Pushrod length; I know I know...sorry
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From: Central, FL
Pushrod length; I know I know...sorry IS it possible that my '00 LS1 with recently installed LS6 cam needs 7.35" push rods? TDC on #1 & 6 cylinder and that's what I came up with following instructions and reading several posts using p/r lenght checker.
6.8" and 9.625 turns at .050" = 6.8" + .48125" + .060" ( preload) = 7.34125".
All's I hear is due to the smaller base circle that I should be at 7.425".
There are a lot of miles on her, around 150k+. Is it possible that somewhere along the line that during a rebuild the heads or block were/was decked,shaved (proper term eludes me)? In that case, the p/r lenght would decrease.
The 7.4's that are in her now had the valves opening as I was tightening rockers down during reassembly. And assuming the oil had bled out of those lifters doesn't explain things because wouldn't the plunger be further recessed into the lifter bore leading to a longer p/r? Even IF the oil bled, then the internal spring would force the plunger to the top anyways. I really think I have done things correctly, but if anyone can shed some light on this dead horse I'd appreciate it.
I know there are better cams out there after reading, but I'm sticking with this one... for now.
6.8" and 9.625 turns at .050" = 6.8" + .48125" + .060" ( preload) = 7.34125".
All's I hear is due to the smaller base circle that I should be at 7.425".
There are a lot of miles on her, around 150k+. Is it possible that somewhere along the line that during a rebuild the heads or block were/was decked,shaved (proper term eludes me)? In that case, the p/r lenght would decrease.
The 7.4's that are in her now had the valves opening as I was tightening rockers down during reassembly. And assuming the oil had bled out of those lifters doesn't explain things because wouldn't the plunger be further recessed into the lifter bore leading to a longer p/r? Even IF the oil bled, then the internal spring would force the plunger to the top anyways. I really think I have done things correctly, but if anyone can shed some light on this dead horse I'd appreciate it.
I know there are better cams out there after reading, but I'm sticking with this one... for now.
The factory p.r.s are actually 7.385" and the valves of an LS6 are .0236" longer to make up for the reduced camshaft base circle.
It's difficult to know if your heads have ever been off before but either some one wacked em' a bunch for compression and most likely would have cammed it at that time or just a clean up cut/valve job in which case a few thousandths is negligible.
Its also important to know which LS6 camshaft you have as the 01 had .525" lift and the 02-04 were .551"/.547" lift.
I'm betting 7.4 will be your cup of tea and the lifter plungers are just still holding pressure and need to recorrect. Remember that that internal mechanism has to be stout enough to deal with some pretty elevated valve events and spring pressures.
It's difficult to know if your heads have ever been off before but either some one wacked em' a bunch for compression and most likely would have cammed it at that time or just a clean up cut/valve job in which case a few thousandths is negligible.
Its also important to know which LS6 camshaft you have as the 01 had .525" lift and the 02-04 were .551"/.547" lift.
I'm betting 7.4 will be your cup of tea and the lifter plungers are just still holding pressure and need to recorrect. Remember that that internal mechanism has to be stout enough to deal with some pretty elevated valve events and spring pressures.
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Thanks, it's an '02-'04 cam. It's got the GM stamp on it too.
The cam that came out was the correct number also and GM stamped as well.
Yeah I didn't think they may have "wacked" down on the bolts and I'm surprised to see the stock cam come out (if at one point there was a rebuild) as compared to not putting something in for performance. Stock is never enough IMHO.
I'm actually going to go through a couple cylinders again and do it a way I found somewhere here last night during night shift. I'm going to do the opposite valve of the one that's fully open. And I now realize that doing 1 & 6 was wrong to do at the same time. I swear I used the search button and kick myself in the ars.
And 10-4 on the internal mechanical events.
Thanks again.
The cam that came out was the correct number also and GM stamped as well.
Yeah I didn't think they may have "wacked" down on the bolts and I'm surprised to see the stock cam come out (if at one point there was a rebuild) as compared to not putting something in for performance. Stock is never enough IMHO.
