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Intercooler Upgrade

By all reports, the OEM intercooler for the 20B isn't really up to the job (280 CFM). So I decided to install a larger intercooler with more flow.
The intercooler I went with had the following specs:

MAZDA SERIES 6 RX-7 BOLT-ON INTERCOOLER
Core Dimensions: 450mm X 300mm X 85mm
Overall length of 630mm
All TIG Welded 6061 Aluminum, polished end tanks
100% Vacuum Brazed Core 
High Efficiency Bar & Plate Construction 
2.5 inch Inlet and Outlet 
Max Recommended PSI: 45psi 
Low pressure drop w/ only 0.2psi at 15psi of boost
Tested CFM: 1020 CFM

 

 

The original and the new intercoolers:

 

 

So I removed the top shroud, the front grill section (4 x 10mm bolts ans 2 x push-in clips),the hood opener (2 x 10mm bolts and 1 x 10mm nut) the inlet pipes and lifted the intercooler out. The obvious things in the way are the 2 horns, which were removed and a temp sensor which was unbolted and reinstalled at the end of the upgrade.
The horns each had a mounting bracket that were obviously going to get in the way of the new piping. These 2 brackets were ground off with a 4" grinder. Note the picture shows the passenger side bracket half cut away.
The lower forward protuding part of the bracket(where its welded to the chasis) also had to be ground away to ensure adequate clearance for the new piping.
Its always a good idea to splash a bit of paint on any bare metal.

 

 

These are the 2 brackets after removal:

 

 

Here's the "intercooler bay" with the horn brackets ground off and ready to start thee installation of the new intercooler.

 

 

I adapted some 90 degree angle brackets from Bunnings for both the bottom and top supports. I installed a strip of rubber so the intercooler was supported firmly and couldn't move forwards or backwards. A dab of sylastic was put on both sides of the rubber to reduce the chance of any sideways movement. Here's a pic with the bottom brackets installed onto the existing intercoller brackets (I used a 25mm washer to utilise the old mounting point):

 

  I bolted my manufactured brackets to the top original brackets so it would support the intercooler on the same principle as the bottom ones. The height was perfect!

 

 

Here it is all put back together:

 

 

Most of the parts used:

Cost:

Part Qty Amount
Intercooler 1 199
90 degree silicone bends 2.5 inch 2 44
45 degree silicone elbows 2.5 inch 2 44
2.5 inch SS pipe 300mm ??
2.5 inch hose clamps 8 20
3/16" screws & nuts    
Rubber strips 4 ??
90 degree brackets 8 7

Total Cost less than $350. Installation time less than 5 hours (now I know what to do!).

Tools required:
General hand tools and socket set
4" angle grinder
Electric drill