My 347ci build
07-26-2013, 09:35 PM
#162
Chuck and Rezin' hope you guys are cool with me razzing you. Your brand of OCD helps us all make better builds and definitely makes for some interesting reading. Its fun to watch MEs go crazy. Im an EE, I dont even line up the vice on my mill. Hell,I chucked a mill bit in a hand drill and "counter-bored" some holes today at work lol.
Rezin, I dont know, but if you arent an engineer you missed a calling..LOL. Your thread is awesome.
Rezin, I dont know, but if you arent an engineer you missed a calling..LOL. Your thread is awesome.
07-27-2013, 08:54 AM
#163
TECH Fanatic
07-27-2013, 01:23 PM
#165
Chuck and Rezin' hope you guys are cool with me razzing you. Your brand of OCD helps us all make better builds and definitely makes for some interesting reading. Its fun to watch MEs go crazy. Im an EE, I dont even line up the vice on my mill. Hell,I chucked a mill bit in a hand drill and "counter-bored" some holes today at work lol.
Rezin, I dont know, but if you arent an engineer you missed a calling..LOL. Your thread is awesome.
Rezin, I dont know, but if you arent an engineer you missed a calling..LOL. Your thread is awesome.
And agreed, Rezin's thread is awesome. Reading his motivated me to try and be as thorough with my build.
Originally Posted by ds98formula
This build is sick great attention to detail. How long tell its done
07-27-2013, 09:53 PM
#166
finished the oil pick up tube today/tonight
started by cutting the new screen retainer plate out and drilling some holes. step drills kick so much *** on sheet metal
then removed the coarse screen
oem screen laid in
Semi-finished retainer plate laid on top
Clamped it up with vice grips and stretched the edges to wrap around the head of the pick up tube with a hammer
Welded up. I opted to weld on the backside for several reasons - 1) to keep heat away from the mesh to keep from blowing through it, and 2) there was already a lot of metal there from the previous welding that was done - more metal = more thermal capacity = less chance of blowing through on thin metal. actually welded up much more easily than I thought it would, though I'm sure keeping it cool helped. I had compressed air handy and would blow it off after a small section was completed.
Ported the pump-side of the tube to get rid of the ledge created by the ID of the pipe where it met the flange. The transition is more seamless now - you no longer feel a "bump" running your finger over it.
Also stoned the mating surface flat. It must have warped slightly from the heat when they welded it on - in the above picture you can see the low spots on it
Ready to go
started by cutting the new screen retainer plate out and drilling some holes. step drills kick so much *** on sheet metal
then removed the coarse screen
oem screen laid in
Semi-finished retainer plate laid on top
Clamped it up with vice grips and stretched the edges to wrap around the head of the pick up tube with a hammer
Welded up. I opted to weld on the backside for several reasons - 1) to keep heat away from the mesh to keep from blowing through it, and 2) there was already a lot of metal there from the previous welding that was done - more metal = more thermal capacity = less chance of blowing through on thin metal. actually welded up much more easily than I thought it would, though I'm sure keeping it cool helped. I had compressed air handy and would blow it off after a small section was completed.
Ported the pump-side of the tube to get rid of the ledge created by the ID of the pipe where it met the flange. The transition is more seamless now - you no longer feel a "bump" running your finger over it.
Also stoned the mating surface flat. It must have warped slightly from the heat when they welded it on - in the above picture you can see the low spots on it
Ready to go
Last edited by ckpitt55; 07-27-2013 at 10:08 PM.
07-28-2013, 09:36 AM
#168
Post 167;pic #2;I simply can NOT believe that you didn't port/radius/smooth
the inside of that tube which was cut by a pipe cutter and now the ID @ the
opening is 0.0027635% smaller than the rest of the tube's inner diameter !!!
What a restriction that I just don't know how you could sleep on it......
Just kidding with ya man....GREAT build....
the inside of that tube which was cut by a pipe cutter and now the ID @ the
opening is 0.0027635% smaller than the rest of the tube's inner diameter !!!
What a restriction that I just don't know how you could sleep on it......
Just kidding with ya man....GREAT build....
07-28-2013, 11:42 AM
#169
Originally Posted by RezinTexas
That looks really good, great mod for sure.
