these valve spring dampers

[Turbo6Smackdown]

I did a search, but actually found nothing. Maybe I just suck. Oh well, anyhow, I just had my "LT1" valve springs checked, to see if they didnt have any crazy pressure (after reading richard clarks zddp thread, i started getting nervous about this install. if i wiped a lobe, Id be devastated)
I took em to Automotive Machine (a local shop with a decent buick reputation) and had em check em. I checked with you guys first, to see about installed height, and you guys said pretty much 1.72. So I walk in, tell em what I need, and he asks "What kinda pressure are you lookin for on these"... (I said "I think theyre 105's, but im not sure)
That kinda made me wonder. Why do you need to know that I thought. Is he going to not measure them, and just tell me what I want to hear after that? So after picking them up, he said "they were all +/- 5 lbs of what you specified." I see... Then, I come back here to re-read some posts, and now I keep seeing more and more "dont go too heavy, or youre going to wipe a lobe"... So is +/- 5 pounds on a 105 pound spring ok?
(the guy at the shop recommended around 90 pounds when I asked him)

Also, they have the little damper springs on the inside. Do I keep these? And whats this 'cup' I keep hearing. Some guys say they used em, some say they didnt. Do you use this 'cup' to gain a few more pounds of pressure? Or am I misinterpreting this. If these are indeed 100-105 pound springs, is there anything I can do to make em seat with a little less pressure?
Not use the cups or dampers? Tell me what to do. I plan on doing my timing chain, and changing the oil with zddp as well. What do you guys recommend?

 

[salvageV6]

I recommend comp. cam.s. 980's and no cups.

I actually tested them at 1.72" with a good force gauge.

Safe enough for my two cars and a good nights sleep most nights. :biggrin:

 

[A2000RICH]

I did a search, but actually found nothing. Maybe I just suck. Oh well, anyhow, I just had my "LT1" valve springs checked, to see if they didnt have any crazy pressure (after reading richard clarks zddp thread, i started getting nervous about this install. if i wiped a lobe, Id be devastated)
I took em to Automotive Machine (a local shop with a decent buick reputation) and had em check em. I checked with you guys first, to see about installed height, and you guys said pretty much 1.72. So I walk in, tell em what I need, and he asks "What kinda pressure are you lookin for on these"... (I said "I think theyre 105's, but im not sure)
That kinda made me wonder. Why do you need to know that I thought. Is he going to not measure them, and just tell me what I want to hear after that? So after picking them up, he said "they were all +/- 5 lbs of what you specified." I see... Then, I come back here to re-read some posts, and now I keep seeing more and more "dont go too heavy, or youre going to wipe a lobe"... So is +/- 5 pounds on a 105 pound spring ok?
(the guy at the shop recommended around 90 pounds when I asked him)

Also, they have the little damper springs on the inside. Do I keep these? And whats this 'cup' I keep hearing. Some guys say they used em, some say they didnt. Do you use this 'cup' to gain a few more pounds of pressure? Or am I misinterpreting this. If these are indeed 100-105 pound springs, is there anything I can do to make em seat with a little less pressure?
Not use the cups or dampers? Tell me what to do. I plan on doing my timing chain, and changing the oil with zddp as well. What do you guys recommend?

i have a lot of opinions on springs but one thing i know for sure about springs is that most folks must not have an accurate way to measure them------ i have bought a lot of springs and tested them to find they are not even close to what is claimed-------i have a $900 digital spring checker that is accurate to 0.01 lb and 0.001 inch as well as certified calibration springs to keep an eye on it-------i'll be glad to check your springs if you send them to me for no charge-------+/- 5 lbs is pretty bad-----a ten lb variation on a 90 lb spring???-----you need to consider the pressure with and without the damper------personally i haven't seen any GM springs with that much variation with the same part number------i would doubt the guys ability to check them correctly if thats what he says-------and seat pressure isn't everything------the pressure at full lift is just as important-------let me give you some info you might find useful------the published spec for the OEM vin-7 spring by GM depends on where you look it up-------in one book it is listed------ 74-82@1.727/175-195@1.340-----------the original part # is 1249267 and new ones out of the box read 77@1.727/185@1.340 with the damper attached which does add about 15 lbs--------and in my inventory (pretty large) they vary less than 2 lbs------here is some info good as of 6 months ago------these are not advertised specs but actual measured by me-------each pressure is @ 1.727/1.340-------GM#3911068-77/201------Gm#10212811 83/195 (with GN damper added)-------GM#10134358-101/255-------GM#3927142-103/263------TRW VS-800-106/240------TRW-VS 744-60/170(73/185 with GN damper)--------Kirban springs 100/254---------i spent a lot of time buying springs from everywhere and measuring them to find suitable replacements for the TR engine-------i dont' build racing engines------i do bone stock restorations------in my opinion the TRW 744 with your old gn dampers is right on the money and the closest of anything i have found after buying literally hundreds of springs from everyone that i could find that sold "correct" springs------next is the GM 10212811 with your dampers-------of course your installed height may vary depending on how the guy does your heads and that should be considered-------hopefully he can get it close to what its supposed to be and you will not have to do any compensation(ie compromise)..........food for thought.............RC

