Right, the intake manifold is a double walled aluminum casting, cooled by the coolant. The thermocouple probe was inserted in a part that is not double walled near the entrance to the cylinder #5 (image above).
Avatar: XM757 in OK prepared for 1,000 mile trip home. Part of 6,000 mile journey in 2006.
1968 M49A2C modified with 1960 M756A2 truck bed and 1975 HIAB 765A knuckleboom. Heated dual tank system for biodiesel/veggie oil use.
1969 Ford XM757 8x8, 5-ton Pershing 1A truck tractor, the "improved" MV.
"Some things can't be made better, just differently......a lot of things actually"
All the multifuel engines have this intake manifold.
It's only cooling for high boost, doesn't do much for anything less than 6-7 psi after the engine warms up. It's not going to reduce the temp below engine op temp.
Avatar: XM757 in OK prepared for 1,000 mile trip home. Part of 6,000 mile journey in 2006.
1968 M49A2C modified with 1960 M756A2 truck bed and 1975 HIAB 765A knuckleboom. Heated dual tank system for biodiesel/veggie oil use.
1969 Ford XM757 8x8, 5-ton Pershing 1A truck tractor, the "improved" MV.
"Some things can't be made better, just differently......a lot of things actually"
This from knfilters.com : For maximum efficiency, diesel air filter restriction should be less than 25 inches of water vacuum, compared to a gas motor which uses only 10 inches of water restriction. Since diesels work harder at pulling air into the engine this creates a greater opportunity for dirt and silicates to enter the engine. Dirt or silicates in the engine can cause severe damage, including cylinder wall wear.
I measured 20 cm of water, which is 8 inches of water, so a new standard filter should be comparable to the K&N spec., unless I'm missing something here.
EDIT: The missing factor is the airflow. The K&N filter has a flow restriction of 4.3 inches of water (11 cm of water) at 350 CFM. We just need to figure the air flow for the multifuel engine under conditions reported above.
Avatar: XM757 in OK prepared for 1,000 mile trip home. Part of 6,000 mile journey in 2006.
1968 M49A2C modified with 1960 M756A2 truck bed and 1975 HIAB 765A knuckleboom. Heated dual tank system for biodiesel/veggie oil use.
1969 Ford XM757 8x8, 5-ton Pershing 1A truck tractor, the "improved" MV.
"Some things can't be made better, just differently......a lot of things actually"
The engine displacement is 478 cubic inches, which is 0.276 cubic feet.
For 2,000 rpm, the air flow is displacement x rpm divided by 2 = 276 CFM
During turbo boost there is the additional flow as a fraction of atmospheric pressure to add in, so for a boost of 6 psi, which is 41% of 14.7 psi (pressure at sea level). Adding 41% to 276 cfm gives us an an air flow of 389 CFM at 2,000 rpm.
For 2,500 rpm the flow is 345 CFM plus a boost of 11 psi (78%), which gives us 614 CFM.
So, the vacuum measurement above (previous posts) of 8 inches of water is for a flow of 614 CFM.
Avatar: XM757 in OK prepared for 1,000 mile trip home. Part of 6,000 mile journey in 2006.
1968 M49A2C modified with 1960 M756A2 truck bed and 1975 HIAB 765A knuckleboom. Heated dual tank system for biodiesel/veggie oil use.
1969 Ford XM757 8x8, 5-ton Pershing 1A truck tractor, the "improved" MV.
"Some things can't be made better, just differently......a lot of things actually"
Measuring the restriction of the air filter is a little tricky while driving, but I took the deuce to the store this morning and checked the numbers as I was driving.
According to this site, the comparisons are made at 350 CFM. http://home.usadatanet.net/~jbplock/ISO5011/SPICER.htm
Driving at 2,000 rpm with a turbo boost of 3 to 5 psi requires approx 360 FM of air. My vaccum gauge showed about 8 cm of water (3.2 inches of water).
Also at 2,000 rpm and about 1 psi of boost (315 CFM) gave me 5 cm (2 inches) of water on the gauge.
At 2,400 rpm and about 10 psi of boost gave me 15 cm (6 inches) of water. That's about 550 cfm.
The filter only has about 1,000 miles on it, so it's pretty clean.
Looks pretty good to me, but somebody else should make similar test runs for a more accurate picture.
Avatar: XM757 in OK prepared for 1,000 mile trip home. Part of 6,000 mile journey in 2006.
1968 M49A2C modified with 1960 M756A2 truck bed and 1975 HIAB 765A knuckleboom. Heated dual tank system for biodiesel/veggie oil use.
1969 Ford XM757 8x8, 5-ton Pershing 1A truck tractor, the "improved" MV.
"Some things can't be made better, just differently......a lot of things actually"