Post 167;pic #2;I simply can NOT believe that you didn't port/radius/smooth
the inside of that tube which was cut by a pipe cutter and now the ID @ the
opening is 0.0027635% smaller than the rest of the tube's inner diameter !!!
What a restriction that I just don't know how you could sleep on it......
Just kidding with ya man....GREAT build....
the inside of that tube which was cut by a pipe cutter and now the ID @ the
opening is 0.0027635% smaller than the rest of the tube's inner diameter !!!
What a restriction that I just don't know how you could sleep on it......
Just kidding with ya man....GREAT build....
I'll be the first to admit that I will likely see no measurable improvement from doing that but figured it wouldn't hurt...had the tools and the time so why not. More of a "fit and finish" thing than anything else.
08-10-2013, 01:41 AM
#171
Winding down to the last couple things here. Just a heads up: I'll be geekin out a little more than usual in this post.
I've spent the past couple days here researching pushrods and how best to measure for the correct length. I think I've settled on a double taper 3/8"-5/16" rod from trend after reading this thread here: http://forums.corvetteforum.com/1572507024-post1.html (a great read if you have the time).
cliffs: stiffer than 11/32, but lighter than a full 3/8". basically the stiffest you can get without machining the heads for more clearance.
As far as measuring goes, I wasn't happy using the comp tool and counting turns to determine the gauge length required - with each turn being 0.050" and my desired preload being 0.025 - 0.030", it wouldn't take much for me to be wildly off on my guesstimate - and that's all counting turns is - a guess. The equivalent of using plastigauge to determine bearing clearances.
After searching for a while, I came to a solution I think is much more accurate. I bought a set of mitutoyo calibrated 8" calipers from mcmaster and picked up a pair of #6 washers. Gauge length is defined to be the point on the rod where the tip measures 0.140" in diameter - it is not the tip-tip length of the rod, but somewhat shorter. Using gauge length instead of overall length removes the "clipping" of length that the oil passage causes from the equation. #6 washers have a .140" ID (check them), so theoretically by sandwiching the checker tool in between these two washers I'd get the gauge length in my calipers by subtracting the washer thickness from the overall measurement. Here's a visual of what I'm talking about:
Trying to hold the washers and checker while measuring was a pain in the ***, so I just glued the washers to the jaws of my calipers temporarily using 3M photomount spray adhesive. Enough to hold it, but easily removable when I'm done.
My procedure went something like this:
1) Install pushrod checker and rotate engine until you're on base circle. Did this by feel because I didn't have the degree wheel installed. It's easy enough to observe.
2) Expand checker until rockers have next to no play in them when snugged down, but not to the point where they can't move at all and/or feel tight.
3) Remove rockers, remove checker tool and tape it up to prevent it from spinning. Reinstall and verify that nothing moved.
4) Remove and measure with calipers.
5) Reinstall checker again to verify that nothing moved during handling - ideally you get the same feel at the rocker that you did when you initially pulled it for measurement.
Using this method, my desired pushrod (gauge length) is the total measurement on the calipers - the washer thickness + my desired lifter preload.
for example: 7.741 - 0.060 + 0.030
I'm just about there, but want to compensate for the inaccuracy of the calipers as well. This tool is calibrated, but it still has an accuracy limited to +/- 0.002" + .0001*L (i.e. the longer your measurement the more uncertainty is attached to it). For example - I measured a 2" calibration standard and found that the calipers were reading 0.002" short. I'm going to use a 7" and 8" mic standard to determine how far off it is in my measurement range that I'm interested in. With those two error values, I'll be able to interpolate in between the two depending on what my checker measurement is and compensate accordingly.
More to come on this but wanted to post it up since it's fresh in my mind at the moment. In short, of the 8 lengths I've measured for so far, only 2 came out identical and there was as much as 0.050" variation between my required lengths. Pretty eye opening.....this is why you measure.
I've spent the past couple days here researching pushrods and how best to measure for the correct length. I think I've settled on a double taper 3/8"-5/16" rod from trend after reading this thread here: http://forums.corvetteforum.com/1572507024-post1.html (a great read if you have the time).
cliffs: stiffer than 11/32, but lighter than a full 3/8". basically the stiffest you can get without machining the heads for more clearance.
