Ok so this has been a long time in the making, but with my intake temps skyrocketing with summer my car has been pulling a lot of timing and I decided I had put it off long enough. I made a simple heat shield out of Lexan and some heat shielding mat that I purchased. The intake is a modified AEM short ram. The reason it is modified is I found the AEM short ram with it's 90 degree bend to be inconsistent when tuning. I would get everything tuned out perfect and it would change randomly. From what I have been able to learn, the 90 degree bend creates a little chaotic air going through the mass air sensor and results in inconsistent readings...thus tough to tune. I put a 45 degree bend post MAF sensor and had a straight shot leading to the MAF. I topped this off with an offroad K&N race filter. That made things infinitely easier to tune out the intake adjustments and it has been consistent since then. Then summer hit! All the sudden I was seeing some much higher intake temps. My car started pulling some serious timing out and just felt sluggish. While the heat shield will not solve this 100% it is already much better except when I am sitting in traffic. The first thing I did was to wrap the intake in the heat shielding mat. The only thing that was not wrapped was the MAF sensor. But the tube itself is now shielded. I then cut some lexan to go between the engine and the majority of the intake tube and to shield it and the location of the filter from the radiant heat of the engine. I coated the lexan in heat shielding as well. I am debating cutting the stock "scoop" to direct cool air into the box and over the MAF. So far though my intake temps while moving have dropped about 15-20 degrees and it takes much longer to come up at stop lights and in traffic. I am pretty pleased with it. Kind of hard to get pictures of, but it also has a plate on the side towards the firewall. The last step will be to create some type of seal with the hood.
Very nice. Some advice if you aren't doing it. My heat shield is very similar. I added the stock funnel thingy that sits on the radiator and cut it to direct air right on to the filter and the MAF. It helped just as much more
You know I was considering doing that and have not yet. I have to cut the factory piece and have been trying to keep my factory stuff intact. But hearing that I just might do it.
Well made some adjustments. I found that by taking off the heat shield mat that I put on the intake tube I was able to reduce the time it took to recover from heat soak. Also after the recommendation by CoolRex I cut into the factory scoop and installed it to direct air towards the filter and the MAF. Hopefully this helps things out even more.
Greg has made one of these for his STi out of carbon fiber. not sure if it has as many features tho...
I didn't know you could put a cone air filter thingie in a Subaru, I thought it had to be one of the flat ones in the box.
Well this started out as an AEM short ram intake with an AEM filter. I switched over to a K&N race filter. even with the AEM out of the box it is much better to get it tuned for as it is a 70 mm mass air housing vs the factory 65 mm. This means you really HAVE to retune.