Bored out Cylinder .030 over

My cylinders were bored .030 over stock. Besides entering my new cylinder mass which I calculated to be 0.6766875 L how do I account for this change in my Main VE Table and MAF tables?

2003 GMC LM7

Compression Ratio (stock): 9.5:1

Cylinder Bore Stock: 3.780 in.

Cylinder Bore measured 3.810" (2/15/2023) .030 over-sized

Stroke: 3.622 in. (stock)

Engine Displacement: 5.32752 L (known stock) 5.3286 L (calculated stock)

Actual Displacement: 5.4135 L (calculated from measured bore)

Engine Displacement: 325.171080423947 cid (calculated stock)

Engine Displacement: 330.3530080724264 cid (calculated from measured bore)

Cylinder Mass: 0.6766875 L (calculated from measured bore)

TBH, I'd leave it as is as the rebore is ~1% increase in engine size, and the rest of the engine's breathing - intake and exhaust - will further negate the affect of the capacity change, so you're looking at rather less than the margins of error.

If this was a full-on race engine, where you were looking for fractions of horse-power, or lbs.ft or torque, it MIGHT be a different strory, but at your engine's level you're as likely to compromise it as improve it.

Have you made any other changes, other than the rebore, that might need to be accounted for?

Anthony,

I love that you're trying to do things the right way. If using HPT, under engine -> general -> cylinder volume, you update the per cylinder volume there.

No other changes are required based on the displacement change, and if nothing else was changed about the engine, MAF scaling and VE may not need adjusted.

That said, a fresh engine will operate a bit differently and shift as it breaks in. Also if you're rebuilding the engine, perhaps it was worn out prior, and those things can result in changes in engine VE.

While MAF scaling is meant to reflect air mass only, it's ultimately used to determine how much fuel mass is required to hit a target lambda value, so while the intake and MAF sensor hasn't changed, what the engine is doing with the air does change when VE changes, so some tweaking of MAF scaling may be required.

I wouldn't touch MAF or VE values before running the engine though, and I'd only tweak them if it turns out to be needed.

If on the other hand you changed heads, cam, valve job, compression, these are all things that can require big changes.