Nodge68
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Would you like to get a bit more power out of your 1.8 or 2.5 petrol engine Freelander without spending a fortune? Is that even possible you ask? Yes is the answer! If you want to know how? Read on and I'll show you 
I'll be doing this in stages over the next few months so if you are interested keep a look out.
First off I'll look at how to get power for almost nothing.
Have you ever noticed that your Freelander seems to have a bit more power on a cold and crispy winter morning? There is a reason for this, it's all to do with air density, the colder the air an engine can ingest the more oxygen it will contain, the higher oxygen content can burn more fuel which will equal more power.
So how do we get colder air into the engine? It is possible to to do with a little ingenuity and some insulation.
There is a rough calculation I use to work out how much power a high intake temperature can rob from an engine. For every 5ºC increase in temperature 1hp will just dissappear into thin air!
I'll use my V6 as an example of what is possible.
I've spent many hundreds of miles recording all the live data for later analysis but one thing that stands out is just how high the inlet temperature is, it's not uncommon to see the engine consuming air at over 50ºC when the ambient temperature is only 20ºC! Now by my formula my engine is loosing 6hp. In real terms it's probably loosing more like 10hp but I'll say 6hp for simplicity.
So how do i get the inlet air temperature to as close to ambient as possible? Insulation. The V6 has an air filter housing mounted on top of the engine presumably because there was little space around it to put an air filter box, this causes it to absorb huge amounts of engine heat through the trunking which is then passed to the air which is on it's way to the engine. I added some of that silvered insulation that is used behind a domestic radiator to stop the wall absorbing the heat. This is a pretty easy task to complete, I also changed the air filter while I was there. From the testing carried out so far I've seen more than 20ºC drop in inlet temperature so this is a well worthwhile mod.
The 1.8 filter box is rather susceptible to heat from the rad and exhaust so wrapping that in insulation will have the same effect reduced inlet temperature.
Here are some pictures.
I'll be doing this in stages over the next few months so if you are interested keep a look out.
First off I'll look at how to get power for almost nothing.
Have you ever noticed that your Freelander seems to have a bit more power on a cold and crispy winter morning? There is a reason for this, it's all to do with air density, the colder the air an engine can ingest the more oxygen it will contain, the higher oxygen content can burn more fuel which will equal more power.
So how do we get colder air into the engine? It is possible to to do with a little ingenuity and some insulation.
There is a rough calculation I use to work out how much power a high intake temperature can rob from an engine. For every 5ºC increase in temperature 1hp will just dissappear into thin air!
I'll use my V6 as an example of what is possible.
I've spent many hundreds of miles recording all the live data for later analysis but one thing that stands out is just how high the inlet temperature is, it's not uncommon to see the engine consuming air at over 50ºC when the ambient temperature is only 20ºC! Now by my formula my engine is loosing 6hp. In real terms it's probably loosing more like 10hp but I'll say 6hp for simplicity.
So how do i get the inlet air temperature to as close to ambient as possible? Insulation. The V6 has an air filter housing mounted on top of the engine presumably because there was little space around it to put an air filter box, this causes it to absorb huge amounts of engine heat through the trunking which is then passed to the air which is on it's way to the engine. I added some of that silvered insulation that is used behind a domestic radiator to stop the wall absorbing the heat. This is a pretty easy task to complete, I also changed the air filter while I was there. From the testing carried out so far I've seen more than 20ºC drop in inlet temperature so this is a well worthwhile mod.
The 1.8 filter box is rather susceptible to heat from the rad and exhaust so wrapping that in insulation will have the same effect reduced inlet temperature.
Here are some pictures.
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