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What should I do to my heads while blocks away?

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rang-a-stang View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rang-a-stang Quote  Post ReplyReply Direct Link To This Post Topic: What should I do to my heads while blocks away?
    Posted: Oct/19/2020 at 12:42pm
Going through my 401 again. Most details are here:

My 401 has a set of 3216090-1 heads. They have about 8k miles on them since they were last rebuilt. Their rebuild included:
Stainless exhaust valves, AMC factory intake valves, 5 angle valve job, Viton seals, Comp Cams springs, retainers, and keepers. Brass freeze plugs. I have ARP 7/16 studs, and Harland Sharpe 1.6 rockers. I port matched the exhaust ports to match a Remflex gasket, they look like this:


Intake ports were port matched to a FelPro intake valley pan. I did not get a picture of my heads' intake ports but here is my intake manifold port for reference:

Other than that, they are stock. I run an Edelbroke Performer intake (with EGR but EGR only runs when I have to pass CA smog), my cam is 224/224 on 110LSA, with .48" lift, hydraulic flat tappet, and long tube headers. I top it with a GM 454 Throttle body injection (about a 640CFM) and computer controlled ignition. The engine is apart for a new bottom end from debris making its way through my oil system. 

I do plan to clean my heads like crazy and (from another thread)
Originally posted by mixed up mixed up wrote:

...smooth out around the oil  return passages and look at the water passage in front for casting obstructing water flow 
I also plan to try to CC the combustion chambers but I will probably hit some snags and give up. 
Are there any other little tips and tricks I can do? I do not plan to disassemble them unless I "need" to but should I hit my intake and exhaust ports with a sanding drum and clean them up before final cleaning? Should I do anything to the combustion chambers? Or should I assume it ain't broke so don't fix it? 
79 Cherokee, 401
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PHAT69AMX View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote PHAT69AMX Quote  Post ReplyReply Direct Link To This Post Posted: Oct/19/2020 at 2:30pm
Stock type single valve springs?  Check installed height Spring Pressures, shim to equalize as needed?
Were the Spring seats and valve guide machined previously?
Had Lap the valves while the heads are off ?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rang-a-stang Quote  Post ReplyReply Direct Link To This Post Posted: Oct/20/2020 at 1:01pm
Originally posted by PHAT69AMX PHAT69AMX wrote:

Stock type single valve springs?  Check installed height Spring Pressures, shim to equalize as needed?
Were the Spring seats and valve guide machined previously?
Had Lap the valves while the heads are off ?
Yeah, stock type single valve springs from Comp Cams (they came with my cam kit, springs are part number 940-16). 

The machine shop that did my heads last time machined the spring seats so all the installed heights are equal. Valve guides were cleaned and measured to verify they were in tolerance. Valves were lapped when installed. I poured some mineral spirits in the combustion chambers to check the seal and it seems to be holding so I "assume" the seats are good? 

I was planning to use Easy-Off over cleaner to clean my combustion chambers. Is that a bad idea?
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Post Options Post Options   Thanks (1) Thanks(1)   Quote 6PakBee Quote  Post ReplyReply Direct Link To This Post Posted: Oct/20/2020 at 3:18pm
If the heads were reconditioned properly 8K miles ago, unless you are doing something that would  require different valves, springs, rockers, pushrods, OR you have identified a problem with the heads, why are you screwing with them at all??
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Post Options Post Options   Thanks (0) Thanks(0)   Quote WesternRed Quote  Post ReplyReply Direct Link To This Post Posted: Oct/20/2020 at 5:44pm
Cut loose with the die grinder, what could go wrong Wink
I've finally given up drinking for good...........now I only drink for evil.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote XJ6 Quote  Post ReplyReply Direct Link To This Post Posted: Oct/20/2020 at 6:10pm
Not quite understanding why only just the exhaust valves were replaced? If its me I'm not putting 40 year old 2 piece valves in a new engine even in a stock rebuild. I hate doing things twice so always try and complete the job right the first time. Pulling engines apart for repair after a complete rebuild has to be the most disappointing and time consuming thing we have all experienced. Grab a set of SI intake valves to complete your heads
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rang-a-stang Quote  Post ReplyReply Direct Link To This Post Posted: Oct/21/2020 at 12:05am
Originally posted by 6PakBee 6PakBee wrote:

If the heads were reconditioned properly 8K miles ago, unless you are doing something that would  require different valves, springs, rockers, pushrods, OR you have identified a problem with the heads, why are you screwing with them at all??
I have not identified any problems and as far as I can tell they were reconditioned properly. Your point is well made, though. I am asking more through ignorance; if there are any easy'ish or common sense fixes/upgrades I should do while the heads are off, that's more the type of info I am looking for. There very well may not be.  
Originally posted by WesternRed WesternRed wrote:

Cut loose with the die grinder, what could go wrong Wink
HAHA! Whelp, my engine is being rebuilt because I did not do a good job with my first rebuild and hosed up my bottom end. With that track record (0-1) I could easily ruin a good set of heads, too! Not saying I am not willing to grind a little but maybe not so much cutting loose...
Originally posted by XJ6 XJ6 wrote:

Not quite understanding why only just the exhaust valves were replaced? If its me I'm not putting 40 year old 2 piece valves in a new engine even in a stock rebuild. I hate doing things twice so always try and complete the job right the first time. Pulling engines apart for repair after a complete rebuild has to be the most disappointing and time consuming thing we have all experienced. Grab a set of SI intake valves to complete your heads
Machinist said the intake valves and seats were in great shape so he just did the "performance valve job" on them. The exhaust side was a bit worn so he recommended hardened seats and/OR stainless valves. I found these valves for much cheaper than the cost of the hardened seats so that's why I only replaced those. 
I will take your advice and look into some stainless intake valves. Every time I tell my bride I have to order more parts, I get a black eye and a new scar on somewhere on my head but sometimes you gotta do what you gotta do and if this is a common sense thing, maybe I take some blows to my melon. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote mbwicz Quote  Post ReplyReply Direct Link To This Post Posted: Oct/21/2020 at 4:50am
You need to have a serious conversation with your wife. Having a special car is different. 

Please ask her not to inflict bodily harm in visible areas of your body. People ask uncomfortable questions. 
1970 AMX. Holy Crap its easy to spend money on this car!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Boris Badanov Quote  Post ReplyReply Direct Link To This Post Posted: Oct/21/2020 at 4:52am
Unless it's broken don't fix it.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rang-a-stang Quote  Post ReplyReply Direct Link To This Post Posted: Oct/22/2020 at 11:30am
That's what it sounds like. Anyone see a problem with using Easy Off oven cleaner to clean the combustion chambers?
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