diffrent cranks

i was going to slowly by parts to rebuild my engine next fall/winter. and i have the 4.6 in my truck and i wanted to go with the 5.4 for the added torque and wanted to know if a 5.4 crank will fit in a 4.6 block. i know the bore is the same size but didnt know if they used diffrent blocks.
thanks doods

 

To my understanding they are virtually the same engines other than the bore....someone can chime in if the know anything else.....

 

i know that the bore is the same and the stroke iis more on the 5.4

 

Different Strokes:

The 5.4L with the same bore as the 4.6L will have a longer stroke. That implies changes in pistons, rods or deck height. If the pistons and rods interchange, then the deck must be higher than the 4.6L to accomodate the longer stroke....so what you propose won't work. (For a fact the deck for the 5.4L is 29mm higher than the 4.6L and engine parts interchangeability from year to year is almost non-existent......Chevy small-blocks these engines ain't!!)

Go here for all the particulars: http://en.wikipedia.org/wiki/Ford_Modular_engine

 

Makes since ^^^

 

ok thanks. so i will need a 5.4 block out of the junk yard. is there anything else to watch out for in doing this

 

Sort Things Out Carefully:

Yes, try to keep the various components within a model year; or check carefully for component compatibility from one model year to another.