[Z06] Spring life (when to change valve springs?)
06-23-2018, 02:43 PM
#41
Racer
I respect a legit question. So the past few days I've been researching the valvetrain for the All Pro heads, as one does. The discussions that have emerged from the experts I've spoken to inevitably leads to the YT rockers. One expert wrote that he would "rather you run no rockers at all than the Yella diving boards", based off of spintron testing. So I have no facts of my own. The opinions I got are from people who, like I, have a favorable opinion of Tony Mamo, so he has nothing to do with any of those discussions. The engine builders I spoke to consider the YT to be an inferior product, and the only possible reason someone would even want to sell it is to make a profit, or "pushing parts" as they say.
So there is reason to suspect that the YT is a contributor to what lead my valvetrain to act up. Conceivably, a stiff enough spring can mask those effects...for awhile. This is all just my opinion, supported by expert opinions, and all of this could be dead wrong, or exactly on the money. Just my thoughts.
So there is reason to suspect that the YT is a contributor to what lead my valvetrain to act up. Conceivably, a stiff enough spring can mask those effects...for awhile. This is all just my opinion, supported by expert opinions, and all of this could be dead wrong, or exactly on the money. Just my thoughts.
The rockers are a 1.82...ish ratio, which is a tad bit more than the factory design. The higher the rocker ratio, the more lift, AND opening/closing speed that the spring sees. Could you share what you’ve learned about the YT rocker setup, that has influenced your decisions?
06-23-2018, 02:56 PM
#42
Melting Slicks
I can respect that. Honestly, YT has a bad reputation. That’s no secret. They have a serious history of broken parts, but have revised their products with each redesign along the way. I haven’t seen any broken rockers from the current generation, so they are making progress for sure. I for one would have never bought the YT setup, had it not have been for this rocker being made just for Tony and these heads. Tony put his name on them, which is one of the most respected names in the industry, so I said if it’s good enough for tony, it’s good enough for me.
The rockers are a 1.82...ish ratio, which is a tad bit more than the factory design. The higher the rocker ratio, the more lift, AND opening/closing speed that the spring sees. Could you share what you’ve learned about the YT rocker setup, that has influenced your decisions?
Here is a picture shared of a broken YT rocker, shared in a YT rocker discussion on fb yesterday. I do not know the details surrounding the picture.
06-23-2018, 03:03 PM
#43
Melting Slicks
I can respect that. Honestly, YT has a bad reputation. That’s no secret. They have a serious history of broken parts, but have revised their products with each redesign along the way. I haven’t seen any broken rockers from the current generation, so they are making progress for sure. I for one would have never bought the YT setup, had it not have been for this rocker being made just for Tony and these heads. Tony put his name on them, which is one of the most respected names in the industry, so I said if it’s good enough for tony, it’s good enough for me.
The rockers are a 1.82...ish ratio, which is a tad bit more than the factory design. The higher the rocker ratio, the more lift, AND opening/closing speed that the spring sees. Could you share what you’ve learned about the YT rocker setup, that has influenced your decisions?
06-23-2018, 03:11 PM
#44
Uhm....I was the only one that replied to you. Who else could you have been talking to?
Its not normal to change springs at 3k to 5k miles, but there’s absolutely nothing normal about Josh’s build, or my build either. They are both max effort solid roller, high lift, big duration builds, which is a far cry from what GM delivered to us in our cars. If and only if those springs get tested...then and only then can there be a determination made as to weather or not there is a problem with the setup. If there is a problem with the hardware, adjustments can be made to alleviate any issues. But the springs have to be tested first. All there is at this point is speculation and slander. Not cool. Those are the facts.
Im not taking sides. I’m a professional and don’t do that. So until the data is reviewed, which means the springs must be tested, why not keep our comments to ourselves.
You're the only one to respond to my comment?, I've only made one comment in this thread.
06-23-2018, 03:14 PM
#45
Then you need a new book.
A hand assembled, blueprinnted engine built for max performance is a race engine. An engine with a solid roller cam is an engine with a solid roller cam or an engine with "some" race parts on it.
