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Is this the same with stamped steel rockers? it's easy to draw a center line on a roller rocker, but I think on a stamped steel rocker it may be a little harder.
Its not easy with a comp pro magnum, either.
My teeny tiny bee hive spring retainers also make it work nothing like in the Straub video, too...
Is this the same with stamped steel rockers? it's easy to draw a center line on a roller rocker, but I think on a stamped steel rocker it may be a little harder.
No, it's Not the same. Stamped rockers are Far more forgiving. for example, look at most OE LS motors' rockers ... have a nice robust bearing in trunnion but still has a "slider" tip.
Most timing sprockets have 2 degree changes. The ground in 4 degrees is for chain stretch modern quality chains you would take the 4 out
I heard that the built-in advance is largely because most consumers buy cams that are too big and then end up with crappy idles and vacuum and fuel economy and then blame the cam company for a "bad cam".
Mike Jones said to install it straight up; I don't think he does the "grind in more advance" thing...
Derek, you're evil like that trying to convince me to spend even MORE money on tools I'll only use once, but that price is OH SO TEMPTING... and I WOULD love to be able to confirm total valve movement and duration at different lifts...
I heard that the built-in advance is largely because most consumers buy cams that are too big and then end up with crappy idles and vacuum and fuel economy and then blame the cam company for a "bad cam".
Mike Jones said to install it straight up; I don't think he does the "grind in more advance" thing...
Adam
Adam just think about it for a second. I just pulled out an old cam card to see what the valve event numbers were for a 232/238 @ .050 cam were. Intake opens at 9 degrees to .050 inches before Before Top Dead Center. When installed straight up. Now advance the cam 4 more degrees. Because your piston is still on the way up you have some pumping effect which will cause reversion in the intake tract and the associated lumpy idle.
I finally get home and feel like I've figured out how to measure my pushrod length so I can order pushrods and move on with getting this engine done: I decided to put checker springs on both the intake AND the exhaust on Cylinder #1 and of course the exhaust valve gives me trouble and won't come off with the spring fully compressed (on rare ocassions the valve needs a smack from the under side to pop-loose the lock: unbolt the stupid head, take it off the block no big deal.
Then when I get ready to put the thing back on I look at the top of my pushrod checker tool and realize it's got weird scrape marks, then I realize it's bent to hell.... NO IDEA why this happened, but now I get to wait until next weekend to get a new checker tool, then check lengths, THEN order pushrods and THEN hopefully continue without paying more stupid tax. -3 weeks out now on making progress. UGGGGGH!
I wish I had someone local I could just pay to come measure the @#@#$@# pushrod length.
Adam
Last edited by NewbVetteGuy; 04-13-2019 at 12:26 PM.
Put it in a vise and straighten it out. As long as the threaded part still works ok, it'll be fine. All you're looking for at the end of the game is the overall length anyway.
As long as the end-to-end length is the same no matter which way the checker is laying, it will make zero difference.
Put it in a vise and straighten it out. As long as the threaded part still works ok, it'll be fine. All you're looking for at the end of the game is the overall length anyway.
As long as the end-to-end length is the same no matter which way the checker is laying, it will make zero difference.
the end of the pushrod checker is messed up too. I have an amazon warehouse 6 miles from my home. They said they can have a new one here by 8:00pm tonight.
crash course
Find nearby 1/4 - 4/10 mile circletrack & 1/8 mile strip ... get out there and into pits-sidelines ... don't drink at track & keep your eyes-ears-wits open ... humble & endear yourself to local crews ... volunteer to push cars, carry tires, wipe down-clean cars etc (don't know much but I'm willin' to learn, help whatever y'all might need) ... build another set of relationships ... there're some folk who might help you avoid paying too much tax. Likely more crew ops around CT than strip.
Derek, you're evil like that trying to convince me to spend even MORE money on tools I'll only use once, but that price is OH SO TEMPTING... and I WOULD love to be able to confirm total valve movement and duration at different lifts...
Adam
Having a dial indicator and a magnetic base can be handy in a number of instances. Looking for runout on a brake rotor/pulley/wheel is just a small list of things you could do with one. Checking backlash on a ring and pinion also. It’s one of those tools that once you have you’ll find a use for.
