Valve seals for camel hump heads?

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ChuckN

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Well @Ricko1966 not sure that the umbrella seals are going to be a good fit- passing them through the valve springs to check for clearance they seem to rub and hang up quite a bit. Seems like they’d get chewed up.

Turns out there were no seals at all on the exhaust, just the o-rings at the retainer.

But I think you were onto something about the springs being matched to the camshaft- or at least potentially. I found shims located on the springs seat. You could tell me I’m wrong (I’m wrong most times) but what I understand is that shims are used for aftermarket springs to achieve the correct seat pressure and installed height. Any input?
 

Ricko1966

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Sounds like you maybe best off taking your seals to a local machine shop and getting some matched up. See if they have some smaller umbrella seals to put on the exhaust. It's odd that the small diameter umbrella seals didn't fit. I guess it's different valve springs. Anyway what sent you down this rabbit hole in the first place? Never asked before but thought about it today. What is his original complaint. Nevermind I went and read post 1. Carry on.
 

squaredeal91

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Is it because they need to be installed and when pulled tight they will skinny up? Could you put one on and slide spring over it that way for a test?
 

bucket

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Well @Ricko1966 not sure that the umbrella seals are going to be a good fit- passing them through the valve springs to check for clearance they seem to rub and hang up quite a bit. Seems like they’d get chewed up.

Turns out there were no seals at all on the exhaust, just the o-rings at the retainer.

But I think you were onto something about the springs being matched to the camshaft- or at least potentially. I found shims located on the springs seat. You could tell me I’m wrong (I’m wrong most times) but what I understand is that shims are used for aftermarket springs to achieve the correct seat pressure and installed height. Any input?

That and also for use after a valve job. I'm guessing that a lot of places don't mess with it, but I've had sets done and they shimmed the stock springs for correct height and pressure after the valve job.
 

ChuckN

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Sounds like you maybe best off taking your seals to a local machine shop and getting some matched up. See if they have some smaller umbrella seals to put on the exhaust. It's odd that the small diameter umbrella seals didn't fit. I guess it's different valve springs. Anyway what sent you down this rabbit hole in the first place? Never asked before but thought about it today. What is his original complaint. Nevermind I went and read post 1. Carry on.
Yeah, definitely a rabbit hole. It’s a character flaw that I have. Once I get started on something I have a habit of doing that. And @squaredeal91 you’re probably onto something. There’s nothing lost but time at this point since I bought a nice Summit valve spring tool and can put them on and take them off at will.

All this hmmmming and hawing about the valve springs has gotten me nowhere. The truck is running fine, and I’m not racing it anyway. At least not at this point. What I need to do is tear it down this coming winter, pull the cam out and see what it is actually so I can make a decision from there and go forward with these older style heads with the appropriate springs or get an upgraded set of heads.

It’s going back together so I appreciate all of your patience!
 

Craig Nedrow

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That is what I would do Chad. Without that info, you are shootin in the dark. Cam/springs have three measurements and are important, seat pressure at a certain installed height, max opening pressure, at a certain lift, and coil bind. I took an old caliper, cut the bottom measuring face off, so that you can set it in the spring pocket, and the other end on the spring retainer to measure the height. At the shop, religiously checked each spring at the cam callout for height to check that the springs were close. A spring checker is set up with a stop at a certain height ex, 1.95, then each spring in checked to verify pressure, very fast. If all springs check out, then you check the seat to spring retainer, and then select the proper shims to meet that 1.95 installed height to get the correct spring height, and hence the correct installed pressure.
 

Ricko1966

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You don't need to pull the engine apart to verify cam,you can use a dial indicator,and a degree wheel to measure lift and duration. I'd measure lift at the pushrod with a dial indicator and timing tape on the balancer. Not dead nuts accurate,but close enough for qovernment work. Actually lift and duration would be accurate,but opening events would be skewed by the timing chain. Do this with the rocker removed.
 
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xm20k

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If looking for aftermarket heads. FloTek heads from summit is probably about the best bang for your buck if you're just keeping it a daily/cruiser and not building a race motor. They offer them in straight or angle plug as well as setup for roller or solids. They also offer them in 180 and 200cc versions in the same configs for a few bucks more.

I swapped a set of them (180cc) onto a spare 350 I rebuilt that had a set of camel humps on it that were junk and needed completely rebuilt. For the price of new everything resurfacing, valve job, machining the pockets for more lift and machining for threaded studs plus wait time, if they even passed Maga fluxing. I decided it wasn't worth messing with them.

 

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