Do both these engines share the same crankshaft?
5.4/5.8 crank
- Thread starter 1raresnake
- Start date
Yes
Sounds good. Thanks man.
you can interchange them but the are not the exact same crankshaft.
They are interchangeable, but, if I'm not mistaken, the 5.8 is stroked to 5.8L. So you will need either taller pistons or longer rods, if you plan on using a 5.8 crank in a 5.4; the reverse if you're going the other way. Somebody correct me, if I'm wrong.
Stroke is 4.2 on both the 5.8 and 5.4 only difference is bore of 3.6 vs 3.7
"How to achieve the extra 400cc displacement over the 5.4 must not have taken long, either. The 5.4 V-8 is already physically constrained in stroke, both inside the crankcase and outside, as a physical package that must fit a Mustang engine compartment. In the crankcase, the careful juggling act of stroke, piston height, rod length, and crankshaft counterweight clearance is already pretty well played out in the 5.4. Lengthening the stroke would quickly crash the pistons and crankshaft counterweights, leaving the other stroke-increasing option of raising the deck height. But raising the deck height on a V engine means making the engine both taller and wider, an impossibility given the Mustang's engine-bay dimensions.
If a longer stroke was out, then a bore increase was not without issues, either. As detailed in our Coyote and RoadRunner articles, Ford's multimillion-dollar investment in V-8 machining centers is not flexible when it comes to changing bore centers, and the modular engine family is thus fixed at 100mm bore centers. So, the SVT engineers couldn't stretch the 5.4's cylinders farther apart. Nor could they move over to the bigger architecture of the 6.2 V-8 as found in the SVT Raptor. That engine is too large for the Mustang engine compartment, plus it would be prohibitively expensive to design a better breathing Four-Valve cylinder head for it, as well.
That left increasing the 5.4's bore, an option open thanks to the recent maturation of spray-bore technology. This is a technique Ford has invested in for years and quietly debuted in the 2011 Shelby's aluminum block."
From this ARTICLE
Users who are viewing this thread
