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Despite what the BTR rep told you, I don't believe you have enough spring for that cam. I bet your issue was valve control and that is what took out the lifter.
I have a 2015 Z28 and recently I had a lifter fail. Johnson 2110r. It really took out the whole engine, down to the block itself. I am looking at alternative block options because the LS7 blocks arent strong and are very hard to find in good shape by themselves. I have a LC9, LS1 and L33 block laying around my house. Has anyone sleeved any of those blocks to 4.125? I just had an LS3 block done by RED for my truck, but he mentioned he doesnt reccomend doing it to gen3 blocks because of the coolant passages between the cylinders. He didnt elaborate much. I wasnt planning on the camaro having problems anytime soon so Im caught on a really tight budget to get this back on the road. Looking for input from people who have ACTUALLY had gen3/gen4 blocks sleeved to 4.125. I want to know about Longevity mostly. I can srouce another LS3 block but if i dont need to, I dont want too. I really want an RHS block, but they are disgustingly expensive. Thanks
In my .02, the springs are marginal if you're running 7,000rpm with stainless valves in LS7 sizes. I have to agree with others on this. My cam is 12°-14° shorter on duration, .060" lower lift, and Tony Mamo has told me my PAC springs are just right shimmed to 1.75" installed height instead of 1.800 PAC specs. They are 160lbs seat, and 425lbs over the nose. These specs are at 1.800" installed height. Without doing the math, I would guess my springs are approx. 165lbs seat, and 430lbs over the nose when shimmed to 1.75" installed height. In any event, and even if your springs didnt cause this failure, I believe you're on the ragged edge. I know it's only .002", but you are already just over their max recommend lift. I've been wrong before, but with that cam and those springs, I'd either shift at 6,800rpm max, or go to .700" lift springs. Again, my .02.
In my .02, the springs are marginal if you're running 7,000rpm with stainless valves in LS7 sizes. I have to agree with others on this. My cam is 12°-14° shorter on duration, .060" lower lift, and Tony Mamo has told me my PAC springs are just right shimmed to 1.75" installed height instead of 1.800 PAC specs. They are 160lbs seat, and 425lbs over the nose. These specs are at 1.800" installed height. Without doing the math, I would guess my springs are approx. 165lbs seat, and 430lbs over the nose when shimmed to 1.75" installed height. In any event, and even if your springs didnt cause this failure, I believe you're on the ragged edge. I know it's only .002", but you are already just over their max recommend lift. I've been wrong before, but with that cam and those springs, I'd either shift at 6,800rpm max, or go to .700" lift springs. Again, my .02.
I'm not sure about the springs given that all the other lifers are fine. When measuring, the springs were installed at 1.8. They coil bind at 1.07. So lift wise they have a lot of buffer room for bind. Pressure wise, they should be around 410# open at this lift. They didn't recommend anything over 430# so this is right near the limit of the stock rocker arm tip anyway. BTR specifically uses these springs with this camshaft without issue and directly recommended them. The place that did the tuning for me was RPM. They have a direct competitive camshaft for the BTR LS7 4v2 called the B3, and they made no remarks as to the springs being inadequate. They didn't experience any float issues or noises during tuning either. Like I mentioned before, I don't drive the car hard often at all. I drive the thing to work mostly and personally have never tracked it. What ever hard driving it gets is mild at best and is short road pulls off a stop light. Nothing even near 7000rpm. Tuning is legitimately the only time it saw 7000 with that camshaft. Way too many cops in my area for a car this loud to stretch its legs on the street without garnering attention. This lifter also failed during normal driving, and gave me no audible warning leading up to the failure at all. Which was weird by itself. The only real clue I have found so far is the roller pin had a deep grove right in the center that looked like something locked up and ground it away fairly quickly. Regardless, so far it seems that neither Johnson nor BTR are going to step up and deal with this failure. I'm still out a $20K engine for a $50 part and I'm pissed off.
