Pistons and Crank for 4.3L Stroker Build


New Member
Hey guys,

Just bought my 04 mustang 3.9L and started working on it. Currently have a BBK CAI and PaceSetter H Pipe Dual exhaust conversion with flowmaster 44's on. Right now I'm trying to plan out how I'm going to stroke and bore my block out to go to 4.3L. I want to keep this on the cheaper side if possible, and I will be doing all the work myself with help from my step-dad. I know I can get a crank out of a F150, but which year would work with my block? I know there is a difference between the internal and external balance on some of the years. For pistons, I was thinking these https://www.summitracing.com/int/parts/uem-3152hc-75mm/overview/ . Will they work? If not, how do I figure out what will? I would like to punch the cylinder 30 over while I'm doing the build , because why not? lol. Ive heard the rods for the 351W will work for this build, so right now thats what I'm planning on using

Let me know your guys thoughts, any input is appreciated


Active Member
All 4.2 cranks were internally balanced, so it doesn't matter which year. Those pistons are fine for a cheap build. 351W rods are too short, and have pin bores that are .006"-.007" too big for those pistons. The '96-up 3.8, 3.9, and 4.2 all used the same connecting rods. Just get the pistons and crankshaft, and you'll be in business with your old rods.