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Post by siuyi (10) on Aug 7, 2009 1:53:05 GMT -8
kuriek59
sell off ur spare tyre...at least rm100 ar.. ;D
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Post by almostthere on Aug 7, 2009 3:56:31 GMT -8
I beg to differ those are mere small design restriction and will not affect much although it does play a part in restriction, if u do your research properly u will see the catcon is the biggest culprit(google), if u take a look at the catcon inside, its honeycomb design, imagine those exhaust gas trying to squeeze through that. Most ppl will remove the catcon 1st for obvious reasons and not all cars header and catcon are together so they have the luxury to keep the stock header and just remove the catcon. That's rather a myth rather then a reality. According to many dyno tests done before be it locally or overseas, the differences in volumetric gas flow with and without the cat is marginal unless we're talking rather massive exhaust pressure flows especially from larger cubic capacity engines. For our type of engines, it's more related to the design of manifold itself. From my observations, the stock headers are not even pulse optimised as if we observe carefully, P1 had to create an exapnsion chamber (the bulge near where the O2 sensor is located) in order to equalise the pressure diffrential between exhaust pulses. If you measure the cross sectional narrow down, the stock design is rather ridiculous to say the least. Take again chamber 1 and 2, the effective mean cross sectional passage drops down to the point it's almost the the equivalent to a single chamber passage way cross sectional path. Chamber 3 and 4 is another story by itself. The flow path is more equalised (but honestly not by much) but by observing the joining path between chamber 1-2 and 3-4, it's definitely going to cause turbulent flow and possible blow back. While this is good for emissions as it acts as a semi EGR, we all know that reduced oxygen content in the combustion will rob the engine of it's maximum energy conversion potential. As for the cat con, the only way nowadays to maximise the gains itself from ridding the cat con would definitely need a reprogram of the injector cycles mappings as modern day ECU's are programmed to run richer at stoichiometric point to maximise the reactor catalytic process itself. So therefore we're not reaching full potential just yet. In fact IINM, Hypertune did a project car on an E46 and noticed upto a 5bhp drop removing the cat (dyno proven at Jaafar's) and needed a reflash of the main ECU chip to corrrect that out. Don't worry for our though as the Siemens ECU is a closed loop design so it'll self correct accordingly. But we can stilll safely conclude a free flowing exhaust is much better, what more a mandrel bent since the cross sectional area would be more constant. |
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Post by Storm(02) on Aug 7, 2009 4:59:37 GMT -8
Haha well said bro nway proton r&d is for economical reason thats why i changed everything, but our siemens a bit cacat one , once reach 3.5k rpm the ecu goes open loop and run as rich as it can dono whats the reason behind it some say the o2 sensor is unable to keep up with the constant changes at high revs therefore bypassing it. Nway we should discuss this on other thread this is bazaar section.
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Post by almostthere on Aug 7, 2009 5:51:43 GMT -8
Haha well said bro nway proton r&d is for economical reason thats why i changed everything, but our siemens a bit cacat one , once reach 3.5k rpm the ecu goes open loop and run as rich as it can dono whats the reason behind it some say the o2 sensor is unable to keep up with the constant changes at high revs therefore bypassing it. Nway we should discuss this on other thread this is bazaar section. Agreed but best to discuss over a cuppa coffee. I have the explanation to the so called cacat part and it's not the O2 sensor's reason. The sensor is what we call a feedback unit and there's no such thing as keeping up. Think back about the 2nd para of my explanation. Think stoichiometric point and the answer is there |
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Post by karmicsaga(16) on Aug 7, 2009 7:34:14 GMT -8
wana change but plan to change after changing my iafm for th 2nd time ....
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Post by vodafone (zero-five) on Aug 8, 2009 3:10:25 GMT -8
bro... 2 fast lar... give 1 more time la... selain 8.8...
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Post by kuriek59 on Aug 8, 2009 4:17:38 GMT -8
mahihi, i'm interested but lack of penny right now...  sell ass then got $$ ad.. WTF man....  must ask syuk 1st where to sell wooo..  |
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Post by -Hzai- (50) on Aug 8, 2009 5:20:59 GMT -8
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Post by vodafone (zero-five) on Aug 8, 2009 10:08:09 GMT -8
i miss...
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Post by Storm(02) on Aug 8, 2009 19:19:38 GMT -8
Haha all the guys who went all change full set exhaust at discounted price.
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Post by karmicsaga(16) on Aug 8, 2009 19:30:07 GMT -8
wah dats cool i knew it that was sure going to happen !! ow much was the full set exhaust system?? and how is the feeling of the new exhaust ??
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Post by Ronnie (125) on Aug 8, 2009 20:21:08 GMT -8
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Post by -Hzai- (50) on Aug 9, 2009 0:34:28 GMT -8
emo la..have to eat roti kosong for few month
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Post by karmicsaga(16) on Aug 9, 2009 3:04:38 GMT -8
how much how much  ?? it cost youll |
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Post by Storm(02) on Aug 9, 2009 4:14:12 GMT -8
Lol the price is too painful to say =p
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Post by kuriek59 on Aug 9, 2009 4:26:39 GMT -8
Lol the price is too painful to say =p iyer ker??? mahihi said its cheaper than others shop...how? |
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Post by mahihi 88 on Aug 9, 2009 4:58:14 GMT -8
merl said dat to avoid other club go and kacau the shop to get same price,i have decided not to post the gps location of the shop,ur all reach wangsa maju the royal selangor factory there ad,then call storm,will be better
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Post by karmicsaga(16) on Aug 9, 2009 5:49:06 GMT -8
maybe u can pm me plz plz plz !!
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Post by ::fuZzYwuZzY:147:: on Aug 9, 2009 7:18:37 GMT -8
i think i saw sumting about changing the whole exhaust system at discaounted price..how much!!??..  ..if dun wanna tell open²..pm me lor..hehe...(cheapskate in action!) |
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Post by vodafone (zero-five) on Aug 9, 2009 8:30:25 GMT -8
kuriek... aku nak ikut ko g sane leh? pm me k bro...
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