As far as measuring goes, I wasn't happy using the comp tool and counting turns to determine the gauge length required - with each turn being 0.050" and my desired preload being 0.025 - 0.030", it wouldn't take much for me to be wildly off on my guesstimate - and that's all counting turns is - a guess. The equivalent of using plastigauge to determine bearing clearances.
After searching for a while, I came to a solution I think is much more accurate. I bought a set of mitutoyo calibrated 8" calipers from mcmaster and picked up a pair of #6 washers. Gauge length is defined to be the point on the rod where the tip measures 0.140" in diameter - it is not the tip-tip length of the rod, but somewhat shorter. Using gauge length instead of overall length removes the "clipping" of length that the oil passage causes from the equation. #6 washers have a .140" ID (check them), so theoretically by sandwiching the checker tool in between these two washers I'd get the gauge length in my calipers by subtracting the washer thickness from the overall measurement. Here's a visual of what I'm talking about:
Trying to hold the washers and checker while measuring was a pain in the ***, so I just glued the washers to the jaws of my calipers temporarily using 3M photomount spray adhesive. Enough to hold it, but easily removable when I'm done.
My procedure went something like this:
1) Install pushrod checker and rotate engine until you're on base circle. Did this by feel because I didn't have the degree wheel installed. It's easy enough to observe.
2) Expand checker until rockers have next to no play in them when snugged down, but not to the point where they can't move at all and/or feel tight.
3) Remove rockers, remove checker tool and tape it up to prevent it from spinning. Reinstall and verify that nothing moved.
4) Remove and measure with calipers.
5) Reinstall checker again to verify that nothing moved during handling - ideally you get the same feel at the rocker that you did when you initially pulled it for measurement.
Using this method, my desired pushrod (gauge length) is the total measurement on the calipers - the washer thickness + my desired lifter preload.
for example: 7.741 - 0.060 + 0.030
I'm just about there, but want to compensate for the inaccuracy of the calipers as well. This tool is calibrated, but it still has an accuracy limited to +/- 0.002" + .0001*L (i.e. the longer your measurement the more uncertainty is attached to it). For example - I measured a 2" calibration standard and found that the calipers were reading 0.002" short. I'm going to use a 7" and 8" mic standard to determine how far off it is in my measurement range that I'm interested in. With those two error values, I'll be able to interpolate in between the two depending on what my checker measurement is and compensate accordingly.
More to come on this but wanted to post it up since it's fresh in my mind at the moment. In short, of the 8 lengths I've measured for so far, only 2 came out identical and there was as much as 0.050" variation between my required lengths. Pretty eye opening.....this is why you measure.
08-10-2013, 02:39 AM
#172
You realize Manton doesn't go by gauge length? I know you said Trend, but Manton FTW! You just throw your adjustable pushrod in there, f the number of turns - get it to zero lash and make your measurements. Take it out and measure it end to end.
Boom done.
Boom done.
08-10-2013, 07:36 AM
#173
Question for the engine builders following this thread.....
Is the pushrod length THAT critical to get all caught up in thousandths of an inch? I think 95% of the people on here are likely running....
1) An incorrect pushrod length
AND/OR
2) A pushrod that is only accurate to hundreths of an inch. i.e. 7.25". Does 0.005 mattter so long as the preload is proper?
I used the comp checker on my install. It seemed to work fine for me. I ended up making a "dummy proof" chart on paper that tells me the measurement at each click. Then I just turned it out to zero lash, removed it, counted turns and accounted for preload.
08-10-2013, 08:37 AM
#174
I don't think anything in this thread follows the "boom done" method, so why would he stop here?!? Haha. Just kidding around.
Question for the engine builders following this thread.....
Is the pushrod length THAT critical to get all caught up in thousandths of an inch? I think 95% of the people on here are likely running....
1) An incorrect pushrod length
AND/OR
2) A pushrod that is only accurate to hundreths of an inch. i.e. 7.25". Does 0.005 mattter so long as the preload is proper?
I used the comp checker on my install. It seemed to work fine for me. I ended up making a "dummy proof" chart on paper that tells me the measurement at each click. Then I just turned it out to zero lash, removed it, counted turns and accounted for preload.
Question for the engine builders following this thread.....
