Got results that I had not anticipate, fyi, Enjoy. WOODY
Lets take a trip and since I invited you, youll have to roll the way I go, so don’t get in my face about specifics as it is a thought experiment and close is good enough; buckle up and keep hands inside the moving vehicle.
Drive a srt with a dual inlet at about 60 steady, and have a 90 degree day, Iam going to say its about 2000 rpm which is 1000cyclinder filling per minute. A liter is about 61 cu. And the motor is 3.2 liters so in a minute were doing 1000 fillings at 3.2 liters times 61 or about
61,000 x 32. or about 195,000 cu. in. Per minute. Divide by 1728 cu. In. per cu ft. and you get 112 cu ft of air per minute.
Now the intake manifold pressure about 15 inches of Hg pressure or ½ atmospheric pressure in this example reduces the actual inlet air flow to about ½ of the 112 cu ft above. That’s 112/2 or 61 cu ft per minute going into the engine or 61cu ft /2 about 30 cu ft of air per minute / PER INLET pipe on the DCAI inlet system.
Ok so the engine is breathing about 30 cu ft of air per inlet per minute. The pipe is 3” in diameter or 1.5 squared, times pi: or 7 square inches of cross section. 30 cu ft of air are 30 x 1728 = 51840 cu in and divided by 7= 7405 inches of flow per minute or divide by 12 = 617 feet per minute. Now divide by 60 and you get an air speed in one of the DCAI tubes of about 10 feet per second or 5280 ft divided by 10 = 528 seconds per mile or 528 divide by 60 = about 9 miles per mile.
Thus the air flow in the inlet system is about 9 mph or 10 feet per second and the air going into the engine goes thru about 4 – 5 feet of pipe in about ½ second. The pipes temperature has ½ second to pick up heat during this time
AT full throttle your turning the engine 3 times as fast and breathing twice as deeply thus 6 times more air TIMES YOUR BOOST in BAR. So if your at 14.7 psi boost your intake is 6 x 2 or 12 times the air flow which reduces the time dwelling in the intake to 1/12 that of the 60 mph example above. 1/12 of ½ sec. is 1/24 of a second or about 0.04 seconds = 40 milliseconds.
What this did for me is to indicate that the inlet pipe heating is minimal during driving and next to nothing in wide-open throttle. The air cannot heat up enough to matter once you punch the throttle
As soon as you punch it the airflow picks up and there is minimal heating AND up to 15 times as much flow to scrub or cool the heat out of the inlet piping. Before the math analysis, I though there was more on the table to be had in this insulation of the inlet
So we have arrived back at reality and Ill work on foam mylar insulation on my inlet for what it is worth. FYI just to let you know I measured my INSULATED inlet pipe to be at 140 degrees at 60 mph cursing on a 90 degree day - THIS IS NOT THE AIR FLOW AS I DID NOT PUT THE PROBE INSIDE THE PIPE FOR THIS TEST SEQUENCE. Nother day.
ENJOY, W
DY