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I read an article in Auto Speed (March 2002 edition) that used a differential air temp gauge to look at air temps under the bonnet.
The test was on a stock LS400 (how convenient!) and showed that the temp difference between the ambient temp and the temp in the entrance to the over the radiator air intake to be 1degrees Celsius (all temps will be Celsius) when being driven and 3 degrees C when idling.
By comparison the under bonnet temp (where your average pod would draw) was 8 degrees hotter even when driving at 120kmh! When idling the temp rose to be 40 degrees hotter than ambient. The rate of rise was 3-4 degrees per second when idling.
When climbing a steep hill the under bonnet temp roe by 30 degrees. This all indicates a CAI will work wonders for your engine.
The test showed that under bonnet temps did not drop all that quickly when the car started moving. This tells us that a pod equipped car is sucking very hot air at the traffic light Grand Prix.
Further testing was done with a sensor inside the air-box. The temp was 4 degrees hotter in the air-box than at the inlet. This difference would rise to 12 degrees when the car stopped. The temp dropped quite quickly when the throttle was opened as cooler air entered the air-box. Conversely lifting off the throttle caused a rise in the air-box temp. Heat soak would no doubt keep the air warmer than it could be for quite a while. Does this mean if you have pre-ignition you shouldn’t back off as the inlet temp rises which will make it worse (lol).
The long and the short of this is it’s worth shielding your air-box and inlet pipes, throttle body and AFM from the heat of the engine bay in addition to feeding it the coldest air you can find if you want ultimate performance your engine can give.
Splitting hairs, being pedantic? I don’t know with every 1 degree in intake air temp we lose horsepower and push our engines closer to detonation. If you can knock 10 degrees (Celsius remember) off the air temp how many horsepower is that worth. Think of the benefit on intercooled engines. You could be 10 degrees ahead in the cooling stakes if you set your engine bay up right.
I’M lucky my air-box is totally external to the engine bay and runs a forward facing inlet without any bodywork in front of it. A bell-mouth would no doubt improve its airflow and extract the last bit from the engine.
The test was on a stock LS400 (how convenient!) and showed that the temp difference between the ambient temp and the temp in the entrance to the over the radiator air intake to be 1degrees Celsius (all temps will be Celsius) when being driven and 3 degrees C when idling.
By comparison the under bonnet temp (where your average pod would draw) was 8 degrees hotter even when driving at 120kmh! When idling the temp rose to be 40 degrees hotter than ambient. The rate of rise was 3-4 degrees per second when idling.
When climbing a steep hill the under bonnet temp roe by 30 degrees. This all indicates a CAI will work wonders for your engine.
The test showed that under bonnet temps did not drop all that quickly when the car started moving. This tells us that a pod equipped car is sucking very hot air at the traffic light Grand Prix.
Further testing was done with a sensor inside the air-box. The temp was 4 degrees hotter in the air-box than at the inlet. This difference would rise to 12 degrees when the car stopped. The temp dropped quite quickly when the throttle was opened as cooler air entered the air-box. Conversely lifting off the throttle caused a rise in the air-box temp. Heat soak would no doubt keep the air warmer than it could be for quite a while. Does this mean if you have pre-ignition you shouldn’t back off as the inlet temp rises which will make it worse (lol).
The long and the short of this is it’s worth shielding your air-box and inlet pipes, throttle body and AFM from the heat of the engine bay in addition to feeding it the coldest air you can find if you want ultimate performance your engine can give.
Splitting hairs, being pedantic? I don’t know with every 1 degree in intake air temp we lose horsepower and push our engines closer to detonation. If you can knock 10 degrees (Celsius remember) off the air temp how many horsepower is that worth. Think of the benefit on intercooled engines. You could be 10 degrees ahead in the cooling stakes if you set your engine bay up right.
I’M lucky my air-box is totally external to the engine bay and runs a forward facing inlet without any bodywork in front of it. A bell-mouth would no doubt improve its airflow and extract the last bit from the engine.
