Changing a cylinder head
Changing a cylinder head
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Discussion

vrsmxtb

Original Poster:

2,003 posts

180 months

Wednesday 21st September 2011
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How interchangeable are cylinder heads, specifically on Mazda MX5 1.8 DOHC units? Would an engine block be happy with a different head on it, I'm wondering if any different wear tolerances etc could cause issues?

MrF1xa

15 posts

175 months

Wednesday 21st September 2011
quotequote all
Do you mean just swapping the cylinder head for one off another identical engine? If so no problem in principle- it's common practive to source a secondhand head from scrappy to replace one which is cracked or otherwise damaged. You'd need to check the new one for straightness of the gasket face and I would be surprised if it didn't need a skim, so make sure that after the skim it is still within tolerance. I would also, as a minimum, remove all valves, check seats and guides for wear and relap. Remember to fit new head bolts as well as new gaskets as pretty sure they are stretch bolts on these?