This guide will show you how to remove the boost return pipework from your Corrado G60 and explain the reasons for doing so. If you have any questions you can leave a comment.
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Removal of the boost return pipework is a very common G60 modification. So why is this done? Originally the purpose of this pipework was for emissions recirculation, with the downside being that recirculated dirty and warm air is fed back into the G-Lader supercharger, and we all know that reduces power in two ways. Firstly warm intake air is not as dense, and secondly dirty (Oily) misting of the intake air reduces ignition efficiency. The upside? Well the Corrado G60 passed emissions regulation tests back in the late 80's through the 90's.
NOTE: In no way does the boost return provide any lubrication to the G-Lader supercharger. Once this modification is carried out, there is absolutely no need to spray anything into your supercharger. It can actually cause damage to the lambda sensor and the supercharger itself. The apex strips (Seals) within the G-Lader contain PTFE, hence they are self lubricating.
Thankfully removing the boost return is easily done, and only a few tools and parts are required.
NOTE: The bottom of the throttle body can safely be left open.
Tools and parts required
- Flat head screwdriver for jubilee clips
- Allen key for detaching from supercharger
- Alloy supercharger blanking plate
- Catch tank (Optional)
- Long breather pipe for rocker breather (Optional)
- Small K&N style air filter (19mm Internal diameter)
Removing Boost Return
- Firstly you need to remove the main boost return pipe. This is pictured orange in the image. This pipe runs from the bottom of the throttle body, past and connecting to the idle stabilisation valve (ISV), past and connecting to the rocker cover breather pipe and finally terminating at the right hand side of the supercharger.
- Next, you need to fit the small K&N style filter to the idle stabilisation valve (ISV).
- Lastly you can either run a long breater pipe from the cam cover breather and tuck it safely out of the way to ensure fumes will not enter the interior of the car. Or...You can fit a catch tank with an integrated air filter. What you should end up with once the boost return is removed is shown in the second image.
Last update: Mon, November 09. 2015
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