Berco BT6 Line Bore 7.4 454 Big Block Chevy

This shows the setup and machining of a Gen V 7.4. I over bored the diameter to 4.958 and used a special set of main bearings from King that has a .020 oversize OD to repair spun mains like this one had. I finished it up on the line hone.

[@ronflood5697]

I’d bolt the torque plate on and then check cylinder out of round.
As far as the mains, those King bearings are a great save.

[@jeeprenegade1985]

Probably just worn out-of-round .001", doesn't seem to be bad for a used engine. For a freshly machined bore, yes.

[@ronflood5697]

Removing the torque plate off a freshly honed bore that was round, could lead to it being out of round when relaxed. @@jeeprenegade1985

[@williamburch5333]

If I have spun bearings on vortec 8.1, can the factory size bearings still be put back in after the line boring process?

[@jeeprenegade1985]

I wouldn't think so, the cutter is making the radius in the block larger.

[@bradprok]

how does your engine block clamp into the machine . does it just connect to the 2 adjustable fixtues on each side the block or do you clamp it down to table also ? just curious ?

[@LakelandAutoMarine]

Yes and yes.

[@epskurt128]

Never run cutter outboard of support arms. .002" off-center is not good also

[@jeeprenegade1985]

Yeah, that's what it appeared to me as well, .002" off center, not .002" out-of-round. I would want the dial indicator reading the same at 12 and 6, and the dial indicator reading the same at 3 and 9. Any other readings in between, you can't do much about, they are most likely out-of-roundness.

[@waynekarjala2032]

Why are you making a video with all that racket in the background?

[@AshLongie]

Because he can 😂