I don't blame you for being pissed off. I'd REALLY be pissed off. In my experiences, when this stuff happens, you'll be lucky to get 1 replacement lifter under the "warranty," while the other collateral damage may (but probably not) get you an I'm sorry for your loss. I once had a new set of 225 AFR heads. This was WAY back in 2004, and were some of the earliest 225s AFR sold. I paid extra for Ferrea valves, and REV valvesprings. While still breaking the engine in with just 300 miles on it, a valvespring broke, at maybe 2,500 rpm. Lucky the valve didn't drop, or have any junk go down the oil drain holes. This happened because AFR screwed up the metric to SAE conversion, and the installed height was around 1.680" instead of 1.780". All I got from AFR was an option to buy Comp 921 springs at their cost!! No we're sorry this happened, nothing. So, even the best products have failures once in a while. The fact that the other 15 lifters are fine (if in fact they are) does support your viewpoint.
Correct. As well as using a Spring only rated to .660 lift.BTR LS7 STAGE 4 V2 CAMSHAFT
246/26X, .662"/.662", 111 LSA
INTAKE LOBE LIFT @ TDC: 0.09390
You guys are missing an important fact that advertised lift is typically not true lift at the valve. Deflection, tolerances, etc all add up. That being said, I have seen the lift limits Johnson puts on their lifters and it really does not make a whole lot of sense. They can have a lobe lift limit, which would correlate to what the lifter actually sees at the cam.Total lift is derived from the rocker ratio x lobe lift which can vary. All that being said, I have seen .700+ lift on any/all of the Johnson lifters without an issue in a variety of builds. Hell, I'm getting ready to do my 392 w/ used 211r Johnson's w/ 480# open Comp springs. Opinions will vary on the spring rate, but I would never run that little spring on that much cam. I know BTR basically builds their whole lineup around that .660 spring kit, but my experience is they wear out real quick,like 20-30#'s off on the seat pressure in 30k miles. Have seen it a few times, including my own 6.0 build. I don't like anything less than 450# open on a dual spring setup unless valvetrain is super light. Another thing is the cam itself. Can grinders screw up too, I would pull the cam and mic the lobes and see what actual lobe lift was on the bad one. So many variables, but my gut feeling is Johnson is not the direct blame. Measure everything, pushrods, valve height, etc. 90% chance there is a smoking gun somewhere.
You guys are missing an important fact that advertised lift is typically not true lift at the valve. Deflection, tolerances, etc all add up. That being said, I have seen the lift limits Johnson puts on their lifters and it really does not make a whole lot of sense. They can have a lobe lift limit, which would correlate to what the lifter actually sees at the cam.Total lift is derived from the rocker ratio x lobe lift which can vary. All that being said, I have seen .700+ lift on any/all of the Johnson lifters without an issue in a variety of builds. Hell, I'm getting ready to do my 392 w/ used 211r Johnson's w/ 480# open Comp springs. Opinions will vary on the spring rate, but I would never run that little spring on that much cam. I know BTR basically builds their whole lineup around that .660 spring kit, but my experience is they wear out real quick,like 20-30#'s off on the seat pressure in 30k miles. Have seen it a few times, including my own 6.0 build. I don't like anything less than 450# open on a dual spring setup unless valvetrain is super light. Another thing is the cam itself. Can grinders screw up too, I would pull the cam and mic the lobes and see what actual lobe lift was on the bad one. So many variables, but my gut feeling is Johnson is not the direct blame. Measure everything, pushrods, valve height, etc. 90% chance there is a smoking gun somewhere.
I understand it quite well. I have spoken to Johnson's tech support in the past about these very lifters as well as have them in my own motors. You asking alot out of those trays at those lifts to keep them stable and tracking straight. Hopefully they were OEM trays...
I have dealt with BTR and their Sales People in the past also... Frankly their house brand lifter trays are junk. I wish I would have kept them so I could show the difference between an OEM one. They are softer than the OE.
With that much lift, I personally would have used a link Bar set up. At minimum BTR sales an SK702 spring kit rated up to .685 lift. Like you said there stuff can and will wear over time. You want some head room built in.
