I have a stock 390 bored 30 over. with stock 390 4bbl flat top pistions. I have been told that the 428 crank will work with this, but then have been told the stock rods will work. Then told the stock rods won't work or just some rods will work. This is a 1969 engine with all stock parts, but the cam and timing chain are not. What will work? Here is the real question. If I have two cars, both with 390s rebuilt stock, but one has the 428 crank. will you be able to tell which car has the 428 crank. Is it worth the time and money for the switch?

 

Mercury did this from the factory and called it the 410.

You can check the flywheel through the inspection cover and look for a weight on one side but other than that you won't know.

390 rods and 428 rods are 100% identical. 428CJ rods had bigger bolts.

In order to make the 390/428 crank swap you will need new pistons. The later model 390s used 410 pistons. You will be at about 10.5:1 compression if you use these though unless you open up the combustion chamber.

The 428 crank will add a great deal of torque to your build. The only drawback is that getting a 428 crank is expensive unless you get lucky and find one.

Also keep in mind that the 410/428 were externally balanced at the flywheel and the 390 was internally balanced. You will have to have a weight attached to your 390 flywheel and have everything balanced.

 

It is worth the time for sure. I have been using one to haul around my 71 f250 4x4 for a while now and its a good motor. i actually just rebuilt mine with a Comp Cams XE274 cam, edelbrock RPM, 1407 750cfm carb and my 390 heads are off galaxie 500 with some light port work and this motor runs strong. i run a 4sp, 4.10s and 35's and its a good setup. Good sounding motor too

 

Thank you all for the info on the 428 crank. I just rebuilt this 390 a year ago and it has less than 3000 mile on it. It was stated that I should use 410 pistions. The pistions in the motor are new 30 over 390s flat top 4bbl. Due to the cost of the crank and other work, I would like to keep the cost down. Can I just use these 390 pistions and still get more power. This is in a 1964 Galaxie with C6 auto shift kit and ford 9inch pos 370 gears. She will already bark the tires on the 1-2 upshift with 1/4 of the pedal down.
Thank You
Martin.

 

Regular flat top pistons will come up above the deck with a 428 crank. The 410 pistons actaully set down in the bore when they used them on the late 390.

When selecting a piston you want a piston that comes to the top of the bore and then adjust your compression with a dome piston or a dish piston. This allows for better quench and efficiency. It also reduces the likelyhood for detonation at a given compression ratio.