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One Comment and One Question on Compression
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One Comment and One Question on Compression
Ive been driving the truck a lot lately (74 F100 Shortbed Styleside) FE360.. This thing gets such bad gas mileage I thought someone was steeling gas from me... Ok now the question, What should the compression be per cylinder on this truck?
JRB65
JRB65
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Drivers Side 120, 120, 120, 115
Passenger Side 120, 120, 120, 115
Its a 1974 FE360 BB and I dont know the history on any rebuilds so I dont know if these are good numbers or not. I did read somewhere that you want the difference between the Cylinders to not be more than 10% total from high to low. If I just knew the actual number Im supposed to be reading???? Is 120PSI what I should be getting on this engine???
Thanks,
JRB65
Passenger Side 120, 120, 120, 115
Its a 1974 FE360 BB and I dont know the history on any rebuilds so I dont know if these are good numbers or not. I did read somewhere that you want the difference between the Cylinders to not be more than 10% total from high to low. If I just knew the actual number Im supposed to be reading???? Is 120PSI what I should be getting on this engine???
Thanks,
JRB65
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From: Stanley, VA
The compression is okay. Usually Ford didn't specify an exact figure because of all the variables, in particular, cranking speed. What Ford did specify was that the high and low cylinders be within, IIRC, 20% of each other.
Yours, with a high to low of 5 lbs. (4.16%) is well within the specs. Your compression is fine.
Yours, with a high to low of 5 lbs. (4.16%) is well within the specs. Your compression is fine.
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The compression is okay. Usually Ford didn't specify an exact figure because of all the variables, in particular, cranking speed. What Ford did specify was that the high and low cylinders be within, IIRC, 20% of each other.
Yours, with a high to low of 5 lbs. (4.16%) is well within the specs. Your compression is fine.
Yours, with a high to low of 5 lbs. (4.16%) is well within the specs. Your compression is fine.
I kinda figured the way this thing is running that it must be pretty good, No smoke out the back and all the plugs had a light brown apperance. For a 40 year old engine this thing is pretty tight. I did find a list of compressions for a 390 and they were all around 130 to 140PSI and I had heard the 360 was a low compression engine so I figured 120 was probably good. Anyways thanks again,
JRB65
Just on a side note im getting ready to start working on my 1950 ****** 4X4 Pickup and Im putting a 1948 Flathead Ford V8 in it. Ive always wanted to build one of these old Flatheads. It should be a lot of fun to put together..
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From: Near Yosemite CA
Good numbers, as with 360/390's the rear two seem like they are always lower, I would check your timing, do a tune-up, plugs/wires/cap rotor, points if applicable and adjust your carb with a vacuum gauge. You didn't state, but what is your trans and rear end ratio?
With all my trucks I have and have had, they had a happy spot, most of the older ones are in the 55-60 range, they ain't happy goin fast! And as I told Chanman when he bought "Ed" my 73 SCS, "welcome to life in the slow lane!"
With all my trucks I have and have had, they had a happy spot, most of the older ones are in the 55-60 range, they ain't happy goin fast! And as I told Chanman when he bought "Ed" my 73 SCS, "welcome to life in the slow lane!"
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Good numbers, as with 360/390's the rear two seem like they are always lower, I would check your timing, do a tune-up, plugs/wires/cap rotor, points if applicable and adjust your carb with a vacuum gauge. You didn't state, but what is your trans and rear end ratio?
With all my trucks I have and have had, they had a happy spot, most of the older ones are in the 55-60 range, they ain't happy goin fast! And as I told Chanman when he bought "Ed" my 73 SCS, "welcome to life in the slow lane!"
With all my trucks I have and have had, they had a happy spot, most of the older ones are in the 55-60 range, they ain't happy goin fast! And as I told Chanman when he bought "Ed" my 73 SCS, "welcome to life in the slow lane!"
It has a C6 and a Ford 9 with 3.20/1 gears. It runs down the road at 60 to 70 pretty nice but if you get much above that it tends to run a lot of RPM's. 60 is about 2200 and 70 is about 2500. It seems like you dont have to get these engines really wound up to make a lot of torque. Pulls hills really nice.
JRB65
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Lead Driver
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From: Near Yosemite CA
Pickupmanx2,
It has a C6 and a Ford 9 with 3.20/1 gears. It runs down the road at 60 to 70 pretty nice but if you get much above that it tends to run a lot of RPM's. 60 is about 2200 and 70 is about 2500. It seems like you dont have to get these engines really wound up to make a lot of torque. Pulls hills really nice.
JRB65
It has a C6 and a Ford 9 with 3.20/1 gears. It runs down the road at 60 to 70 pretty nice but if you get much above that it tends to run a lot of RPM's. 60 is about 2200 and 70 is about 2500. It seems like you dont have to get these engines really wound up to make a lot of torque. Pulls hills really nice.
JRB65
3.20 should be good, what kind of mileage are you getting? My 73 SCS had 390 and 3.73's got around 10 up here, maybe 12-13 in the flats.
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Need to go on a little trip to chech that, but I would guess 10-12 range but not sure. Im going across town today so maybe I will check it.
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Yep the Vacuum advance is hooked up, but what I need to do is hook up the timing light and have My Son rev it up to 2000 and see if its actually working. I would guess the way its accelerating that it is.
JRB65
JRB65
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