A hand assembled, blueprinnted engine built for max performance is a race engine. An engine with a solid roller cam is an engine with a solid roller cam or an engine with "some" race parts on it.
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06-23-2018, 03:17 PM
#46
Melting Slicks
Very true. My exact thoughts also. An engine with a solid roller cam is an engine with a solid roller cam. Like the old saying "that car has it's blinker on, you know what that means? means it has it's blinker on"
06-23-2018, 03:20 PM
#47
OK what ever you say. I'm sure my 30+ years of racing in both NASCAR short track and NHRA Drag racing, not to mention two championships one as driver and one as a crew chief, oh and then there's my True Value Mechanic of the year award makes me ignorant. I guess the L88 427 wasn't a racing engine either.Technology has improved a lot but folks think that just because it came from a dealer with a warranty they can be lazy and then blame someone else when it fails. If you race it check your springs.
Secondly,
Technology has improved a lot but folks think that just because it came from a dealer with a warranty they can be lazy and then blame someone else when it fails
06-23-2018, 03:22 PM
#48
I can respect that. Honestly, YT has a bad reputation. That’s no secret. They have a serious history of broken parts, but have revised their products with each redesign along the way. I haven’t seen any broken rockers from the current generation, so they are making progress for sure. I for one would have never bought the YT setup, had it not have been for this rocker being made just for Tony and these heads. Tony put his name on them, which is one of the most respected names in the industry, so I said if it’s good enough for tony, it’s good enough for me.
The rockers are a 1.82...ish ratio, which is a tad bit more than the factory design. The higher the rocker ratio, the more lift, AND opening/closing speed that the spring sees. Could you share what you’ve learned about the YT rocker setup, that has influenced your decisions?
06-23-2018, 03:25 PM
#49
What I wrote about expert opinions is mostly everything I have come across with the YT rockers. Just saw your last question and wanted to respond to it. In sum, it lacks stiffness and is heavy, but the lack of stiffness is what is cited most. Those are the two most cited characteristics of the rocker. I don't think weight alone is the main criticism, because a big *** spring can control a heavy rocker, but the diving board effect is what kills it.
06-23-2018, 04:20 PM
#50
Pro
OK what ever you say. I'm sure my 30+ years of racing in both NASCAR short track and NHRA Drag racing, not to mention two championships one as driver and one as a crew chief, oh and then there's my True Value Mechanic of the year award makes me ignorant. I guess the L88 427 wasn't a racing engine either.Technology has improved a lot but folks think that just because it came from a dealer with a warranty they can be lazy and then blame someone else when it fails. If you race it check your springs.
^^^^^^^^^^^^ What He Said ^^^^^^^^^^^^^^
Deserved Repeating, and not being lost at the bottom of the Page.
06-23-2018, 04:33 PM
#51
Burning Brakes
That is an older gen rocker, as evidenced by the centered 1.7 stamp. Newer designs have the ratio stamp on left side, to more easily distinguish good from bad ones.
Last edited by edmundu; 06-23-2018 at 04:33 PM.
06-23-2018, 04:50 PM
#52
Racer
What I wrote about expert opinions is mostly everything I have come across with the YT rockers. Just saw your last question and wanted to respond to it. In sum, it lacks stiffness and is heavy, but the lack of stiffness is what is cited most. Those are the two most cited characteristics of the rocker. I don't think weight alone is the main criticism, because a big *** spring can control a heavy rocker, but the diving board effect is what kills it.
Not defending YT. Please don’t read into that. But I know you well enough to know that you understand that all aluminum rockers flex. I’m not sure that there is a fixture available to us, that would measure the amount of flex that a rocker sees. If aluminum doesn’t flex, it will break. Honestly to help us both sleep at night, we should have went with the steel Jessel Tomahawk units. I get bored easily with my stuff, and I may change mine out eventually to the Jesel’s. I really don’t care about the money side of things, fortunately.
Whatever cylinder head choice you end up with, throw a quality shaft setup on it.
