Top end work
 

Hi everyone,

‘’I know there are endless threads for 700/525 head work but I couldn’t find much on the machining required to redo the top ends

if anyone can help on what is required on the surfacing, lapping etc and if I can do it at my local machine shop. He does a lot of work for Chevy and Ford engines and seems to be confident he can do these.

I’ve been told that the heads are quite challenging to machine and there is a certain process behind the ones on these motors and it differs quite a lot from your typical Chevy big block heads.

appreciate the help

I can't think of anything special that would be different than a conventional head. I might learn something too.

…special process?

I’ve never done one of your heads but I’ve done more heads than I can count.
first find a good shop you can trust. Don’t let a guy work on your stuff that you think isn’t being honest or fair. My experience is mainly good with shops and they have treated me very well when I treat them with respect ask about how and why they do things and what they would recommend. Most of these guys love LOVE their work. If he doesn’t, you don’t want his work.

minimal work:
get them decked, have the seats checked (replaced), have valve stem seals replaced, valves cleaned and polished if not being replaced.
I normally take my heads in completely stripped (no locking retainers, springs, or valves it saves a few bucks on the bill and speeds up turnaround).
I’ll strip the heads and use oven cleaner and purple power with a pressure wash to get gunk off. My local shop can’t use a powerful cleaner anymore (not sure on your rugs) so the cleaner I bring them the better they turn out.

ask how they do valve jobs. I’ve had very good results doing it by hand with the suction cup and grinding compound, but boy is it some work. Most shops won’t do it this way anymore due to labor hours or charge a high per hour price. A good guy can do ok with a drill… not my preference. Machined is best but pricey vs doing it by hand yourself.

have your heads ported If you want more power. Ask about his porting theory and practice. Does he cnc or do by hand?
Does he raise, smooth, and gasket match exhaust ports
Does he lower, smooth and gasket match intake ports
Does he smooth out combustion chamber and how? What happens (who repairs/replaces the head) if he hits a water passage?
What about valve seats? Some guys cut those back to about 85-86%. You don’t want to drop a valve seat…I’ve heard of guys cutting those way back.
I prefer a slight trim on the seats for flow but most work done on the intake ramps, combustion chamber, and exhaust ramps for flow.

upgrade your valve springs, retainers, and valves if it works for your application.