Volvo #1000531 heads

What mods need to be done to a 531 head previously used in a boat, for automotive use? I am aware that it most likely will not have the sodium filled exhaust valves needed for Turbo use. But besides that and the combustion chamber volume difference compared to the 1000530 head, what other mods are necessary (I believe the head has to have a hole drilled and tapped to accept a fuel injection system, coolant temperature sensor below intake port #3 ...manifold mating surface flange).
Is there enough material around the exhaust valve seats, to accept slightly larger exhaust valves? Would larger valves hit the tops of the cylinder bore?

Wrong area

We installed larger valves no problems

shane5.2vodoo said:

What mods need to be done to a 531 head previously used in a boat, for automotive use?

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depends..Budget, corrosion, funny insert in no4 utbl?s

I am aware that it most likely will not have the sodium filled exhaust valves needed for Turbo use.

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That was Volvo being all Lutheran and full of deep guilt.. so despite the cars being very low power and barely stressed, they used the old 1940s technology and shoved in natrium kyllda valves. HOWEVER Millions of higher powered, hotter running car have driven trillions of miles without sodium filled valves.
Get decent SS vales, give them a decent seat and have fun. I suggest 38mm

But besides that and the combustion chamber volume difference compared to the 1000530 head, what other mods are necessary (I believe the head has to have a hole drilled and tapped to accept a fuel injection system, coolant temperature sensor below intake port #3 ...manifold mating surface flange).

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That is simply set a 531 and whatever you have side by side and compare.

Is there enough material around the exhaust valve seats, to accept slightly larger exhaust valves? Would larger valves hit the tops of the cylinder bore?

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38mm is safe on stock seats and is a good size..
Valve are inline with bore..Head is over 12mm deep plus a min gasket thickness of about 1mm means even with big lift rally cams the valves are nowhere near the pistons.

Sodium filled exhaust valves are NOT needed for a turbo car. They will dissipate heat better but it's not a necessity.

Also as far as I'm concerned you would not need to modify the head to accept fuel injectors since the injectors are placed in the intake manifold and not the cylinder head.

Natrium valves are just internet hype...not needed in real life. Neither are any holes for FI needed unless you're going with Kjets and stock look. #3 cylinder sensor plug tapped is probably needed, however, unless you're more comfortable with having a T-pipe somewhere in your hoses.

You might get lucky and find one of the later 80's AQ125 engines where the #4 port is the same shape as all the rest, and the sensor holes are already tapped.