Is the pushrod length THAT critical to get all caught up in thousandths of an inch? I think 95% of the people on here are likely running....
1) An incorrect pushrod length
AND/OR
2) A pushrod that is only accurate to hundreths of an inch. i.e. 7.25". Does 0.005 mattter so long as the preload is proper?
I used the comp checker on my install. It seemed to work fine for me. I ended up making a "dummy proof" chart on paper that tells me the measurement at each click. Then I just turned it out to zero lash, removed it, counted turns and accounted for preload.
1) and 2) definitely exist out there - but there's more room for error if you are running lifters with a .100" preload window - .010" here or there isn't going to make or break you, so the bulk of the crowd have little reason to care and notice no ill effects. the johnson lifter's I've got require 0.025-0.030" as per the guy who designed them, so I'm going to try my best to hit that.
I realize what I'm doing isn't necessary for most people - it's just not in my nature to accept a sloppy measurement. Just figured I'd share to get a discussion going.
Last edited by ckpitt55; 08-10-2013 at 08:58 AM.
08-10-2013, 05:36 PM
#175
that would be fine if you assume that the oil hole through the real pushrods is the same diameter as the one in the checking tool. i wasn't sure so i went about the extra steps to measure according to the industry standard.
my problem with counting the turns is you really have no idea where you are on the last one. somewhere in that last 0.050" you're guessing. in addition to this, the pushrods themselves have machining tolerances. If I'm off on my initial measurement and they cut it at the extent of the tolerance then it's going to be extremely hard to make my preload consistent lifter to lifter (which is the end goal).
1) and 2) definitely exist out there - but there's more room for error if you are running lifters with a .100" preload window - .010" here or there isn't going to make or break you, so the bulk of the crowd have little reason to care and notice no ill effects. the johnson lifter's I've got require 0.025-0.030" as per the guy who designed them, so I'm going to try my best to hit that.
I realize what I'm doing isn't necessary for most people - it's just not in my nature to accept a sloppy measurement. Just figured I'd share to get a discussion going.
my problem with counting the turns is you really have no idea where you are on the last one. somewhere in that last 0.050" you're guessing. in addition to this, the pushrods themselves have machining tolerances. If I'm off on my initial measurement and they cut it at the extent of the tolerance then it's going to be extremely hard to make my preload consistent lifter to lifter (which is the end goal).
1) and 2) definitely exist out there - but there's more room for error if you are running lifters with a .100" preload window - .010" here or there isn't going to make or break you, so the bulk of the crowd have little reason to care and notice no ill effects. the johnson lifter's I've got require 0.025-0.030" as per the guy who designed them, so I'm going to try my best to hit that.
I realize what I'm doing isn't necessary for most people - it's just not in my nature to accept a sloppy measurement. Just figured I'd share to get a discussion going.
Edit:
If you want to go the extra step you could figure out the optimum preload. That would include some fluid dynamics and calculating the inertia of pushrod tip into the lfter cup at max desired RPM. You have the tools available already. Set up a diagram to understand the amount of force to push "x" weight oil at "y" temperature (you need need the msds data on the oil you're going to run for viscosities at different temps), as well as measure the normal force without intertia to the pushrod tip at 100% valve lift. Measure the force of the lifter spring and you should have every other piece of of the puzzle previously measured. Sounds easier than it is, but not entirely impossible to figure out.
Last edited by dirtbag; 08-10-2013 at 05:42 PM.
08-10-2013, 05:52 PM
#177
TECH Fanatic
My valvetrain is super quiet. Crazy quiet. Quieter than my OEM 6.1 Hemi. I hear everyone talking about the noise, and I don't know what is so special about mine. Just regular GM lifters, trunnion upgrade, comp pushrods, and 224 cam. I used the "known length" method with a dial indicator to measure the pushrod length. I'm at 0.045" preload.
08-10-2013, 06:24 PM
#178
The valvetrain engineers during the design phase of the engine have the luxury of autocad inventor or some other modeling program with their machining tolerances built in to tell them what size pushrods to run. The amount of time that goes into designing a valve train from the ground up is crazy, over a year for the entire development team. You are taking the correct approach to this ckpitt. While you won't have a silent valve train (which is dang near impossible without some sort of CAD software), it will definitely be one of the quietest out there in a modified application. Kudos man it's progressing nicely. A ton of garage innovation in here.
