Look what I found Mom!

[tanusfarms]

So As most of you may or not know the truck i recently bought seems to have nothing on it that is what should be there. My rear springs aren't stock, the bed isn't either, someone swapped cabs on it, the front axle strength doesn't match up with the quality of upgrades done of the rest of the rig, and the front bumper weighs almost 2/3 as much as my engine does!

Well i was out in the barn working on the truck some more when I thought just for fun I was going to check the stroke on my FE block that is in it. I figured it had a aftermarket carb and intake on it maybe someone played around with something more on it............and I do believe I was right. I removed the #1 plug and put the piston at the top of the stroke, inserted a wooden dowl and marked it, then proceeded to turn the motor manually till the piston was at the bottom of the stroke and marked it again, pulled the dowl out and put everything back the way it was. At this point i was really anxious to find out what I had so while trying to climb out of my engine compartment I almost face planted into the stack of hay bales on the other side of the barn (caught my foot on the freakishly large custom "tree pusher" [bumper]) after getting back on my feet i measured the marks, they sit 3.75" apart which tells me I have a 390. Am I correct or did I do this correctly? I just want to make sure it was done right, i mean if i should have fallen into the manure pile instead I'm sure I could con the wife into repeating the test after moving the truck.

no seriously did I do it right?

[hazelnut]

sounds right to me, you must have thought the truck had a 360 in it from your excitement.

[tanusfarms]

According to the frames vin number it was supposed to be a 360.

[68muscletruck]

sounds about right, 3.78 is the 390 stroke and with a wooden dowl you're bound to be a bit off vs using a depth micrometer etc... 3.5 is the 360/352 stroke, haha i had all the experience with this about two weeks ago when we pulled my '390' out for rebuild to find it was actually a 360... if you can't yank the motor, stick with the dowl method for now, but if you ever get the chance, pull the pan and check the casting # on the crank and match it up on the tech/tutorial on here to see

[averagef250]

Pretty good chance you got a 390 there. No need to yard it out to check for casting numbers on the crank. 360 cranks all have a notch cast in the rear flange to allow the rear throw to be drilled. 390 cranks lacked this notch. If you have to know for sure this notch is visible from under the truck with the inspection cover removed.