I've got a mint B16 head that I plan on putting some stock size stainless steel valves into. Since the head is in great shape, is there anything I have to do to it when I replace the valves? I plan on replacing the valve seals, but what about the valve guides or valve seats? Is there any prep work to do to those parts to get them ready for new valves? Or can I just swap in the stainless valves and go?

 

You should have the valve seats touched up at a machine shop.

On Honda and most other imports, valve guide wear is non-existant.

I have a 89 B16A head and the guides and valves are within new spec. I also spoke to my machinist and he said he has never needed to replace guides on Hondas.

Just make sure your new valves are within new specs.

 

Thanks Rocket. Can a this "touching up" be botched by a domestic machine shop?

What exactly are they doing to the valve seats?

 

Valve seats can be out of round and pitted especially on the exhausts seats.

Seats are usually re-cut so the are concentric and have a even sealing surface. It's not that hard to do with a Serdi or Sunnen seat/guide machine.

 

Rocket is right about getting the seats done. I use to work at a machine shop. If you dont get the seats reground and you install new valves, the new valves wont seal good at all. Over the years, your valves wear into the seats. If you go put a new valve in a worn seat your not getting that tight seal.. You see what i mean...... any machine shop should be able to regrind the seats. Its a Really easily process. Probably around $80 labor depending on the shop.

 

Can you use used valves on recut seats? (assuming the used valves are still within spec)

 

Yes, just get them refaced.

 

Okay, last question. Is there any reason to put stainless valves on the intake side?

 

none really, since the intake valves will always be at a cooler temperature than the exhaust valves...

the intake valves are cooled by a mixture of the charge air and fuel...

hot spots occur on the exhaust side...
nothing to cool those valves down...

they take all the heat from the combustion and are constantly surrounded by 600+ Celsius temperatures.... hence burning a valve...