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I got a call from a member who found a 'project' engine. He was enthusiastic about this find for $1,000 because the owner simply lost interest in the project:
Completely magnafluxed and machined 390 block, bored +.030",
Heads are re-done
all the parts are there, etc, etc.
I asked about the pistons, and he said that was the only part missing.
I told him to run away from this 'deal' as fast and far as possible.
A good engine machine shop must have the pistons to measure FIRST, before the cylinders are bored and honed. Piston-to-bore tolerances cannot be attained unless the pistons are there.
That's why most engine machine shops order the parts, because as soon as they arrive, boring and honing can start.
At the factory, 'blank' aluminum pistons are machined to size. From the same machine, Ford puts these 'finished' pistons in a constant temperature room for 8 hours before 'air gauging' them. Again from the same cutting machine, four different sizes come out and are sent to four silos marked, magenta, blue, yellow, white. When Production Control arrives in the morning, they look at the fullest silo, and inform the block dept. to brush all the cylinders to, 'blue pistons', for example.
I suspect the reason this owner stopped his project is because someone screwed it up and he doesn't want to invest any more money in machining costs. Since the cylinders are supposedly bored thirty over, they probably need to be rebored and sized to new +.040" pistons.
I told him to keep searching for an old, tired 390 that is still together. That ensures all the parts are there including the bolts. Look for something caked in dirty oil with a little rust thrown in. Cleanup is 90% of every restoration, so expect that. The gold is underneath. - Dave
Completely magnafluxed and machined 390 block, bored +.030",
Heads are re-done
all the parts are there, etc, etc.
I asked about the pistons, and he said that was the only part missing.
I told him to run away from this 'deal' as fast and far as possible.
A good engine machine shop must have the pistons to measure FIRST, before the cylinders are bored and honed. Piston-to-bore tolerances cannot be attained unless the pistons are there.
That's why most engine machine shops order the parts, because as soon as they arrive, boring and honing can start.
At the factory, 'blank' aluminum pistons are machined to size. From the same machine, Ford puts these 'finished' pistons in a constant temperature room for 8 hours before 'air gauging' them. Again from the same cutting machine, four different sizes come out and are sent to four silos marked, magenta, blue, yellow, white. When Production Control arrives in the morning, they look at the fullest silo, and inform the block dept. to brush all the cylinders to, 'blue pistons', for example.
I suspect the reason this owner stopped his project is because someone screwed it up and he doesn't want to invest any more money in machining costs. Since the cylinders are supposedly bored thirty over, they probably need to be rebored and sized to new +.040" pistons.
I told him to keep searching for an old, tired 390 that is still together. That ensures all the parts are there including the bolts. Look for something caked in dirty oil with a little rust thrown in. Cleanup is 90% of every restoration, so expect that. The gold is underneath. - Dave
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