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Sorry if this is a stupid question first time doing my own engine build but I Just got a new set of profiler heads said valve seats have bin machined 5 angle job do I need to do anything like lapping to install the new valves into the heads ? new valves and brand new heads
Again sorry if this is a no brainer question lol
 

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Sorry if this is a stupid question first time doing my own engine build but I Just got a new set of profiler heads said valve seats have bin machined 5 angle job do I need to do anything like lapping to install the new valves into the heads ? new valves and brand new heads
Again sorry if this is a no brainer question lol
I would not recommend lapping the valves.
 

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Some feel the lapping compound gets embedded in the seat and valve and wears them faster. There are others that will chime in I am sure. I just use toothpaste to check the the seats and valves now.
 

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Some feel the lapping compound gets embedded in the seat and valve and wears them faster. There are others that will chime in I am sure. I just use toothpaste to check the the seats and valves now.
I was also told this buy one of the best cylinder head guys in the business.
I use a Sharpie marker to check seat contact... Works very well...
 

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Color the valve seat on the head, put the valve in the head, I use a drill, Chuck up on the valve stem, on low speed pull the valve against the seat with light to moderate pressure and spin it a little...
Check the seat to see the contact....
Brake clean the seat off then, do to same on the valve. Only Color one part at a time.
If you do seat and valve same time it tends to gum up some.... LOL
Works for me....
If they're off, get the seats and valve cut by a reputable shop with good equipment.
 

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Thank you. I recently lapped one valve on my head due to a bit of rust on the seat. The valve was closed, so I don't think any rust got onto the important spots, but lapped it just in case
 

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I was also told this buy one of the best cylinder head guys in the business.
I use a Sharpie marker to check seat contact... Works very well...
I do that also, works very well. I have one cylinder head performance builder that laps every valve. His theory is that the valves seat faster making more power sooner. I guess if one were to do an interference fit valve job it might be true, but that's not a performance valve job to me.
 

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I lap valves. I have had several heads come back after seasons in circle track and have never had an issue with lapping. Not saying it’s right but it sure shows you if something is wrong.

To the op I would lap in the valves because if the heads came with valve job from profiler in my experience 90% of them do not seal and guides are tight. Lapping will show you.
 

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I lap valves. I have had several heads come back after seasons in circle track and have never had an issue with lapping. Not saying it’s right but it sure shows you if something is wrong.

To the op I would lap in the valves because if the heads came with valve job from profiler in my experience 90% of them do not seal and guides are tight. Lapping will show you.
So will the Sharpie method.
 

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Please explain why not
Lapping will embed abrasive material in the valve and seat. I have never seen or heard of a higher end shop or cylinder head person(NASACAR, CFE, Ron's etc) that lapped valves in the last twenty years. If the seats are machined on good equipment by a competent machinist or even ground old school, there is no reason for them to be lapped. I f you doubt the quality of the work, check the seats with a run out gauge(Sunnen is good) or vacuum test them. If a seat fails the run out or vacuum test, it needs regrinding or recutting by a qualified person using proper equipment.
 

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They also CRN their valves and run on steel seats as do I .
Does that look like chrome? I have a set of fererra valves that I got with a set of heads with only dyno time on them, they look like chrome and can't even see any marks on the seat area. Called Ferrea with the part # but they weren't familiar with the chrome look.
 

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