Teach this man!

Kevv_Si

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Hey guys! Soo got my downpipe today and my pops was over and asked why I wasn't installing it. Well you know I told him I'm not installing until I tune the car...well he laughs at me and tells me that I don't need a tune to run the downpipe. I tried to explain to him that our ecu work against our mods and try to compensate for all the extra air flow etc, well he says the ecu doesnt do none of that blah blah blah (he used to have built integras, civics, and a rsx) soo basically can someone else chime in with an explanation as to why me adding the downpipe now well just result in my car running like ****.
 

squiggy

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Hey guys! Soo got my downpipe today and my pops was over and asked why I wasn't installing it. Well you know I told him I'm not installing until I tune the car...well he laughs at me and tells me that I don't need a tune to run the downpipe. I tried to explain to him that our ecu work against our mods and try to compensate for all the extra air flow etc, well he says the ecu doesnt do none of that blah blah blah (he used to have built integras, civics, and a rsx) soo basically can someone else chime in with an explanation as to why me adding the downpipe now well just result in my car running like ****.

Just ask him what you should do when the CEL comes on then.

When you say used to, how long ago would that have been? There have been some pretty big changes in air flow design even coming from the 8th gen to the 9th...mainly due to emissions.
 

Michal006

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Car will feel sluggish and you will probably sacrifice your mpg too. That's the worst part about new cars. Wait till you get any modern turbocharged car it's even worse.
 

Kevv_Si

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Just ask him what you should do when the CEL comes on then.

When you say used to, how long ago would that have been? There have been some pretty big changes in air flow design even coming from the 8th gen to the 9th...mainly due to emissions.
Well he had an all motor 04 rsx dyno'd at 230whp, a boosted integra, and a couple hatches and a 99 em1.
 

Kevv_Si

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He basically says I will not lose power at all. He doesn't say I shouldn't tune it ...just that I can run the downpipe without a tune.
 

squiggy

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Well he had an all motor 04 rsx dyno'd at 230whp, a boosted integra, and a couple hatches and a 99 em1.

So he is projecting knowledge from 10+ year old cars and two generations ago?

Essentially, the car has certain parameters it must stay within for emissions. If you alter anything affecting emissions, the ECU will add/remove air and gas to try and get it back within those parameters. The ECU does not care about the performance of the car in any way as long as it is within emissions parameters and not making any adjustments that will damage the engine.
 

squiggy

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He basically says I will not lose power at all. He doesn't say I shouldn't tune it ...just that I can run the downpipe without a tune.

It is not about losing power. It is about running the engine too rich or too lean for an extended period of time. I ran the car for about a week without a tune and it threw a CEL and felt sluggish. Then I got a FlashPro and used the ReFlash with my dp/exhaust until I got a tune. That was about a month maybe. My exhaust tip was covered in soot due to how rich it was running. I initially thought the car ran much better because the rev hang was gone, the throttle response was better, and the jerkiness was gone. Boy was I wrong.
 

Kevv_Si

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It is not about losing power. It is about running the engine too rich or too lean for an extended period of time. I ran the car for about a week without a tune and it threw a CEL and felt sluggish. Then I got a FlashPro and used the ReFlash with my dp/exhaust until I got a tune. That was about a month maybe. My exhaust tip was covered in soot due to how rich it was running. I initially thought the car ran much better because the rev hang was gone, the throttle response was better, and the jerkiness was gone. Boy was I wrong.
Thanks that's all I need lol. And he's not he just doesn't get these new ecus.
 

Nix

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You can also point out to him that you used to be able to swap seats without issue. Now if you do that your airbag light will be on and none of them will work. There have been massive changes made to cars in the last 10 years. Ask him about that TPMS setup he used to run? Oh right.... more electrical and computer controlled changes. Since now if your TPMS light is on you can't disable the traction control. So yea, certain things need to be addressed properly on the new cars since the computers are in control of a lot more of the cars functions than they used to be.

It's that simple. The computer is in charge and unless you have a way to control it, FP, you will not be able to do the things you want correctly.
 

Kevv_Si

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You can also point out to him that you used to be able to swap seats without issue. Now if you do that your airbag light will be on and none of them will work. There have been massive changes made to cars in the last 10 years. Ask him about that TPMS setup he used to run? Oh right.... more electrical and computer controlled changes. Since now if your TPMS light is on you can't disable the traction control. So yea, certain things need to be addressed properly on the new cars since the computers are in control of a lot more of the cars functions than they used to be.

It's that simple. The computer is in charge and unless you have a way to control it, FP, you will not be able to do the things you want correctly.
Can't wait till mine gets here.
 

jarvasdb1

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Hey Squiggy, when you threw a CEL did you have a CEL eliminator on it as well? Hey Kevv, apparently your dad and I are from the same era. I miss the days of having a header made you a serious competitor on the streets. The pic I use as my wig/avitar was taken in '99. I used to hold my own on the streets of Nor Cal. Then I retired from the scene. 2 kids and well over a decade later I am back.
 

Bulkybear

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Downpipe will cause the stock ecu to lean out or possibly over fuel, ruining power and gas mileage and flooding the engine really bad due to increased o2 in the exhaust path, especially if catless, and will cause the car to pull any timing advance. If the car does by chance run after that it will be barely and with a check engine light due to out of wack o2 readings.
 
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