I'm actually going to go through a couple cylinders again and do it a way I found somewhere here last night during night shift. I'm going to do the opposite valve of the one that's fully open. And I now realize that doing 1 & 6 was wrong to do at the same time. I swear I used the search button and kick myself in the ars.
And 10-4 on the internal mechanical events.
Thanks again.
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Put most of the rockers on then check. the rocker stand has to be tight to. The head or it will mess up your measurements an easy way to do is turn motor over until intake valve starts to open then check exhaust valve of same piston
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Thanks jimmyg, I'll try that measuring method tomorrow, but FWIW, I did have the all of them in and torqued for that reason.
I've got all of the pr's in now and torqued the rocker bolts.
My new solenoid for the starter came in today (that I messed up... still can't believe I did that). I'm going to install the starter and turn her over until oil comes out the pr's and pick a cylinder or two and do a compression check with the stock pr's in and see what happens. I just want to verify that the valves that opened a little upon tightening the rocker bolts seat properly after rotating the engine a little and allowing the oil pressure to build. I may just put everything back together and hope I didn't actually need the shorter pr's, either that or I'll wonder if the 7.425's are necessary.
I can't even imagine what the preload was with the stock cam in there considering it seems even too much with the smaller base circle of the LS6 cam.
Quick q... do I need to clean the rocker bolt holes of oil and the bolts so locktite can be used on the rocker bolts?
Well if anything I'll swap in the Prothane motor mount inserts tomorrow. I really need to accomplish 'something'. The left side is pretty bad.
Thanks for the help so far.
I've got all of the pr's in now and torqued the rocker bolts.
My new solenoid for the starter came in today (that I messed up... still can't believe I did that). I'm going to install the starter and turn her over until oil comes out the pr's and pick a cylinder or two and do a compression check with the stock pr's in and see what happens. I just want to verify that the valves that opened a little upon tightening the rocker bolts seat properly after rotating the engine a little and allowing the oil pressure to build. I may just put everything back together and hope I didn't actually need the shorter pr's, either that or I'll wonder if the 7.425's are necessary.
I can't even imagine what the preload was with the stock cam in there considering it seems even too much with the smaller base circle of the LS6 cam.
Quick q... do I need to clean the rocker bolt holes of oil and the bolts so locktite can be used on the rocker bolts?
Well if anything I'll swap in the Prothane motor mount inserts tomorrow. I really need to accomplish 'something'. The left side is pretty bad.
Thanks for the help so far.
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From: Central, FL
... and one more thing. I have been tightening the rocker bolt on whichever one I'm checking with the PR length checking tool to 22 ft/lbs for the zero lash and then adding x.050" the turns of the checker, 6.8" and .060" to that (as stated in the first post). It doesn't make sense to me not to do it that way. If the preload is indeed preload, then zero lash needs to be set with it torqued to spec IMO.
If I do it just hand tight there is movement when I torque it down, how could that not lead to errors. I hope I'm explaining this so it's understood what I mean.
It sucks that I got the pr checker and am still 2nd guessing my results. I think I may pull the timing chain cover back off and replace the oil pump o-ring too. Who knows if it got replaced when/if any work was done? I definately remember a little twitch associated with the reading, but attributed it to the age of the car/sensor/milage.
If I do it just hand tight there is movement when I torque it down, how could that not lead to errors. I hope I'm explaining this so it's understood what I mean.
It sucks that I got the pr checker and am still 2nd guessing my results. I think I may pull the timing chain cover back off and replace the oil pump o-ring too. Who knows if it got replaced when/if any work was done? I definately remember a little twitch associated with the reading, but attributed it to the age of the car/sensor/milage.
Exhaust cracks open: set int valve
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I know this probably doesn't help you much...but, I used the same LS-6 "5308" cam in my 5.3L build...I went with 7.425" length pushrods. I did a lot of research and a lot of measuring...this seems to be the most common length I've seen used on the cam. Worked great for me, no sewing machine noise, runs great. (Sorry I can't find my measurements to post right now.)
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From: Central, FL
10-4 voda1, I'll check it using both methods and see if there's a difference either way and post results so maybe it'll help clarify for anyone who finds this thread.
