S/B rocker arm geometry and contact patch

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Kind of. I'll confess, I'm a bit tired and it's been a heavy schedule the last few days. I haven't been here (FABO) in like 3 days.

Speaking of which, back to the grind....gotta run.

Currently confused about raising or lowering the rocker arms.

Shim them up or mill the stands down? IDK, head hurts. Chow for now dudes.
 
The tip of the rocker is never any closer or further from the axis of rotation (center of the shaft). It's always exactly the same distance regarless of angle in relation to the shaft centerline. The problem I see here is the valve stem is tipped slightly in relation to that arc and the centerline of the shaft. So the exact point in space the tip and the stem touch can only be affected by the axis moving(the shaft, in this case would need to go deeper into the head) or the stem moving (again in this case, the stem being trimmed shorter). Because the stem is tall, the tip is touching it "early" in the trace of it's arc and simply rolling further out towards the exh side rather than crossing the center and coming back. This is why the heads that use long valves (W2/5/etc) have bolt in rocker shaft supports. Because they can be moved up or down as needed.
 
alright....
Rumble, get a real light spring, I've used stretched out spiral locks before, and put a feeler gauge between the valve face and seat 'lowering the valve like moper says' and see what happens to your wear pattern.
 
http://speedtalk.com/forum/viewtopic.php?f=1&t=20333&start=15

the whole thread will really give you some valuable info.

oh from the article...
in regards to rocker arm ratio throughout the lift cycle.
'try checking the rockers duration as follows It's really easy to measure.
First you zero the lash.
Then put an indicator on the lifter, and another on the retainer.
Rotate the cam to .010" lift on the lifter, and measure the lift at the retainer. Devide retainer lift by lifter lift.
Now move another .010" and repeat until you get to max lift.

For those of you that have never done this, you'll krap your pants when you see the results.'
 
I haven't read what you posted yet. I just had to put the engine in the bay because I need the garage space for a snap shot of the Magnum in the garage for classic insurance purposes. But, this is as far as I have gotten.......
Engine and tranny are in.
Intake runner height is to tall and needs to be milled.
P/S belt to short.
P/S pump interfears with Schumaucher (SP!) torque arm for the engine.
Need to order pushrods.
Find asprin.
Drink beer.
Remind wife that Butter Pecan ice cream rules, vanilla is just OK.

Other than that, the Dodge Magnum has been giving me trouble with the ignition. First the coil puked oil, then the ignition box dropped dead, then the distributor took a crap. Tools took a dump on me at a alarming rate as well. Timing light broke, a Sears engine analyzer w/tach broke, electronic tach broke, something else...er... to wound up right now to remember...actually, don't wanna remember. It's been a crazy week. I still have to get my Tux for the wedding.........ugh! LOL!

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Nice link 1w&cg. One poster there, "Panic" lives (relatively speaking) close to me. (Though an hours drive around here...........) I should speak with him. It may be productive if the K.I.S.S. method is used in this learning process.
 
rumblefish360 said:
Nice link 1w&cg. One poster there, "Panic" lives (relatively speaking) close to me. (Though an hours drive around here...........) I should speak with him. It may be productive if the K.I.S.S. method is used in this learning process.
Click to expand...

jones cams is on it too.

Which approach relies on app/$$$/ability thats for sure.

it was the most interesting thing I've read on the net in a while.
 
I love lurking in Advanced tech on Speedtalk. And the vast majority of posters are very good at explaining when you can't quite grasp something. Some very good info in that thread.
 
Gee I wonder if anyone ever came up with a solution for this here problem?:lol:
 
12many said:
Gee I wonder if anyone ever came up with a solution for this here problem?:lol:
Click to expand...

Not if anyone listened to how to fix a chev with tip alignment problems, "shorter pushrods" That only works on chevs and does the same thing as lowering the rocker posts on a Mopar, changing pushrod length on a Mopar will do ZERO for tip alignment/ sweep pattern FFS get a grip people.
 
WHo is the guy that has the kits/shims to correct misalignment?
 
It was a slow day, came across this among other topics. I find it interesting how things were back in the day....like reading old magazines! I look at it as a “how did we survive”.....another topic is back then how almost all cam recommendations posted were off the shelf. No posts about “custom grind” 24/7. How times have changed.
 
And another thing, you’ll notice in these old threads there wasn’t rampant likes, disagrees etc All that is pretty nonexistent . What archaic times
 
12many said:
It was a slow day, came across this among other topics. I find it interesting how things were back in the day....like reading old magazines! I look at it as a “how did we survive”.....another topic is back then how almost all cam recommendations posted were off the shelf. No posts about “custom grind” 24/7. How times have changed.
Click to expand...
Custom grind. :rofl: "I need a replacement cam for my 318" Call some obscure grinder for a magic bullet. !!! :lol:
 
There are a zillion threads here on “what cam” and if you start searching the forum from day one you notice they are all shelf cams being recommended. When did all the custom cam grinding become all the rage anyway? How did we survive!!!:eek: Just another interesting observation on a slow news day twiddling thumbs!:rolleyes:
 
12many said:
There are a zillion threads here on “what cam” and if you start searching the forum from day one you notice they are all shelf cams being recommended. When did all the custom cam grinding become all the rage anyway? How did we survive!!!:eek: Just another interesting observation on a slow news day twiddling thumbs!:rolleyes:
Click to expand...
I think the custom grinds became the answer when there was so much arguing about which shelf cam would be best. Not which one would work well but there seems to be a need to have the "best". They all work, some just work better. There's way too many variables. That's where the custom cam comes in. Give the variables to the grinder and have them pick one out that will work for your combination.
 
toolmanmike said:
I think the custom grinds became the answer when there was so much arguing about which shelf cam would be best. Not which one would work well but there seems to be a need to have the "best". They all work, some just work better. There's way too many variables. That's where the custom cam comes in. Give the variables to the grinder and have them pick one out that will work for your combination.
Click to expand...
Absolutely. Just interesting how things were not too long ago, and now it’s flip flopped. There’s a point here when that became so....the transformation. Likely with many new members joining. The new generation!
 
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