" it is more powerful after installing it...

any comment??

bro, i dont get you with this sentence "because it creates the spiral at the middle which restrict the flow of exhaust gas". Mind to explain a bit?

I know there is something better than bullet which looks like a muffler box but with the tip...it reduces more sound than a bullet... tested with many cars..i sell those, i know...but, u mean spiral issit the design in the bullet like Zenden style or those really spiral that we actually cant see through the bullet inlet hole as the spiral blocks everything...pls explain ..thanks..i need to learn also ;)

 

[theorekz]

kweng bro.. sorry for the brief explaination... hehe.. very paiseh... u see ar... the bullet's spiral effect is just like the 1 inside a washing machine.. when it turns, it will create a point in the middle right?? so in the bullet, this causes the exhaust air to focus in the middle.. thus restricting the flow..

the spiral effect can be seen very obvious through the bullet... u can see that inside it, there's different orientation of the metal plate inside... if using those fat mid box, it is something like a s-flow muffler.. cant see through the other side directly... if bullet, can...

cheeers//..

 

[kweng84]

theorekz: I get what u mean now ;) Okay, as u said there will be a creation of middle point in the bullet when exhaust is flowing through. There is actually where we can gain low end power. See, my theory will be when exhaust flows into the inlet holes to the cotton/fibre, it will create a circulation that causes the exhaust to focus in the middle(thats what u said). Correct with that! But the thing is that, lets visualise..when the bullet exhaust is focusing into a middle point,thus, we can say that the exhaust is flowing in a smaller path which actually will increase the speed of the exhaust to flow through and there is where we get better performance effect. Similarly, we can fix a smaller inlet piping in between of the standard downpipes to make low end power.But , no way!! it will be bloody noisy...thats why we need the cotton to reduce the noise.

We use bullet is to silence the exhaust into a better bassy sound besides giving some pick up power for our car. We rarely use midbox because it reduces the sound into some 'hollow' sound(if any of u get what i mean). So, thats what i can say for now;) if anything i have mistaken, pls correct me. This is the purpose of this thread i supposed ....

 

[Coltrain]

using bullet will get nicer sound ?
well,if not i'm now using 1 S-flow type mid box,then add one bullet. is it ok ?

 

[kweng84]

yeah, u can feel the difference if u r using stock muffler where the bullet sound comes under ur seat..low bass. S-flow type midbox for automatic cars i supposed. Adding one bullet will give a little bit performance effect. If u are auto, use two bullets i suggest. u auto or manual??

 

[Coltrain]

Kweng84,
i'm driving auto car.....
i'm currently using one mid box,feel like my car need abit more back pressure,so planning to add one more.So thinking to add bullet or a small mid box.....

 

[markii]

kweng84,
how come 2 bullets? will the power be significantly different with 2 bullets than 1? if use 2 bullets, what range will be gained the most? i currently have 1 bullet and interested in improving my pickup speed.

 

[kweng84]

coltrain: can u explain a bit more on the back pressure u r referring on? for automatic cars, if u need pick up but also to maintain ur middle end power..u shouldnt change for bigger pipings...maintain the stock size...sflow midbox can help on ur pick up but it should depend on the quality of midbox u using...if those branded sflow midbox, i say go ahead but if it is those sflow midbox which cheaper than rm200, i suggest u take normal type midbox with better fibre which cost a bit cheaper than the sflow ones.Also, you can use bullet to replace the midbox. People take midbox because it reduces more noise than bullet.For me, i want some sport sound of course;)

markii: i suggest two bullets if those type bullets are those which i have known. There are bullets that are specially made for automatic cars. It has own unique pressure for certain car models and for this type, you dont need two bullets. You might need to seek for those(description: the whole bullet looks curvy outside and inside,not those normal bullet that we see and it is quite long too...) have anyone seen that before? i have seen those in my hometown. In KL, i cant see those. This kind of bullet need to match the car ,else, no power gain. Thats all i can say :)

 

[kweng84]

Please take note that empty bullet (less than 10% fibre inside) will reduce ur pick up vastly.Please check every 3 months or less.

 

[theorekz]

kweng, regarding techinical... i'm not too sure... the boss is my dad's old friend... he has been in this field for more than 20 over years... spend most of his time working with matola as exhaust engineer(if not mistaken)... just recently came out n open his own exhaust shop,,,

 

[kweng84]

theorekz: i also learning from those who have much experience on the exhaust and maybe im wrong and need to be correct too..anyway, thats much i can say about exhaust from what i see with exhaust moddings in other ppls car and the feedback. There is where i have my analysis. Anything , just share with me about exhaust..

 

[markii]

u mean swieling bullet?can i use 2 different swirling bullets which are different brand but same design? how do i place the bullets?1 after another?