Edit:
If you want to go the extra step you could figure out the optimum preload. That would include some fluid dynamics and calculating the inertia of pushrod tip into the lfter cup at max desired RPM. You have the tools available already. Set up a diagram to understand the amount of force to push "x" weight oil at "y" temperature (you need need the msds data on the oil you're going to run for viscosities at different temps), as well as measure the normal force without intertia to the pushrod tip at 100% valve lift. Measure the force of the lifter spring and you should have every other piece of of the puzzle previously measured. Sounds easier than it is, but not entirely impossible to figure out.
Edit:
If you want to go the extra step you could figure out the optimum preload. That would include some fluid dynamics and calculating the inertia of pushrod tip into the lfter cup at max desired RPM. You have the tools available already. Set up a diagram to understand the amount of force to push "x" weight oil at "y" temperature (you need need the msds data on the oil you're going to run for viscosities at different temps), as well as measure the normal force without intertia to the pushrod tip at 100% valve lift. Measure the force of the lifter spring and you should have every other piece of of the puzzle previously measured. Sounds easier than it is, but not entirely impossible to figure out.
Originally Posted by White.Lighting
I admire what you are doing, and enjoy following. I was just questioning if thousandths mattered with pushrods.
Originally Posted by RezinTexas
You are contributing a lot to the community here, extreme detail-oriented OCD will pay off every time! Plus its a fun hobby...
I would have used the known length method, but it turns out that 7.400 wasn't even close to being long enough. I need in the neighborhood of 7.71x" - I'll post all the measurements when they're done. Haven't sat down and tried to figure out exactly why they're so different from stock yet - but I think it may be a combination of different lifter pushrod cup height with the Johnson's, having to shim the rockers, hand-work on the heads / valveseats, etc. Saw one of tony's pics from his 454 build and his lengths seemed to be similar, so hopefully that means I'm not completely off-base.
Last edited by ckpitt55; 08-10-2013 at 06:39 PM.
08-11-2013, 05:35 AM
#179
Chuck, since we have very similar setups I hope you don't mind if I put my pushrod measurements (which I made using the first set of Johnsons I had, the ones without the needles that ended up having an issue) in your thread. My stuff ended up coming out a little deep maybe ( I was shooting for 0.038" cold). Over the winter I will re-measure with the new lifters and cam as I do have a little bit of noise (cured by the Hy-per lube for now). I plan to also go double-tapered on the new set and may use your measurement technique if you get good results. Looks like your measurements are +0.050 from mine.
I have 8" HF calipers though, not Mitutoyo you lucky bastard. I realize I have 1 significant digit too many, but I was pretty surprised that the (digital) calipers did at least seem to be consistent to there.
Anyway, I just measured end to end after simultaneously adjusting two checkers for each set of YT's. . .in hindsight maybe I should have removed a rocker from each pair and just measured each valve separately. I measured each cylinder many times over the course of many days and averaged everything that looked "in family". . .I think it took me two weeks to measure for pushrods, LOL. Anyway, maybe this will be a useful datapoint for you as it gives folks an idea of the tolerances they can expect to be delivered and the variation between cylinders. Tony said at the time that he attributed most of the valve to valve variation to the rockers based on what he has seen.
BTW, don't trust my measured preload too much. That measurement was a not-so-careful sanity checking of my sanity check, which was counting the fractional turn to 28ft-lbs.
(If this post disrupts your qi let me know and I'll delete it with apologies.)
I have 8" HF calipers though, not Mitutoyo you lucky bastard. I realize I have 1 significant digit too many, but I was pretty surprised that the (digital) calipers did at least seem to be consistent to there.
Anyway, I just measured end to end after simultaneously adjusting two checkers for each set of YT's. . .in hindsight maybe I should have removed a rocker from each pair and just measured each valve separately. I measured each cylinder many times over the course of many days and averaged everything that looked "in family". . .I think it took me two weeks to measure for pushrods, LOL. Anyway, maybe this will be a useful datapoint for you as it gives folks an idea of the tolerances they can expect to be delivered and the variation between cylinders. Tony said at the time that he attributed most of the valve to valve variation to the rockers based on what he has seen.
