White smoke and now motor is locked up

[olddog]

Originally Posted by Rick Parker

Ernie may be on to something. Many of you with the Big inch Fe's rightly use aftermarket heads made of aluminum. They will by nature move around a little because of aluminums expansion properties. That being said, it's possible that after several heat cycles, the clamping load is diminished, allowing the gasket to be forced towards the intake port by the pressure exerterted on the gasket by the pressurized coolant.

Not to mention 13 or so psi of manifold vacuum pulling on the gasket.

Aluminum thermal expansion is about 4 times that of cast iron. No doubt it is a factor, but maybe not the biggest factor. If it was all to thermal expansion, all iron would be best, aluminum intake only a little worse, intake and head worse yet, and an all aluminum engine much worse by leaps and bounds.

We all know to bolt torque plates on, and torque down the mains before honing to get true bores. I've read that setting the block on the mounts and torque up the bell housing is done by racers looking for the last Hp. So, blocks do flex. So much so that girdles are sold.

Now when a FE is thumping out 500 plus ft lb of torque, the tranny (drive shaft actually) is trying to rip the motor mounts from the frame. I have to question if the flexing of the block is more movement and stress on the intake gasket than the thermal expansion. The intake is likely helping the block to keep from splitting in two.

Thoughts?