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I think if you have the correct tools and the right information you can do anything. On the down side any small mistake can become very costly and or damaging to the motor.

I say bring it to a PRO who has a good reputation and does it day in and day out. If you need a number I can get you a guy who does excelent work (LA, California).
 

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I did it all by myself...I brought it to the machining shop, told them what to do, gave them the parts (that I bought myself!) and they did it!

...all by myself!
 

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There were things I did myself and there were parts I left to a machine shop. I had the machine shop check the head for flatness and plane it if necessary. I also had them seat the new valves properly. I did all the assembly, including installing and honing new valve guides (with the help of borrowed tools; this is not something to do with the wrong tools).
 

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Discussion Starter #6
Thanks for the info all! I really would like to start working on my own heads; having a 164 and a Spider.

Greg; I read through some things on your website over the weekend; really neat stuff you have done there! Thanks mucho for documenting all of the things you have done/do with Alfas. I have a few questions regarding valve work; maybe you or someone with your experience can comment on them.

I recently called a valve rework shop that specifically does Alfas; head work only (possibly some engine machining). I asked him about installing teflon seals; and his opinion was that viton seals were superior. His response was 'I don't know why you would want to put Teflon seals in; but I will if you want them'. While I understand that there may be 'professional opinion' on which type is best; could someone tell me why one would be preferred over another? Would re-work be needed sooner with the Teflon seal or vice-versa?

Is installing new valve seats required on each rebuild? Or just re-surface the valve seats? Is a multi-angle or radiused seat a performance modification (meaning much more costly); or should it be done regardless?

Would oversize exhaust valves be a good mild performance boost to the 3.0 V6 S-engine? Would increasing valve size on (intake or exhaust) potentially cause emissions problems with smog check or is change in performance only realized under hard accelerations?

If my engine has the cast-iron guides in the exhaust side is it necessary to change the valves to restore proper clearance? Should I plan on replacing all valves or only the exhaust side? Do new valves require grinding at the shop or just need to be lapped to the seat surface?

Do valve guides just need to be hand-reamed to size or do you need special honing tools to 'get it right'? Do you guys who rebuild your heads re-bush the oil pump and check clearances on the rocker assembly, etc and replace those bushings when needed; or is this something to not worry about? Would a good head rebuild shop be able to do the R/R of these areas or can I do it myself with the right tools?

I feel confident that I can do the various tasks of rebuilding the heads except for cutting the valve seats; if I can find the right tools to do the various tasks.

Thanks for any help/info you can provide...

-Russ
 

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Russ,
Regarding the valve seats, it depends on their condition whether they need replacing or just resurfacing. That's something I would have left to the machine shop if I needed to replace mine. Fortunately they only needed resurfacing to match the new valves.
If you're an AROC member, you might want to check with your chapter to see if they have a tool loan program and if so what tools they own. Sometimes whether you can/should do something vs. whether to leave it to the machine shop depends on whether you have access to the right tools. Hones for the valve guides are one of those things that you can do if you have the right sized hones, but the machine shop can do a lot quicker and easier.
 

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Larger valves and valve seats cut with multiple angles USUALLY improves performace, DEPENDING on cam timing and overlap, and many other factors such as headers, engine fuel/carb mapping and jetting, larger and/or higher compression pistons, and on and on...

Sometimes it can DECREASE performance if all factors involved are not coordinated.
 
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