I have .660 lift at the valve and using factory oe lifters from a 1xx mile old 2006 ls2, with new GM lifter trays. Has seen 8k rpm shifts. Still runs perfect. Although i do have titanium valves. Springs are PSI duals that i have no idea what pressure, they came with the heads
I highly doubt OP's failure was lift related or spring related. Sometimes parts just fail. Personally i still trust the oe gm lifters that came in their engines from the factory and i will happily use them again if i know they were good beforehand with no noises, and they check out ok visually, before i use any aftermarket lifters. Because i've owned several high rpm ls's over the past 2 decades all running their factory oe lifters and i still haven't had one fail yet
I also run 15/40 diesel oil and whenever someone tells me i should be using a car racing oil i close my ears
I understand it quite well. I have spoken to Johnson's tech support in the past about these very lifters as well as have them in my own motors. You asking alot out of those trays at those lifts to keep them stable and tracking straight. Hopefully they were OEM trays...
I have dealt with BTR and their Sales People in the past also... Frankly their house brand lifter trays are junk. I wish I would have kept them so I could show the difference between an OEM one. They are softer than the OE.
With that much lift, I personally would have used a link Bar set up. At minimum BTR sales an SK702 spring kit rated up to .685 lift. Like you said there stuff can and will wear over time. You want some head room built in.
Mr Brick, I apologize, I wasn't targeting my post specifically towards you, it's just that happened to post the cam specs. I see your posts, I know you know your stuff👍. It's interesting what you say on the Johnsons uncovering the oil hole. I have my set of 2110r buried, will have to dig out and compare to some LS7's on the bench now. The whole tray thing vs lift is inconclusive, to my knowledge, nobody has ever really measured it out to see at what lobe lift there is contact.
Mr Brick, I apologize, I wasn't targeting my post specifically towards you, it's just that happened to post the cam specs. I see your posts, I know you know your stuff👍. It's interesting what you say on the Johnsons uncovering the oil hole. I have my set of 2110r buried, will have to dig out and compare to some LS7's on the bench now. The whole tray thing vs lift is inconclusive, to my knowledge, nobody has ever really measured it out to see at what lobe lift there is contact.
1.No worries.
2.Uncovering the oil hole??? That was not my comment.
I did comment on the lift relative to the lifter tray. This particular design that GM uses was not really meant for what we ask out of it on the performance side. It would be cool to see the original design and testing data to see what they thought it could safely handle.
Based on conversations I have had with Johnson tech support, Some Cylinder head Guru's, and a few Engine builder's, I have come to my own conclusion that in my opinion, when going to lifts above the .600 range, It's wise to invest in link bar lifters. Again Just my Opinion. I could not give an actual number above .600 lift where it would be a requirement.
I feel looking at failure like this is an excellent way for us all to learn something.
I may be wrong, but please bear with me. IMHO, when you start lifting valves .660"+, with 250°+ duration, you're knocking on the door of racing cams. As good as Johnson lifters are, nobody is perfect. Again, my 2 cents, but I think he simply got a bad lifter. Especially if the other 15 look fine. That or the cam grinder made a mistake on one lobe, which is hard(er) to do these days with CNC equipment. When I recently tore the heads off my LS7 due to #8 exhaust being totally shot, I was very surprised that the #8 Exh guide was the only guide worn to that degree. None of the rest were close. So, did I get 1 bad guide out of 16? Maybe so. Just like maybe the OP got 1 bad lifter out of 16. Stuff happens, and that may be why we both experienced what we did. My speculation, nothing more.....
Johnson currently has my failed lifter set and is evaluating what they think happened. I don't expect them to come back with a smoking gun as it were. They will likely give a generic explanation and offer to just replace the one lifter like they did for my failed lifter in my 392 hemi. All the other 15 lifters looked basically new. As did the trays. As stated previously, I used the parts that were recommended to me for the camshaft by BTR. Nothing more or less. As it stands now, I am not going back to a stock LS7 block. I am getting a DART 31947222 block after a few more paychecks or I'll just cash out a few investments to make it happen. I just don't trust the stock blocks to handle what I have in mind to do with the car anymore. I am still having my block repaired, and it is looking like it is repairable with the help of some Darton sleeves and my local machine shop being very dedicated to seeing it fixed. What I do with it after it is repaired, I'm not sure. He also has my PRC heads, and said all the exhaust valve guides looked new, but ALL the intake guides are trashed. So there's that too. I am going to get T&D steel roller tip rocker arms and new PSI springs tailored for my new camshaft. I am having cam motion work on a custom grind for this new NA build. I'm probably going to sell the titanium rods, as with my aerospace experience at work, that material is seen as a fatigue point when it sees aggressive compression / tensile loads. Its time for some forged steel units. Once I get an answer from Johnson about what they think happened, I'll post it here. Thanks for all the thoughts and info so far guys. I appreciate it a lot.
