Yamato engine Temp

[Flatiron]

What is considered the optimum Cylinder head temp for a Yamato 302 on a CSH ?

[HydroKyle93R]

I think Guedo499 has some data on this. John?

[dholt]

keep it under 400 degrees...380-390 no problems.

at 3/4" height rule pumping water shouldn't be an issue anyway. But ream out the hole if you're on the edge of pumping water.

[Flatiron]

Thank you for the numbers Both my CSR and CSH are pumping water pretty decent, I'm rather inexperienced at reading plugs they seem a touch on the rich side. I just got a Temp gauge so I was curious about actual numbers. Thanks Again

[JohnsOldMercurySite]

good timing, would this be similar temps for the Y102? maiden run tomorrow