Skyline R33 GT-R Making of Air Cleaner Heat Shield

The bare type air cleaner has the problem of sucking hot air. I thought that I wouldn’t mind if I was running with a duct for guiding the wind. However, looking at the ECU data and logs, it was found that even during high-speed cruising, air with an outside temperature of + 20 to 25 ° C was inhaled. In the intake air temperature correction, when the temperature rises by 20 ° C, the fuel is thinned by about 4%, so it cannot be overlooked because the loss is -4 horsepower at 100 horsepower and -24 horsepower at 600 horsepower.

When I investigated why breathing hot air, the wind that hit the engine was heated by the fan and diverted to the side, hitting the air cleaner directly.

As a countermeasure, we will make a heat shield. Mold with thick paper.

I had a sheet metal shop in my neighborhood make it. Aluminum, which is easy to process, is good for DIY, but since it can be cut by a machine, I asked him to make it with a stainless steel plate. I made some adjustments and did some processing myself, but stainless steel is hard to scrape anyway! Aluminum plate is recommended.

I made a hole for piping of the boost control valve and a hole for mounting, and put a gold reflection sheet on the engine side. A door molding is also attached to the outer circumference so as not to damage others.

I thought I would fix it with a stay, but the lower part was unexpectedly fixed even if it was free, so I fixed it with a cable tie only on the upper part.

Install the air cleaner. This side has been buffed.

It is a photograph after installation.

It looks like it’s sticking out a lot, but there is a margin of about 2 to 3 cm between it and the bonnet. Originally I wanted to take a mold with the bonnet with clay etc. and fill the gap tightly, but this is enough. When I started the engine and put my hand near the air cleaner, I was able to confirm that the hot wind was blocked.

Actually run and check the effect. Is the temperature on this day around 24 degrees Celsius? The intake air temperature dropped to 32 ° C when cruising at 100km / h. The effect is outstanding.