Anybody got any thoughts on the fact I'm torqueing to spec b4 zero lash findings? I still feel like that would give accuracy... thoughts? If I'm dead wrong, I'd rather know now then find out I should've done things differently when the car is put back together (body is raised off engine/tranny/cradle via lift).
It really does suck doing this stuff while on night shift... motivationally challenged me am (sorry; watching Wheeler Dealers on Velocity).
Thanks.
Anybody got any thoughts on the fact I'm torqueing to spec b4 zero lash findings? I still feel like that would give accuracy... thoughts? If I'm dead wrong, I'd rather know now then find out I should've done things differently when the car is put back together (body is raised off engine/tranny/cradle via lift).
It really does suck doing this stuff while on night shift... motivationally challenged me am (sorry; watching Wheeler Dealers on Velocity).
Thanks.
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From: Central, FL
I know this probably doesn't help you much...but, I used the same LS-6 "5308" cam in my 5.3L build...I went with 7.425" length pushrods. I did a lot of research and a lot of measuring...this seems to be the most common length I've seen used on the cam. Worked great for me, no sewing machine noise, runs great. (Sorry I can't find my measurements to post right now.)
I don't need to hurry anymore tho cuz I ordered an oil pump pickup tube to pump inlet o-ring last night at work. I may as well pull the timing chain cover back off too to be a step ahead when it shows up; oh and the pump (and damn it may as well port the pump). It never ends!
Your 5.3... what was it in? I've been thinking about putting a 5308 in my '00 RCSB step-side with 5.3 (207k miles). I put in an LQ9 cam and LS6 springs and it's a little better than stock, but it could be better. At least the base circle is = tho, so I didn't even think of if the pr's would be an issue (and they're not... she is quiet as a mouse). It really is fun embarrassing ppl with my beater truck with a ladder rack. The best one was a '13 BRZ... those things are pathetic IMHO.
Ok I'm babbling again, sorry.
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From: Central, FL
[QUOTE=It is with a station wagon also...[/QUOTE]
VERY nice. 3 questions, how much does she weigh? What's the stall (assumed auto) and rear end gears? My guess is from 3.08 to 3.55s. I know, broad spectrum, but still a guess none the less, lol.
VERY nice. 3 questions, how much does she weigh? What's the stall (assumed auto) and rear end gears? My guess is from 3.08 to 3.55s. I know, broad spectrum, but still a guess none the less, lol.
Last edited by 00-SLP; Nov 29, 2014 at 07:33 PM. Reason: Quoted wrong post.
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Well I got the starter back on for oil priming, but my Harbor Freight booster doesn't have enough oomph to turn her over hard enough to prime everything. I did have oil coming up maybe 3 pr's tho, so she's on her way. I hooked up the compression tester to 1 &3 cylinders and I got 160 psig on both. Considering I did not have the throttle blade propped open and the battery was as weak as it is, that's pretty good I guess. That at least tells me that the pr's are not preventing the valves from closing and seating properly. 7.425s might be in order afterall. Tomorrow I'll pull the battery out of the beater and run the starter, she'll go like a raped ape then. Then compression test again and check pr lenght and final decision time. There's a light at the end of this tunnel.
Thanks man...
Thanks...I haven't weighed it yet...I'm almost embarrassed to tell you I used the stock truck converter, (this was a very LOW budget build, I probably have less than 3 grand total in this thing) I used a set of 3.73 gears I had laying around.
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Hey so you know, if it's a 4L60E you can use a stock converter for a 6 cylinder Trail Blazer ( I think it was a BU-51). It held on my Silverado SS with Powerdyne, so you should be fine with it. They are pretty cheap like $150 or close to it. I just got an upgraded one from Florida Torque Converters through ebay for $175.00 to my door and I guess they do some stuff to it. It seems a little different that the 6-TB one, but prolly cuz I paid a little more for it. I have to tell myself it's better so I don't have to kick myself in the ars for doing the work. Now the old vert will go into my beater.
Have fun with your not so sleepy sleeper. It looks a lil mean to me, lol.
Have fun with your not so sleepy sleeper. It looks a lil mean to me, lol.