Thread: Did I buy a 428 and get a 390 Thunderbird?

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Hey, get yourself a 6" dial caliper, whether you have to steal, beg, buy or borrow one. Have someone to bring any piston to top dead center by putting a socket and ratchet on the bolt at the front of the crankshaft that holds the harmonic damper onto the crank. You can stand by a cylinder and keep checking that you are close to TDC on that cylinder by checking with the depth function of your caliper. It probably will never come to zero, because the manufacturer of the piston will have made if to that it will not come to the deck of the block at zero, but make it come as far to the block as possible. When you have TDC, record the reading on your dial caliper from the top of the deck to the top of the piston. It may be 0.020", 0.025", o.030" or whatever. Now, have your helper turn the crank to move the piston to bottom dead center. Move it around a little to be sure you are at BDC. Record that measurement from the top of the block to the top of the piston. From that figure, deduct the figure that you had with the piston at top dead center. For a 390, the stroke will be 3.780", for a 428 it will be 3.980". Good luck and sorry about your hair and nails.

Hey guys, how did I do. I clicked those figures off without referring to anything.