Q: what happens if you add a lead substitute to an engine that run premium unleaded?

asked by on September 01, 2017

By adding the lead substitute and its catalytic safe, is there an upside or downside? The engine needs a valve job. Would that prolong the use of the engine without a valve job or am I just throwing my money away?

My car has 86000 miles.
My car has a manual transmission.

You should not add any lead replacements in this engine since the pistons and valve train is designed to not use it or need it. Lead was used to cool and lubricate the valves in older engines from the 60 and 70’s. You may harm your O2 sensors and catalyst over time with the lead additive.

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