I’ll stir the pot on this general rocker topic, totally unrelated to Josh. Hot Rod TV recently put a set of Summit...yes Summit...aluminum roller rockers on an LS engine. (LQ4 maybe?) They did back to back dyno tests, with stock rockers vs. the Summit aluminum rollers. The Summit rockers picked the engine up 9 hp. No other changes. People swear by the stock rockers being lighter and stiffer, therefor better. Dyno numbers (data) shows otherwise. I like data.
Last edited by Che70velle; 06-23-2018 at 04:51 PM. Reason: spellcheck strikes again...
06-23-2018, 05:45 PM
#53
Pro
The Engine that has been under discussion the last 20+ Posts in this thread (Josh's 454")
is an ERL "Blue Printed" and "Hand Assembled" Short Block with the Meticulously Assembled
Top End by the Owner with a .700" Lift Solid Roller Cam.
That should = Race Engine in anyones book!
Putting a solid roller in a completely stock OE assembly does not equal race engine,
however depending on the aggressiveness of the cam and how it is driven the valve train
including springs should be inspected as such.
Regarding the YT's I did not feel confident in them from my research for my application
and went with T & D s.
Certainly not an expert and willing to learn.
I will keep the book I have however
Thank You
06-23-2018, 07:16 PM
#57
The Engine that has been under discussion the last 20+ Posts in this thread (Josh's 454")
is an ERL "Blue Printed" and "Hand Assembled" Short Block with the Meticulously Assembled
Top End by the Owner with a .700" Lift Solid Roller Cam.
That should = Race Engine in anyones book!
Putting a solid roller in a completely stock OE assembly does not equal race engine,
however depending on the aggressiveness of the cam and how it is driven the valve train
including springs should be inspected as such.
Regarding the YT's I did not feel confident in them from my research for my application
and went with T & D s.
Certainly not an expert and willing to learn.
I will keep the book I have however
Thank You
is an ERL "Blue Printed" and "Hand Assembled" Short Block with the Meticulously Assembled
Top End by the Owner with a .700" Lift Solid Roller Cam.
That should = Race Engine in anyones book!
Putting a solid roller in a completely stock OE assembly does not equal race engine,
however depending on the aggressiveness of the cam and how it is driven the valve train
including springs should be inspected as such.
Regarding the YT's I did not feel confident in them from my research for my application
and went with T & D s.
Certainly not an expert and willing to learn.
I will keep the book I have however
Thank You
No, the engine that was being referenced as a race engine was the C6 Z06 LS7.
BTW, my 434 is an ERL "Blue Printed" and "Hand Assembled" Short Block by Justin Yoder at ERL.
06-23-2018, 07:21 PM
#58
Again it depends on the use. If you purchase the car to race it and you do then yes. Not everyone races their car. It seems to me that even a stock LS7 is at the very least a "high performance engine" maybe not a full blown race engine but if raced should be treated as such. If I remember correctly the OP's engine was modified and he intended to do some racing.
Last edited by tomcat11; 06-23-2018 at 07:22 PM.
06-23-2018, 07:32 PM
#59
I am merely saying if you race the engine on a track, WOT, at high rpm under high heat conditions with relatively high oil temperatures on a regular basis it would be prudent to MONITOR the valve springs and change the oil frequently. Both are considered consumable items. Especially oil which can break down and become diluted with fuel.
Again it depends on the use. If you purchase the car to race it and you do then yes. Not everyone races their car. It seems to me that even a stock LS7 is at the very least a "high performance engine" maybe not a full blown race engine but if raced should be treated as such. If I remember correctly the OP's engine was modified and he intended to do some racing.
Again it depends on the use. If you purchase the car to race it and you do then yes. Not everyone races their car. It seems to me that even a stock LS7 is at the very least a "high performance engine" maybe not a full blown race engine but if raced should be treated as such. If I remember correctly the OP's engine was modified and he intended to do some racing.
I get that and to a point agree, I check over my car frequently but GM markets this car as track ready and makes no mention of needed to periodically check the valve train.