Ok, all, practical questions now:
My Comp Cams pushrod length checker got here a bit early so I've been playing aroudn with getting geometry and pushrod length correct.
-On my exhaust valve of cylinder #1 I just played around with permanent marker and dry-erase marker and just getting the geometry right by guessing, checking witness marks, and adjusting the adjustable pushrod and the nut on top of the rocker.
-On the intake I wanted to do it "by the book" using the Straub 90 degree angle method here's my summary of my understanding of the procedure and what I did just so hopefully someone can double-check me:
"Showing my work" on thinking and what I'm working with:
Given the outside shape on the Comp Ultra Pro Magnum rockers, it's pretty hard to make a straight edge between the center of the rocker trunion and the roller tip bearing, so I took two little strong earth magnets and attached a straight edge to the rocker trunion and just adjusted it until the bottom was pointing straight between the centers of both bearings. (No question, more comment on this part.)
I have 7/16" rocker studs so there are 20 threads per inch which means each turn of the nut is 0.05" vertically.
My cam with my 1.6 ratio rockers has a max lift of 0.600" on the intake and 0.576" for exhaust; just going off the intake, I need 1/2 that distance or 0.300" (0.288" for exhaust)
I had my short-travel hydraulic roller lifters soaking upright in engine oil for the past 2 weeks or so so I pulled one out and installed the pair in cylinder #1
I had checker springs installed on both the intake and exhaust valves for cylinder #1
I had silly putty over my piston valve reliefs towards the intake side
My head was set on the studs with 5 nuts just lightly snugged up (no gasket(My gasket is the Felpro Shim 0.015" thick gasket)
Procedure:
Cover the tip of the intake valve with permanent marker and dry erase over the top
Adjust the height of the rocker on the rocker stud until the straight line drawn through the center of the rocker trunion and the roller tip bearing is parallel to the top of the valve retainer (this is pretty scary high up on the stud)
Adjust the rocker 1/2 of my cam lift down on the stud (0.300" for the intake; @ 0.05" per turn with my 7/16" studs == exactly 6 turns of the adjustment nut. (This will make the line drawn between the trunion center and roller tip bearing center parallel to the head at 1/2 of my valve lift.) -Lock the adjustment nut
Elongate the comp adjustable pushrod length checker until it starts getting tight then stop.
Rotate the engine over 3 times with my crank socket and check the witness marks.
Questions:
Am I going to need different length pushrods for the intake/exhaust because of the lift difference between the two? (It seems to be a pretty small difference)
Can I just add 0.015" length to my pushrods to make up for my compressed head gasket thickness? (I could also back the adjustment nut off 3 turns which should be 0.015" and then just go with the ACTUAL pushrod length)
How do I measure the adjustable pushrod's length assuming I don't have a micrometer that goes this big? -There's got to be a calculation for how much distance each turn of the pushrod checker == right?
How tight do I make the adjustable pushrod length checker before I stop and measure? -Do I do the normal pre-load procedure that I would do if I were using REAL pushrods? (the extra 1/4 or 1/8th turn or whatever?)
Is there a good way to know whether I actually collapsed my hydraulic roller lifters and completely invalidated all my measurements? -If so, what?
Assumptions
With checking springs and "taking it easy" on pressure, rolling the engine over three times should not collapse my short-travel, slow-leakdown hydraulic roller lifters
Adam
Last edited by NewbVetteGuy; 04-14-2019 at 09:33 PM.
Adam, your getting way too deep into this. The Straub/Foxwell method is based of mathematical calculations so you shouldn't need to spin the engine over.
1. Make a 90 degree template from a piece of plastic and 'eye ball it'
2. checker springs should be so light that a lifter never collapses
3. Pushrod lengths are 'approximate. Unless you get lucky on length or choose to order custom, anything off the shelf will be rounded up or down.
4. Checker tool is too tight if the valve moves Use a ruler.
Why mark the valve? If you follow the Straub/Foxwell method and get perfect geometry and yet the marks are off centered what are you going to do? Change the geometry? What if the marks are perfect and yet the geometry offs? Now what? Pick a method, perfect geometry or perfect marks and go with it.
