Superelbert
Norwegian wood
Just thought I'd share some recent experience here..
I'm running a Megasquirt EFI system on the 318 in my '71 Dart, whic I'm now in the process of re-tuning after improving the cooling with a new rad and electric fans and ugrade from narrow-band to wide-band Lambda sensor.
After driving some and getting the engine properly warmed up, I started getting porblems with Idle stability and engine re start.
My intake iar temperature sensor, mounted in the intake opening of the air filter box, showed a temperature of up to 70 degrees C. (!)
I did a quick chek with my IR thermometer, and sure enough the surface temperature on stuff in that area was in deed that hot. I don't think the intake air was that hot, I attruibute part of the reading to sensor heat soak.
I figured my problems was part due to lean out from the EFI calculating wrong air density from too high temperature reading, but the low density of the hot air could allso be a factor.
A buddy had some intake air hose left over, and I installed this, drawing air from underneath the car just below the battery, installing the intake air sensor about 7 inches from the hose intake side.
Now the temperature doesn't get above 45 degrees C.
Wether you run carb or EFI, this example clearly shows the impact of underbonnet temperature and the importance of drawing your fresh air from the right place.
In my case, addressing this was a key to getting the EFI to function properly and the engine to run well, but a 25 degree C drop in intake air temperature allso means better efficiency and more power!
This problem really only came to my attention after I installed an electric fan, the old mechanical fan which was running all the time obviously served to keep the under bonnet temperature down.
I'm running a Megasquirt EFI system on the 318 in my '71 Dart, whic I'm now in the process of re-tuning after improving the cooling with a new rad and electric fans and ugrade from narrow-band to wide-band Lambda sensor.
After driving some and getting the engine properly warmed up, I started getting porblems with Idle stability and engine re start.
My intake iar temperature sensor, mounted in the intake opening of the air filter box, showed a temperature of up to 70 degrees C. (!)
I did a quick chek with my IR thermometer, and sure enough the surface temperature on stuff in that area was in deed that hot. I don't think the intake air was that hot, I attruibute part of the reading to sensor heat soak.
I figured my problems was part due to lean out from the EFI calculating wrong air density from too high temperature reading, but the low density of the hot air could allso be a factor.
A buddy had some intake air hose left over, and I installed this, drawing air from underneath the car just below the battery, installing the intake air sensor about 7 inches from the hose intake side.
Now the temperature doesn't get above 45 degrees C.
Wether you run carb or EFI, this example clearly shows the impact of underbonnet temperature and the importance of drawing your fresh air from the right place.
In my case, addressing this was a key to getting the EFI to function properly and the engine to run well, but a 25 degree C drop in intake air temperature allso means better efficiency and more power!
This problem really only came to my attention after I installed an electric fan, the old mechanical fan which was running all the time obviously served to keep the under bonnet temperature down.
