Decat on Standard Exhaust .. fueling need addressing?

[Tim]

Conisdering fitting a decat to the car in an attempt to keep exhaust temps down more than anything, but was wondering if i'd need to address fuelling when i fit the decat?

Mine is a standard 1994 car on standard boost, airbox, exhaust, etc, etc.

Regards

Tim

 

[campbellju]

doubt it will make much difference to fueling and generally the aim is to keep exhaust temps up not down. What is your reasoning?

 

[Tim]

As i understood it, the cat is a bottle neck in the exhaust system, causing more back pressure than desired, thus increasing exhaust and engine bay temps?

The less heat generated by the exhaust/turbo, the less work the intercooler has to do to keep charge temps down..

Or am i completly wrong here?

 

[Trip]

Keeping the exhaust gasses hot will help the gasses exit faster (without the cat). If you want to address heat radiation, wrap the manifold, down pipe and elbow with exhaust wrap.

 

[PobodY]

The turbo and exhaust don't generate any heat; if anything they take it away. - It's all that petrol burning in the cylinders that makes heat!
The catalytic converter is a bottle-neck in the flow of hot gasses, yes. It needs to be hot or it won't catalyse the cracking of the hydrocarbons (mainly PAH - poly aromatic hydrocarbons I think) to the less toxic short-chain products... and that's what we're supposed to do to keep the environment nice and free from carinogenic combustion by-products (sorry; I work in Environmental testing).

Better flow away from the turbo should in theory keep the engine bay (and intercooler) less hot, but to be honest that's nothing compared to the benefit of having a pressure drop across the turbine (the bigger the pressure drop, the more it will spin).

Anyway, you don't need to worry about the fuelling etc because that's all on the other side of the engine!