BTW, don't trust my measured preload too much. That measurement was a not-so-careful sanity checking of my sanity check, which was counting the fractional turn to 28ft-lbs.
(If this post disrupts your qi let me know and I'll delete it with apologies.)
Last edited by therabidweasel; 08-11-2013 at 06:14 AM.
08-11-2013, 01:16 PM
#180
Steve, no worries at all man - thanks for posting that. This thread is about information, not just about what I have to share.
What pushrods are you running, manton?
As far as measuring preload, did you try mounting an indicator on the pushrod side of the rocker? If you zero it when the rocker's snug, it should readout what your lifter preload is fairly accurately at full torque.... if I'm not mistaken I think that's what Rezin did.
Btw, even those fancy mitutoyo calipers aren't perfect either...they have an advertized accuracy of +/- 0.002" and are calibrated, but I verified them at work to measure the "actual" error. From there I could generate my own calibration for the calibration and end up with a measurement with less error. I really hate using the word "perfect" because there's a fudge factor on everything, you just have to decide where your line in the sand is. You could probably do the same with the HF calipers and make your own compensation table assuming they're repeatable. I measured at 1" increments through the whole measurement range.
mic standards
Should be 2.000" on the nose, it's reading short.
I scaled the error by 100x so you could actually see it but this is what's going on. Since my measurement is between 7 and 8" and a slope exists in the error relative to those two points, I can interpolate between the two to arrive at the theoretical error at my measurement. In this instance I'll be compensating by some value less than 0.002".
And again, probably overkill - but just trying to show that nothing is perfect - everything has some tolerance or accuracy attached to it. If you want an accurate measurement, you have to try to capture all of your sources of error.
Speaking of which - my .140" washers were not really .140" - more like .145-.147". Discovered this when measuring the checker at what should be 6.800" gauge length (closed position) as a sanity check - I was measuring approx 6.785", which meant that the pushrod was passing through the washers too far. I may just add the difference to my overall measurement rather than trying to find something with exactly .140" id. Of course this is assuming that there's no error in the comp tool as far as length is concerned.
Further down the rabbit hole we go. Workin on car stuff today, will probably revisit length checking on the other side of the engine tonight.
Oh and I painted my oil pan with some engine enamel. I don't expect it to last long term but it'll at least look good on the engine stand lol
What pushrods are you running, manton?
As far as measuring preload, did you try mounting an indicator on the pushrod side of the rocker? If you zero it when the rocker's snug, it should readout what your lifter preload is fairly accurately at full torque.... if I'm not mistaken I think that's what Rezin did.
Btw, even those fancy mitutoyo calipers aren't perfect either...they have an advertized accuracy of +/- 0.002" and are calibrated, but I verified them at work to measure the "actual" error. From there I could generate my own calibration for the calibration and end up with a measurement with less error. I really hate using the word "perfect" because there's a fudge factor on everything, you just have to decide where your line in the sand is. You could probably do the same with the HF calipers and make your own compensation table assuming they're repeatable. I measured at 1" increments through the whole measurement range.
mic standards
Should be 2.000" on the nose, it's reading short.
I scaled the error by 100x so you could actually see it but this is what's going on. Since my measurement is between 7 and 8" and a slope exists in the error relative to those two points, I can interpolate between the two to arrive at the theoretical error at my measurement. In this instance I'll be compensating by some value less than 0.002".
And again, probably overkill - but just trying to show that nothing is perfect - everything has some tolerance or accuracy attached to it. If you want an accurate measurement, you have to try to capture all of your sources of error.
Speaking of which - my .140" washers were not really .140" - more like .145-.147". Discovered this when measuring the checker at what should be 6.800" gauge length (closed position) as a sanity check - I was measuring approx 6.785", which meant that the pushrod was passing through the washers too far. I may just add the difference to my overall measurement rather than trying to find something with exactly .140" id. Of course this is assuming that there's no error in the comp tool as far as length is concerned.
Further down the rabbit hole we go. Workin on car stuff today, will probably revisit length checking on the other side of the engine tonight.
Oh and I painted my oil pan with some engine enamel. I don't expect it to last long term but it'll at least look good on the engine stand lol
Last edited by ckpitt55; 08-11-2013 at 01:26 PM.