440 bore size

[willyd61]

I recently received a 440 block that was sonic tested and bored to .060 over. The cylinders actually measure closer to 4.378 instead of 4.380. My concern is that 060 over pistons might be too tight, and 055 pistons may be too sloppy. I'm not crazy about the idea of spending more for machine work. It seems like quite a bit to hone out. Hoping you engine guys can shed some light.

[JonH]

Not sure what you mean by "recently received", but a block should only be finish bored and honed when the machinist has the pistons in hand. They will fit each piston to a bore based on the pistons diameter. Forged or cast, tolerances are different. Buy .060 over pistons and take the block to a good machinist for finishing.

[Skid Row]

I recently received a 440 block that was sonic tested and bored to .060 over. The cylinders actually measure closer to 4.378 instead of 4.380. My concern is that 060 over pistons might be too tight, and 055 pistons may be too sloppy. I'm not crazy about the idea of spending more for machine work. It seems like quite a bit to hone out. Hoping you engine guys can shed some light.

If I recall my  440 was bored .60 over with the final 3 thou. with torque plates....?

[willyd61]

JonH,
I guess bought would be the better word. From a reputable guy.

[willyd61]

I recently received a 440 block that was sonic tested and bored to .060 over. The cylinders actually measure closer to 4.378

I recently received a 440 block that was sonic tested and bored to .060 over. The cylinders actually measure closer to 4.378 instead of 4.380. My concern is that 060 over pistons might be too tight, and 055 pistons may be too sloppy. I'm not crazy about the idea of spending more for machine work. It seems like quite a bit to hone out. Hoping you engine guys can shed some light.

If I recall my  440 was bored .60 over with the final 3 thou. with torque plates....?

That's probably what it is. I was trying to cut my costs, but honing with a torque plate is probably the best bet.

[screamindriver]

 Piston type and even ring type will dictate what the final finish hone will be...You got exactly what you needed{ and what I would want} with the block... As stated you'll need to send the parts off for the final hone...

[willyd61]

Piston type and even ring type will dictate what the final finish hone will be...You got exactly what you needed{ and what I would want} with the block... As stated you'll need to send the parts off for the final hone...

Sounds good. I'll get ahold of the machine shop and go from there. Thanks.