Recessed valves

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73beast

73beast

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I have a set of 360 heads where three of the exhaust valves have sunken 1/8-1/4 inch into the seats (past flush with the combustion chamber). suprisingly it was still running good. is there any way of fixing this? or should i scrap the heads...?
 
I wasn't getting the impression these heads had much options for seat inserts. Any suggestion on where to find the part for that? I'm not finding much online. Summit has a replacement ex seat, but that's not enough for what im looking at, right?
 
That is a "machine shop only" operation. tmm
 
A good head guy will have the seats and be able to install them for you.

If you can't find one locally, I have a good guy in Detroit that I can give you his number.
 
You'll probably find the edges of the valves worn razor sharp too.
Another set of later model heads might be the best route money wise.
Good luck
 
My suggestion would be to scrap the heads and either find another set of heads or if your budget will allow it, get some aftermarket aluminum heads. There is also a good chance that you will find the heads "might" have the beginnings of some cracks around the sunken valves. Having 8 hardened exhaust seats and new valves put in can get a bit pricey, whereas some of the aftermarket heads will be about the same price ready to bolt on. Just my .02
 
Most of the time when the guides are worn as well as valves sunk, it requires going to the next size larger valve/hard seat. so if th shop can press a slightly larger seat into the head and keep the same diameter valve, ur lucky....otherwise u'll need to step up to both larger valve and seat insert.
 
If the valves have recessed, you'll need new seats installed. Any competent machine shop should be able to do this, it's a standard operation. You also need new guides, and probably new valves. In other words, you need a complete head rebuild. The heads you have now should be OK as cores, they just need everything.

What is your budget? You'll have several hundred into these heads, and new heads can be had for only a few hundred more. Or perhaps you can find a set of used heads that can be run as-is for a few hundred less.
 
By the time you have new seats put in, new guides, some or all new valves, etc etc. You'll have $800 in these heads.
 
My guy charges 15 a seat installed, 150 for a complete V8 valve job and that is including bronze or iron guides installed and a skin cut on the deck, So your looking at 280 EZ for getting your old 360 heads back to stock. Might as well go big with new stainless valves for another 100 and have him open the intake to 2.02 if that is what your looking for for probably no additional charge. You can get later model useable 360 heads with hardened seats already there (induction hardened, not inserts) for less from a few guys in here.
 
Thank you all for the input. It sounds like im getting steered towords replacing the heads. I'm trying to keep a low budget on this motor, so ill be looking for a good price on used. Will need to machine the spring seats from stock for the dual springs im using. im thinking the heavy springs may have helped sink the valves, but they are what compcams recommended for my xe284 cam.
 
I can have my local machine shop rebuild the heads with hard seats,guides,valve job, mill..etc.. for $350, new valves is an extra 80-100 bucks.

Where in the heck are some of you taking ur heads for a rebuild?
high end race shop, evernham motorsports or something? lol
 
what/where is your local shop? theres two shops i go to around here, and i'll check to see what they'd charge, but if you can get a better price somewhere within driving distance i would rather go with that.
 
As pishta said, I had similar prices when my 383 heads were redone ($10 per hardened seat in yr 2000). They also fixed a few cracks by drilling and welding in plugs. I recall ~$150 for 2 heads. They returned with the valves and springs installed. That was a big rebuild shop near the Atlanta airport, forgot the name.

If me, I might take the opportunity to upgrade to aluminum heads to save weight. But, I read that most or all require changes to the rocker arms, push-rods, and valves, so maybe not so easy and more $$$.
 
It's a 318 with 360 heads, comp cams xe284 cam .507/.510 240/[email protected] edel rpm airgap intake headers. The compression ratio was a bit of a mystery. that's why I took the heads off, to cc them calculate what its at and machine them to make 10/1. But I can't get a accurate cc reading with the sunken valves. So fixing that is my first step
 
CC the sunken valve itself.lol then subtract that once the chamber is filled.

or cc the chamber without the sunken valve, the sunken valve is probably worth 2cc, maybe
 
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