06/17/2026
Classic truck.
Modern 5.3 power.
Holley EFI to control it all.
This 1972 K20 came in LS swapped with Holley EFI and ready for a proper custom dyno tune. But before tuning could even begin, we found an issue with an O2 sensor that had to be corrected first.
And that’s the thing with swaps — details matter.
Bad sensor data = bad tuning.
And bad tuning = bad drivability.
So before making power, we made sure the foundation was right.
Once the O2 issue was resolved:
Holley EFI calibration was dialed in
Cold starts cleaned up
Idle stabilized
Throttle response sharpened
Power delivery smoothed out
Now this old K20 has modern power and modern drivability to match.
Only thing left?
It could definitely use some modern brakes to keep up with that 5.3 power. 😎
At Lsxkilr Custom Calibrations, we don’t just tune them — we make sure they’re ready to be tuned.
👉 Visit https://lsxkilrcustomcalibrations.com
Check pricing and schedule your custom dyno tune.
Old truck.
Modern power.
Done right. 🔥