Exhaust Query

[Unregistered_User]

Hey there everyone,

Just wanted to ask some questions relating to exhaust systems...

For those that have cat-back exhaust systems fitted, do you have any issues relating to engine idling? For example, with the standard exhaust your engine idled at 1k, but now with an aftermarket system fitted, it idles at 1500?

Any uneven engine idling?

Any spluttering?

The reason I ask this is that I have never had a simple exhaust system fitted to a car. My previous car (Ford Focus 1.6) had the first 4-2-1 branch manifold fitted in the country, along with a decat exhaust system and rally profile cams.... As a result, the engine idled like a bag of spanners. Absolutely awful, but was the price to pay!

Any tips, hints and suggestions are all welcomed.

Many thanks,

Jamie

[corsavandal]

I've just put an HKS cat-back on my S and nothing like that. it does idle just over 1000 rev's but its still considerabley less than 1500. It was the same on my Corsa with a powerflow cat-back.

The slightly higher idle is nice though as you hear the exhaust puuuurrrr away whilst sat at lights etc. :winky:

Havent a clue what effect a system from the manifold to back box would have though as i've never ventured that far into exhaust moding.

[tdiplc]

Hi Jamie

Changing the exhaust should not effect the idle speed or quality.

The issue with your Focus is more to do with the camshafts you installed having longer duration and valve overlap.

Hope this helps

Mark :)

[CIJ]

Alright mate,

When i put the HKS back box on i had no idlin problems, my car idles below 1K, around 500-600 even with the manifold changed!

Chris

[Rob's Lexx]

if you let it run for a little mate, the idle revs should drop back to normal. could just be cause its cold and the idler needs time to get back to its normal level

[Rikos]

I agree shouldny be any change may just need bedding in fella

[Unregistered_User]

So far so good with regard to replies. I haven't had the system fitted just yet, but was a little warey and just wanted to clarify.

Is this the same if the IS200 is fitted with both a cat-back system and a manifold, or are we entering into another subject here? Air/fuel/lean etc.? Causing further issues?

Cheers,

Jamie