I built a LQ4 that I got for free. It needed a complete rebuild has it has two seized rod bearings. I rebuilt with basically all new parts/bearings. I used a BTR Stage 1 truck cam kit, 863 4.8/5.3 cylinder head with the valve springs that came with the cam kit. It should be 10.7-1 compression. I saw that similar builds using the same head/bottom end made 470+ on an engine dyno. Its in an 82 square body K20. Mated to a SM465, 1 ton axles and 4.56 gear. 39" tires. It previously had a 5.3 LM7 which ran great.
It ran and drove great with the 5.3. Now with the new motor installed, after driving it loses almost all power and I noticed it is pulling all out of the timing. Fuel trims are under 10% and coolant temps are under 210. I have started with deleting all the automatic transmission dtc's and need to go road test. It is still on the 5.3 LM7 tune. I am new to HPtuners and don't know where to start. So far I bumped up the idle as it was sometimes struggling in the 5-600rpm range. Any help would be appreciatedKeeblereditog53.hpt