Kaidan117

greetings CL! I am having an issue with my rc350 after installing my catback ARK exhaust. Whenever i try to come
to stop after going over 35mph the rpm fluctuates up and down between 1000 to 3000rpm about 3 times and i would hear a back fire from my exhaust. If anyone ever come across this problem and know a solution for this please help me out. Thanks in advance!

FR500GT

iTrader: (7)

How long has it been since you've had the new catback installed?

Kaidan117

had it for 2 months now... it just fluctuates once i started to come to stop and once im on idle it doesnt even fluctuates at all... its playing around 1k to 2k rpm correction above and then backfires... no stalling or any hesitation at all...

mjeds

is it down shifting?

typically aftermarket exhausts will cause what is known as a deceleration pop, and the fluctuation sounds like the car is simply downshifting.

is it something like this:

around 45 seconds in the video:



per the video:

A well-tuned engine should ignite excess fuel in the exhaust manifold, especially under load, during abrupt deceleration. The excess fuel is a direct result of the abrupt closure of the throttle which pulls a vacuum causing the A/F mixture to burn slower, therefore generating less heat. This allows the exhaust to open longer which dumps more unburnt fuel into the manifold. Despite what some may think, this is the normal state in which an engine and exhaust system operates. You can de-tune an engine by running the engine rich (this is the correct term as you are forcing that otherwise waste fuel to remain in the engine). If you removed the stock mid pipes, you would hear this on every factory car as no manufacturer that I know of would force an engine to run rich constantly just to mask some noise. They have resonators and mufflers for that purpose

Megafast13

It is downshifting.

mjeds

kids eh? .........

Kaidan117

Couldnt really hear it but i hear the pop and its about the same but it only does that when im slowing down and come to stop.

mjeds

all engines do it, the OEM exhaust is designed to hide it, aftermarket exhaust don't, you wanted louder, you got louder. .


as stated under the video:

A well-tuned engine should ignite excess fuel in the exhaust manifold, especially under load, during abrupt deceleration. The excess fuel is a direct result of the abrupt closure of the throttle which pulls a vacuum causing the A/F mixture to burn slower, therefore generating less heat. This allows the exhaust to open longer which dumps more unburnt fuel into the manifold. Despite what some may think, this is the normal state in which an engine and exhaust system operates.

Sim

The cracks and pops are the best part of the Ark exhaust! lol

Did you research what you were getting into when you decided to get a performance exhaust?

Kaidan117

well i did as far as the perfomance exhaust but didnt really expect what i have now lol... as long its nothing to worry about im good cos i love the way it sound.

Thank you all for the info!