Dave,

The 1986 block you have should be the D9TE-AB block. The block casting number is casted on the outside of the block, behind the starter motor (if the starter is installed) and reads vertically.

If you have a D9TE-AB block, then I would say that is great for you since you intend to build a stroker motor. The D9TE-AB blocks have slightly longer cylinders, and the 557 strokers pull the pistons way down into the crankcase at BDC, so the block you have is favored by those building 4.5 stroker motors (they like the extra piston skirt support). Finally, if you are getting a chinese stroker kit, then the crank should already be the correct size to clear the tighter D9TE-AB crankcase, so again you are okay. But if you are stroking an oem Ford crank from an early engine, that crank will not fit the later block. If your block is standard bore, then opt for the .030" over pistons (not the .080"). the difference in displacement is negligible and you save a future bore for later use.

Incidentally, a 4.5 stroker will work in the earlier blocks too.

If you are building less than a 4.5 inch stroke motor, then either block is really the same.

There is a very slight possibility that you may have an E3TE casting block. If you do, then let me know.

If you have not yet bought your stroker kit, then let me know and I'll point you in the right direction/respectable stroker dealer.

The 4-bolt conversion for your engine requires that you do NOT use the 4-bolt conversion caps that are available from Milodon as their caps only fit the D0VE-A blocks. It would be best for you to go get the splayed caps from Engine Systems. Those will work well with the thin-web D9TE-AB block (as is all blocks except the D0VE-A).

Paul