Question # 2. How do I measure the adj pushrod checker length?
Once I had mine set perfectly, I wrapped some electrical tape around the joint so it couldn't move. Then took it to a machine shop for length verification with a very large micrometer.
Question #2B There has to be a calculation for the number of turns on the tool in reference to the length. Nope, sorry. Too many variables there for any accuracy using a formula.
And last. For those of you not using weak "checking valve springs" to establish pushrod length, Summit sells just one solid lifter for $3. It will not collapse and give false readings when turning the engine over by hand. It sure comes in handy for just such occasions of checking valve-stem wear patterns.
Adam, your getting way too deep into this. The Straub/Foxwell method is based of mathematical calculations so you shouldn't need to spin the engine over.
1. Make a 90 degree template from a piece of plastic and 'eye ball it'
2. checker springs should be so light that a lifter never collapses
3. Pushrod lengths are 'approximate. Unless you get lucky on length or choose to order custom, anything off the shelf will be rounded up or down.
4. Checker tool is too tight if the valve moves Use a ruler.
Why mark the valve? If you follow the Straub/Foxwell method and get perfect geometry and yet the marks are off centered what are you going to do? Change the geometry? What if the marks are perfect and yet the geometry offs? Now what? Pick a method, perfect geometry or perfect marks and go with it.
Thanks Jim.
I figured that might be confusing. Just to clarify: I did the "Witness marks" method first just to try it out and experiment with it for my own learning. I like the Straub / Foxwell method and am actually using that, I was just using the witness marks as a 2nd validation that I did it right. (If the marks are way off then, my assumption is that I did something wrong and I need to revisit the method.)
I still am unsure about the items, below although I can certainly use "Head's UP"'s method of measuring the final pushrod length as I DO have a local machine shop that I've been working with and they're only a 30 min drive away; they'd probably do this for me.
Questions:
Am I going to need different length pushrods for the intake/exhaust because of the lift difference between the two? (It seems to be a pretty small difference)
Can I just add 0.015" length to my pushrods to make up for my compressed head gasket thickness? (I could also back the adjustment nut off 3 turns which should be 0.015" and then just go with the ACTUAL pushrod length)
How do I measure the adjustable pushrod's length assuming I don't have a micrometer that goes this big? -There's got to be a calculation for how much distance each turn of the pushrod checker == right?
How tight do I make the adjustable pushrod length checker before I stop and measure? -Do I do the normal pre-load procedure that I would do if I were using REAL pushrods? (the extra 1/4 or 1/8th turn or whatever?)
Is there a good way to know whether I actually collapsed my hydraulic roller lifters and completely invalidated all my measurements? -If so, what? -For the responses that say "just buy a solid roller from Summit" -how do I know that Summit's solid roller is the same height as my particular hydraulic roller?
Am I going to need different length pushrods for the intake/exhaust because of the lift difference between the two? (It seems to be a pretty small difference)
Can I just add 0.015" length to my pushrods to make up for my compressed head gasket thickness? (I could also back the adjustment nut off 3 turns which should be 0.015" and then just go with the ACTUAL pushrod length)
How do I measure the adjustable pushrod's length assuming I don't have a micrometer that goes this big? -There's got to be a calculation for how much distance each turn of the pushrod checker == right?
How tight do I make the adjustable pushrod length checker before I stop and measure? -Do I do the normal pre-load procedure that I would do if I were using REAL pushrods? (the extra 1/4 or 1/8th turn or whatever?)
Is there a good way to know whether I actually collapsed my hydraulic roller lifters and completely invalidated all my measurements? -If so, what? -For the responses that say "just buy a solid roller from Summit" -how do I know that Summit's solid roller is the same height as my particular hydraulic roller?
Adam
1. Probably not. The difference in lift is split by 2 so whatever it is it isn't much
2. As mentioned earlier just shim the heads with whatever. Baseball cards whatever.....
3. With a tape measure. Off the shelf push rods are in .100 or .050 length. You'll be rounding up or down. .05" = 1.27mm. Any tape measure can measure this....
4. Until the slack is gone
5. Measure them then add subtract the difference. You should be able to look up your lifter height and order a solid match.
04-09-2019, 08:31 AM
