When doing a custom supercharger fitting job there is always some starting point. Of course I had to start with a prototype that worked but was not visually nice. Some portions of the prototype bracket still need some fine tuning for excellent fitment and prevent cables/wires or pipes to rub against it.
Although this bracket was design for the MY00 Impreza 2.5RS, I intend to do another for the MY04 (if ever I can find the time). It should be fairly similar but one major problem is that the intake manifold for the 2004 Impreza 2.5RS is made from some sort of plastic. I believe this was done to increase thermal insulation hence keeping the intake cooler. Since it is not made from aluminium, I am not expecting to be able to bolt easily the supercharger bracket onto it. I will need to find bolts location (free or not) surrounding the manifold that I could use to hold the upper part of the supercharger bracket assembly.
Let's get back to the prototype I made for the MY00 2.5RS. The most difficult part was to make the bracket such that it will flex to a minimum under the various engine load conditions. I had to add some reinforcement at key locations to prevent this. Any variation in belt tension could lead to slippage. Belt splippage will make the boost erratic, and will shorten the life of the belt...not to mention terrible noise ;P
The bracket is made from steel, mainly because it doesn't cost a lot and is easy to find. Aluminium would have been lighter but to obtain the same rigidity I would have needed to use specific type of aluminium. The cost of aluminium is generally more that plain steel. Another good point is that I have no equipment to weld aluminium and never welded aluminium (but I would love to learn how to).
I used pretty tough angled steel pieces to ensure that there would be no flexing. The supercharger is not as heavy as a M90 unit but the M62 is not that light either.
My kit is far from perfect and not totally to my taste. As of now I do not have a way to adjust the tension of the belt driven by the S/C. Another thing to note is that in order to driven the S/C I installed a pulley on top of the steering pump pulley. As you can see on the pictures below this is not ideal but it is functional. This is still a lot of room for improvement.
Although this bracket was design for the MY00 Impreza 2.5RS, I intend to do another for the MY04 (if ever I can find the time). It should be fairly similar but one major problem is that the intake manifold for the 2004 Impreza 2.5RS is made from some sort of plastic. I believe this was done to increase thermal insulation hence keeping the intake cooler. Since it is not made from aluminium, I am not expecting to be able to bolt easily the supercharger bracket onto it. I will need to find bolts location (free or not) surrounding the manifold that I could use to hold the upper part of the supercharger bracket assembly.
Let's get back to the prototype I made for the MY00 2.5RS. The most difficult part was to make the bracket such that it will flex to a minimum under the various engine load conditions. I had to add some reinforcement at key locations to prevent this. Any variation in belt tension could lead to slippage. Belt splippage will make the boost erratic, and will shorten the life of the belt...not to mention terrible noise ;P
The bracket is made from steel, mainly because it doesn't cost a lot and is easy to find. Aluminium would have been lighter but to obtain the same rigidity I would have needed to use specific type of aluminium. The cost of aluminium is generally more that plain steel. Another good point is that I have no equipment to weld aluminium and never welded aluminium (but I would love to learn how to).
I used pretty tough angled steel pieces to ensure that there would be no flexing. The supercharger is not as heavy as a M90 unit but the M62 is not that light either.
My kit is far from perfect and not totally to my taste. As of now I do not have a way to adjust the tension of the belt driven by the S/C. Another thing to note is that in order to driven the S/C I installed a pulley on top of the steering pump pulley. As you can see on the pictures below this is not ideal but it is functional. This is still a lot of room for improvement.
