CM870 ECM AND TURBO PROBLEMS

[Rawze]

(12-26-2024 )1693rattler Wrote:  ... the liner protrusion was double checked before the head went on ...

Its an old block ... Heat stresses, heat cycling, and relief over time at the mid-stops needs to be compensated for by raising liners above factory levels ...

if you did not raise the liners to 0.014" or higher (max 0.016") ... and only left them at 0.010" - 0.011" after shims, couter-bore, etc... , then it will only live about 3-4 years and have head gasket issues, unless you turn it down to the 1750-trq range (or lower) so that it does not let go again. This is a mistake that just about everyone rebuilding them does these days, and then wonders why it did not hold together as long as it should have.

the link I posted above has all the info (not found in the manuals) needed to make it last another full million miles again ... at 1850+ trq (minus any abuse) ... everything said in that post is important.

so ... if you had them set back at ... 0.010" - 0.011" ... then have the programming turned down to 485HP, 1750trq .. and be thankful you found this info, and curse yourself out for not doing more research, instead of cursing that engine out in another 3-4 years due to having to dump another $$20k+ in it again. Do not say you were not warned.