LS1 Valve Spring Issues. . ..
#1
LS1 Valve Spring Issues. . ..
The Bristol Cup race is next week. A good friend of mine is a spring engineer at one of the major suppliers for our market. He is also a Jr. fan. . .good man. Anyway, he will be here from Wednesday, 25th, on so I am going to pick his brain and may have him log on here to look at the issues that this engine is running into. This engine has way to many spring failures compared to other markets, hell BBC marine engines running 4000 and 5000 rpm all day long will last 30K miles based on the hours they run.
If anyone has any specific questions you want asked, either post them or PM me. Thursday the 26 is no racing so I may log on that day with him.
Chris
If anyone has any specific questions you want asked, either post them or PM me. Thursday the 26 is no racing so I may log on that day with him.
Chris
#3
2xLS1,
I agree. With the weight of the hyd roller and what you have mentioned I agree. Although the Ford 5.0 community approaches close to what the LS1's are running and also have a heavier lifter, but have no where near the spring issues. I don't know if it is due to the larger 1.460" OD stuff that is run or what. We shall try and find out.
Chris
I agree. With the weight of the hyd roller and what you have mentioned I agree. Although the Ford 5.0 community approaches close to what the LS1's are running and also have a heavier lifter, but have no where near the spring issues. I don't know if it is due to the larger 1.460" OD stuff that is run or what. We shall try and find out.
Chris
#5
Viper,
Our locks have been shipping since April. Everyone is happy. I would not use a stock lock, stock black oxided lock, or a lock that fits like the OEM one does in the OEM retainer on a modified engine. There is to much movement of the lock in the groove area. Compound that with a little valve float and you have a recipe that will hurt something.
Our lock must be used with an AFR retainer or Patriot retainer for Super 7.
Chris
Our locks have been shipping since April. Everyone is happy. I would not use a stock lock, stock black oxided lock, or a lock that fits like the OEM one does in the OEM retainer on a modified engine. There is to much movement of the lock in the groove area. Compound that with a little valve float and you have a recipe that will hurt something.
Our lock must be used with an AFR retainer or Patriot retainer for Super 7.
Chris
#6
I think you will find that the reason this engine has more valve-spring issues than most engine is not necessarily a problem with the engine or the springs. This is a common engine, and just as commonly, people try to test the limits of the engine...particularly how far you can rev it, and how much lift you can jam onto those springs as quickly as possible.
#7
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Originally Posted by Another_User
I think you will find that the reason this engine has more valve-spring issues than most engine is not necessarily a problem with the engine or the springs. This is a common engine, and just as commonly, people try to test the limits of the engine...particularly how far you can rev it, and how much lift you can jam onto those springs as quickly as possible.
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#8
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Originally Posted by Another_User
I think you will find that the reason this engine has more valve-spring issues than most engine is not necessarily a problem with the engine or the springs. This is a common engine, and just as commonly, people try to test the limits of the engine...particularly how far you can rev it, and how much lift you can jam onto those springs as quickly as possible.
#9
Originally Posted by Fireball
how many other engines use 1.7 rockers? That makes for some wicked valve velocities...
If I have two cars and one has headers and one has a lid, and they both finish the quarter mile at the same time, which one is faster? The answer is neither. The end result (theoretically guys, I know headers and intake will create different horsepower and torque curves, blah blah blah) is the same.
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Originally Posted by Another_User
I guess. It still comes down to your cam profiles and you final lift value, neither of which are too crazy stock. The 1.7 rockers are just a multiplier...based on the cam the end result is pretty much the same.
but with wicked lobes out there today...that 1.7 multipler is a BIG factor IMHO
#11
Originally Posted by Fireball
but with wicked lobes out there today...that 1.7 multipler is a BIG factor IMHO
#13
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One problem I see is the high lift and rpms like I said earlier, and people just throwing springs on the heads without checking the installed height. Who actually sets their spring height? Isn't Crane saying installed height effects the harmonics in the spring? Take a look at the broken Crane spring thread. People are saying use this shim or that shim when the only way to know what, if any shim you need it to use one of these on every valve.
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Originally Posted by 2xLS1
One problem I see is the high lift and rpms like I said earlier, and people just throwing springs on the heads without checking the installed height. Who actually sets their spring height? Isn't Crane saying installed height effects the harmonics in the spring? Take a look at the broken Crane spring thread. People are saying use this shim or that shim when the only way to know what, if any shim you need it to use one of these on every valve.
Bought one for myself...money well spent
though stock valvespring heights are typically consistant so a "guesstimate" shim pack is usually sufficient.
Once you go with different valves, etc, then it becomes crucial to measure EVERY spring...my heads had .010 variance...
#15
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To my way of thinking, the rather small O.D. of the spring and the high lifts and RPM's is the issue. It's like sending a boy out to do a man's job. Larger O.D. springs would not be nearly as stressed. The only real issue is clearance at the underside of the rocker and the size of the spring seat pad!
#16
6600 rpm clutch dump of death Administrator
Originally Posted by 2xLS1
#17
one thing that has not been mentioned is valve weight. as you all know the ls-6 has hollow stems. allows the increase in rpm's. we have light weight 2.100 intakes at 88 grams. i don't have the ls-1 weight at hand but it may be over 100 grams. also in reference to the big block it has much larger dia. springs over my 40 years of building engines i have seen them break springs. many of you are daily driving cars with hp that 5 or 6 years ago was only found in race cars. the one lap car that we were involved in two years ago ran to 7000 rpm over the 4000 mile distance. it had titainum intake and exhaust as well as a larger diameter spring.
myron c
myron c
#20
6600 rpm clutch dump of death Administrator
I'm sleepy, but tomorrow, I'll see if I can find the spreadsheet TEA did with all the valve weights...
EDIT:
Here it is..
http://www.totalengineairflow.com/te...ainweights.php
EDIT:
Here it is..
http://www.totalengineairflow.com/te...ainweights.php