Intercooler Info


After a LOT of thinking I decided to bite the bullet and replace my chargecooler setup with a front mounted intercooler in the hope it would prove more efficient and also to make my engine ready for the future mods I had planned. Also helped free up some room in the already cramped engine bay for me.

There are quite a few intercooler already on the market but none were suitable for me. Fussy bugger ?? Mebbe but I wanted to keep the car looking as standard as possible at the front and all the existing intercoolers were so deep that the bumper would have to be literally thrown away for it to fit.


So it was done. I pulled the front bumper off, which turned out to be the first of MANY MANY times it was to come off, and got to measuring and deliberating and drinking tea.


After literally hours of thought the idea was drawn and, in a fit of madness it was sent off to be made and, after around 2 or 3 days it came back looking the part - 









  intercooler1.jpg (27616 bytes)  intercooler2.jpg (32405 bytes)
(click for bigger pics)


Now this was the easy bit.... in fact, compared to the fitting of the intercooler, the design and general faffing around was a walk in the proverbial park.

Firstly we need to mount the intercooler which was relatively straight forward enough and helped to boost the old confidence factor that this will work..... Kinda led me into a false sense of security more like !!!!

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Easy enough..... Now the fun starts. Obviously it wouldn't fit without cutting a bit of the bumper so, now that the intercooler is mounted, its time to get the bumper cut so it will go back on unless I want stopped by the police all the time ;)

Firstly, the coloured section was removed from the black backing and a hole cut in the black backing to take the intercooler - 

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With this section removed (you don't see it anyways as its hidden behind the coloured panel) the bumper skin wrapped neatly around the intercooler...... Yeah ok, after a a lot of minor alterations (basically I went mental with the Dremel) -

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Ignore the fact that the top section of numberplate area has been removed (the bit where you can see the screws) as this has been changed so that only the bottom half is missing to allow airflow to the top of the intercooler.

Now comes the delicate part.... so delicate I wimped out and got someone to help as they had done it before (cheers Russ). The bit I am talking about is the trimming of the coloured scoop of the bumper. 

Around 1-1.5 inches had to be trimmed back so that the bumper could go back on. This was reason I chose to get a custom intercooler made up. I knew some of the bumper would have to go but, with the one I designed, it kept it to a minimum whilst still having a VERY effective intercooler (see power run results later).

As you can see, you hardly notice that the scoop has been trimmed at all - 

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Now that the "tricky" bit was past (or so I thought) I concentrated on getting the intercooler plumbed in..... After all, it would be no good to me just having that great hulk of metal sitting there doing nowt.

The pipework was relatively easy once it was figured out...... Aint it amazing how what you think things should go like and how they actually do go like are totally different ??

First off, the standard intercooler had to come off to allow the pipework of the new cooler in. This involved removal of the radiator/intercooler unit and then splitting the unit apart to remove the intercooler. This was all done easily enough

Now onto the actual pipework - 

The main stumbling block here was, surprisingly, not really my fault although I should have thought about it as we are talking about the masterminds of Vauxhall here. I had assumed (first mistake) that Vauxhall would be using 50mm diameter pipework for the standard induction path and so had bought all the hoses in that diameter. I also acquired the metal piping needed from my brother in 50mm as well.

So here is me, under the car ready to start fitting the pipes. I was going to use the existing turbo "down pipe" which was a 90o bend and simply rotate it through 180 to attach it to the rest of the new pipework (2nd mistake) This is where it got interesting.

As mentioned above, I had assumed Vauxhall to use the standard 50mm piping all the way through. Not chuffing likely !!!!

What the "boffins" at Vauxhall had decide to do was to take the 50mm turbo exit and use a reducer on the 90o bend I was going to use so it dropped it to 45mm.... I mean they went to all that hassle to drop the poxy induction pipework bore by a lousy 5mm !!!!

So here is me with a 50mm metal pipe and a 45mm end.... What to do. I needed the car the next day as it was going to Aberdeen (see Unichip story) After more cups of tea I called Russ. He happened, as always, to have the answer - a spare bit of 50mm 90o bend hose that I could blag. Now, how to get the 30 miles to his place.......

I decided to try my best so I slit the 45mm end at the 2 sides and forced it onto the metal pipe. Not surprising, the hose blew off under boost so I had to put me thinking cap on and within minutes I had the answer...... DUCT TAPE!!!! 

I forced the pipe back into the hose and wrapped LOTS of duct tape around it to stop it moving out. This got me far enough (Russ's house) to get the spare pipe and, after 30 mins, the job was done and the custom intercooler was fitted and working great =)


Was it worth the hassle ??

Check out below - 





Chargecooler V Intercooler

A topic that has caused some debates recently (and in the past) has been What is best -  fitting a chargecooler OR a front mounted Intercooler to your forced induction car ??

Well I like to think I am now in a position to help you decide after having both devices added to my own Cavalier Turbo independently of each other.

First off, lets describe the main differences between a chargecooler and an intercooler for the benefit of everyone. Both devices have the same aim which is to reduce the temperature of the charge air between the turbo and the inlet manifold. This increases the charge density and therefore more power is produced.

The cold air also reduces the potential for pinking or detonation within the chamber and so preventing engine damage.


A chargecooler is a water-to-air heat exchange device which uses cold water as the medium to transfer heat from the charge air that has come from the turbo and thereby reducing the charge temperature before it reaches the inlet manifold.

The water is then re-cooled by passing it through a small radiator at the front of the car.

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Heat Exchanger where heat transfer
 takes place in the Chargecooler


This is an air-to-air heat exchanger which uses the surrounding air to cool the charge by forcing it through a large radiator type device.

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Intercooler shown in scoop area


So now that we understand how it all works lets get straight onto the results -

Standard car

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Car at 204BHP and 218lb/ft  


Standard Car with Chargecooler

 rr_report_large_220bhp.jpg (224339 bytes) 
Car at 220BHP and 235lb/ft

The car has gained 16BHP and 17lb/ft of torque with just the chargecooler in place.


Standard Car with Intercooler

rr_report_large_238bhp.jpg (168927 bytes)
Car at 239BHP and 243lb/ft

As you can see here, with the car having the intercooler only (chargecooler was removed) it gained a phenomenal 35BHP and 25lb/ft over standard.


I don't think I need to explain any further. If you have the ability to squeeze an intercooler behind the front bumper of your car and you allow unrestricted airflow to the intercooler then you will see exceptional gains in power and driveability.



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