hardened valve seat installation
hardened valve seat installation
(OP)
Contacted a local motorsport machine shop today to ask if they could install a set of hardened exhaust valve seats in my cosworth BDA aluminium cylinder head.
They said they could do it but there was no guarantee for the seats staying in place afterwards...
When i queried them as to why the factory seats don't fall out of their recess i was told because they are done right and nobody has the equipment/technology in the aftermarket to do it like the factory...
Has anyone heard of anything like this and could someone explain the 'right' procedure that would be employed to install the seats so they stay in place??
Regards
Kal
They said they could do it but there was no guarantee for the seats staying in place afterwards...
When i queried them as to why the factory seats don't fall out of their recess i was told because they are done right and nobody has the equipment/technology in the aftermarket to do it like the factory...
Has anyone heard of anything like this and could someone explain the 'right' procedure that would be employed to install the seats so they stay in place??
Regards
Kal





RE: hardened valve seat installation
http://www.delwestusa.com/
RE: hardened valve seat installation
Regards
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RE: hardened valve seat installation
RE: hardened valve seat installation
RE: hardened valve seat installation
Thanks for the input guys.
I'll just add something i found while doing some research which is the variance you find in technique and tolerances used by various engine builders for seat removal/refitting.
One will say you only need .001 inch interfernce while another will say .006 another will say they stake the seats for safety while the other will say if you're staking the seats then you're not doing the job right in the first place and the list goes on.
Problem is who should we trust...?
RE: hardened valve seat installation
thousands, but seats need to be tighter, around .006. As someone said, the condition of the counterbore is important.
It is common to put the seat in deep enough to enable a small
amount of aluminum to be rolled over the seat, just to be sure.
RE: hardened valve seat installation
Take the time to learn the proper procedure and then oversee the installation. If the machine shop objects to having you observe...find another shop. I learned my lesson as I have had shoddy work done by some pretty big name racing shops, BTDT!
Rod
RE: hardened valve seat installation
RE: hardened valve seat installation