Johnson currently has my failed lifter set and is evaluating what they think happened. I don't expect them to come back with a smoking gun as it were. They will likely give a generic explanation and offer to just replace the one lifter like they did for my failed lifter in my 392 hemi. All the other 15 lifters looked basically new. As did the trays. As stated previously, I used the parts that were recommended to me for the camshaft by BTR. Nothing more or less. As it stands now, I am not going back to a stock LS7 block. I am getting a DART 31947222 block after a few more paychecks or I'll just cash out a few investments to make it happen. I just don't trust the stock blocks to handle what I have in mind to do with the car anymore. I am still having my block repaired, and it is looking like it is repairable with the help of some Darton sleeves and my local machine shop being very dedicated to seeing it fixed. What I do with it after it is repaired, I'm not sure. He also has my PRC heads, and said all the exhaust valve guides looked new, but ALL the intake guides are trashed. So there's that too. I am going to get T&D steel roller tip rocker arms and new PSI springs tailored for my new camshaft. I am having cam motion work on a custom grind for this new NA build. I'm probably going to sell the titanium rods, as with my aerospace experience at work, that material is seen as a fatigue point when it sees aggressive compression / tensile loads. Its time for some forged steel units. Once I get an answer from Johnson about what they think happened, I'll post it here. Thanks for all the thoughts and info so far guys. I appreciate it a lot.
Dansic, I have a few follow up questions.
Were the Lifter Trays AC Delco or BTR trays? AC DELCO are individually packaged in their respective ac delco labeled bags. The BTR's are in a generic clear bag with a white label. Side by side the look similar however the BTR's do not have a part number molded into the part.
If you have the valve springs tested, let us know if they are within spec or if they are week. Your shop should be able to pull one and test it for you. Preferably on the one where the lifter failed. Was it an intake or exhaust lobe?
Were the Lifter Trays AC Delco or BTR trays? AC DELCO are individually packaged in their respective ac delco labeled bags. The BTR's are in a generic clear bag with a white label. Side by side the look similar however the BTR's do not have a part number molded into the part.
If you have the valve springs tested, let us know if they are within spec or if they are week. Your shop should be able to pull one and test it for you. Preferably on the one where the lifter failed. Was it an intake or exhaust lobe?
They were BTR trays according to my order sheet. BTR95365-4. All of my valve springs are being tested, I will know the results when I pick the heads up from the machine shop. The failure occurred on the #1 exhaust valve.
Lift is the difference between the radius of the nose and the radius of the heel.
The nose of the cam is always as large as it can be, and still be able to go through the bearings to install it. (or mighty close to it) They make a cam "bigger" by making the heel SMALLER. Which is why you can nearly always have a cam reground "bigger", but often not "smaller".
The lifter therefore descends farther into the block as the lobe lift becomes greater. The higher the lift, the less secure the whole tray system is. At some point, the lifter will fall out of the tray, and be able to turn. Once that happens it's all over.
I would suspect that that's what happened here.
Consider also, that there's no spring or whatever else, holding the trays exactly in place. Obviously they can't move very far, but they're not absolutely secured. If one happens to get pushed up a bit for whyever, one of the other lifters it controls could fall out, in which case, the failed one isn't the "root cause" of the actual failure; it's just the victim.
Which adds to the argument for using link-bar lifters once lift exceeds some threshold. No idea what that threshold is, but .600" seems like a decent guess at where to at least start looking at it.
06-19-2024, 09:32 PM
