(G) filter box hose

i've got to ask thise... i searched but didnt find the answer...

why have some of you removed these???

i took mine off today and went for a drive and to be honest the only change i noticed was my car was more sluggish....

sorry if its a stupid question.

Are you talking about the hot air pipe or front cold air pipe?

the one that goes from the mainfold to the air box

Oh. I remove it in summer, and have it in winter for times when I'm doing short trips only.

Mines a carb though, so no sensors or anything to alter timing/maps if conditions change.

i still dont really get it..... are you saying i should get a kind of boost by removing it on mine???

Dunno!

It's there to help warming up from cold start. It's effectiveness also depends on the flap inside the airbox.

The pipe that runs from the exhaust manifold to the airbox is actually there for a good reason. In cold conditions it allows hot air from the manifold to enter the airbox and make engine warm up quicker. It also helps stop carburetor icing from occuring and maintains a constant temperature for the incoming air.

Inside the airbox is a thermostatic flap that is supposed to regulate incoming air temperature. When the incoming air is very cold, it closes the cold air feed to the airbox and only allows hot air drawn from the manifold to enter the carburetor. Once the engine has warmed up it then opens the cold air flap so that colder (and therefore more dense) air can enter. More dense air allows better combustion hence more power.

For about 8-9 months of the year it is not really needed, though with the English climate you'd be surprised at how much it can make a difference.

People who fit performance air filters have to remove it as aftermarket filters don't normally have a provision for a hot air inlet. However, those running carburetors often find that as soon as the air gets damp and close to freezing carburetor icing can occur.

When the temperature is warm, colder air entering the carburetor can improve responsiveness and liberate a small amount of power. But as soon as the weather gets cold it can cause problems such as icing and making the engine take longer to warm up.

Probably the best thing to do is to remove it during the summer and/ or if a performance air filter is fitted, then refit the hot air pipe with the standard airbox during the winter.

Just by removing it on a standard airbox is unlikely to show any increase in power. All it will do is make the engine take longer to warm up once the weather has cooled.

If you have the i.e. version this hose has no or very little effect. The SPi doesn't suffer from "carb icing". It's not a carburettor either, but a semi-carb-injection.

Believe me, as my Uno starts and runs fine in minus 25 degrees Celsius with a good battery. So no need for this hose.

But it's there for a reason especially on the carburetted engines.

M.