Re: what do i have?
Ford Motor Company has several different engine families of which the parts are not interchangeable between the different engine families. The Ford 428 is from the FE Engine family and the 429 is from the 385 Series engine family.
Big Block FE engines include the 352, 390, 410, 427, and 428 for example. The 385 Series engines include the 370, 429, and 460. Even if we determine which engine family is under the hood of your Mustang, I still cannot tell you what that exact displacement is.
The best way to determine if your engine is a 385 Series or an FE Series is by looking at the cylinder head casting numbers. They are located on the outside of the cylinder head, along the valve cover mounting rail and between the 3rd & 4th the exhaust ports. Tell us what the aphanumeric number is at that location and we'll go from there.
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