Added Insulation to AirBox
Thread Starter
Senior Member
Joined: 11-27-2007
Posts: 1,115
From: Austin, Texas
Added Insulation to AirBox
I have noticed that the airbox gets (not surprisingly) fairly hot, so spent some time insulating it and the short cold air intake. It now stays noticeably cooler to the touch.
In theory, it should improve initial throttle response after cruising at part throttle, since you don't get that initial shot of hot air. Likely has no effect on full throttle extended pull, since you are pulling in so much outside air, the box temp has no effect.
I also ducted cool air to the pipe from the IC outlet to the intake. All combined, I dropped the temp about 10 deg F to only about 6 deg over ambient under almost all conditions, so it really is an improvement.
Added a couple of washers at the 3 mounting studs to compensate for insulation thickness (foil+foam backing).
After I did this I had a P0234 "overboost code" for the first time ever, I hope that was just coincidental.
Not pretty I know. But also not the only "foil insulation" under the hood.
In theory, it should improve initial throttle response after cruising at part throttle, since you don't get that initial shot of hot air. Likely has no effect on full throttle extended pull, since you are pulling in so much outside air, the box temp has no effect.
I also ducted cool air to the pipe from the IC outlet to the intake. All combined, I dropped the temp about 10 deg F to only about 6 deg over ambient under almost all conditions, so it really is an improvement.
Added a couple of washers at the 3 mounting studs to compensate for insulation thickness (foil+foam backing).
After I did this I had a P0234 "overboost code" for the first time ever, I hope that was just coincidental.
Not pretty I know. But also not the only "foil insulation" under the hood.
Thread Starter
Senior Member
Joined: 11-27-2007
Posts: 1,115
From: Austin, Texas
Yeah, I debated that, but my theory was under full boost you probably don't want them insulated since you will likely be above the temperature of the engine compartment on the pre-intercooler side, so you would want them to "lose" heat. Right?
Thread Starter
Senior Member
Joined: 11-27-2007
Posts: 1,115
From: Austin, Texas
Yes, that is likely a good idea. I ducted cold air to the general area of the IC outlet instead, and combined with the reductions in temp of the turbo inlet air, the monitored IC outlet (IAT2 on the Aeroforce readout) is running 5 to 8 deg over ambient (outside air temp) at cruise or full boost. Prior to my changes it was running 15 to 30 deg F over ambient at cruise and 5 to 8 deg over ambient at full boost (high airflow overcoming heat-soak is why boost IC out is actually lower temperature than cruise).