 

[Turbo6Smackdown]

WOW. Well there you have it lol. Thank GOD for anal people. I mean honestly, who goes thru this much trouble for valve springs lol. That post should be a sticky somewhere. So should half the stuff you write actually lol. I wish you'd open up a machine shop. You'd make tons.
Ok, so tell me this then. I read over the years, that even the stock spring pressure, was a bit too mild. Is this true for you street fighters? And my next question is, is if you found a little bit of a discrepancy in these pressures, whats my benchmark then. For example, if everyone but you, was ten pounds off (which im sure is the case) but WE were all on the same sheet of music. and everyone that found that comp's 980 springset worked great on our cars, does that mean that everyone could have potentially been running 90 pound springs on their mild rebuilds, instead of the purported 100 lbs? Meaning, that when someone actually DOES get genuine 100 pounders, and their cam fails, would that make them put up a post on here reading something like " I just replaced my springs with 100 pounders, and i wiped my factory cam" then all the rest of the guys say "well, ive been using hundred pounders for years with no problems." when they were actually using 90's. I know there is probably a shorter way to put this, but I only know how to ask questions the long way lol. sorry for the novel guys.
Another question. You read from a book. Well how do you know the method GM used, to test THEIR springs? Were they using the same methods as this engine builder was? lol. Put it this way, I'm going to send you my springs, since I KNOW I can trust you. You tell me what they are. It wont be immediate, as these arent goin in yet for a while, so gimme a little bit.
And this 'depending on installed height' business. It sounds REALLY variable. How. What do you do to make the installed height differ? Shims? Cups? If so, I'm guessing that the higher the installed height, the less pressure? Do I have that option? And these dampers, can I run them without em?

 

[A2000RICH]

thought i'd add a few more clarifications-----if you run without the damper don't forget the spring will exhibit less force---------the damper adds force to the spring since it "shims" the spring with about .040 inch where it is folded under the spring-----with the stock spring every addition of .010 (roughly 5 sheets of newsprint paper) adds a little over 3 lbs more force to the spring-------likewise every increase in valve height of .010 reduces the spring pressure by the same amount--------you can bet GM didn't put them in for fun------the purpose is not to increase spring tension, they could have just put in stronger springs that didn't need shims-----the primary reason is to damp oscillations in the spring------when springs oscillate they lose tension at certain engine speeds (not necessarily at the highest RPM's) and cause erratic valve movement and poor performance-------some springs do it in certain applications, some do not, all springs will do it with the right conditions------factors that create resonance are things such as speed of movement, cam lift and relative moving mass of each of the components in the valve train---------only testing on a particular setup/engine combo will reveal that-----------you ask how does the installed height change??-----think about it ???what happens when you have a valve job done???-------usually they grind the valve sealing surface and also grind the seat where the valve contacts-------in order to produce a new sealing surface they have to remove metal------the removal of metal causes the valve to be recessed in the chamber more and this raises the height of the valve stem if nothing else is done------remember that for every ten thousands of an inch the valve pressure reduces by a little over 3 lbs---------choose your head shop wisely-------here are some ramifications-------removing too much from the valve/seat area will change combustion chamber volume (lowers compression ratio)------it will weaken closed/open valve seat pressure-------it will change rocker angle also known as "geometry" creating different wear surfaces to already "broken-in" parts such as valve stems, rockers and push rods-------excess removal can require different push rod lenghts (shorter)----------a really first class valve job (ie expensive) would include the replacement of valves and seats so the original chamber volume and overall geometry of the valve train would remain unchanged---------but in the real world this seldom happens--------at any rate have the guy show you some head work--------here's two things i look for-------first make sure he doesn't remove too much from the head sealing surface---------every shop that works on chevvvvys and fooorrrds will do this or die--------its just in their blood and they will do it in their sleep-----------to ford or chevy guys .010 or.020 is "nothing" but to a TR its EVERYTHING----------and second check the installed valve height with a straight edge by laying it across all the valve stems---------if you can slide anything more than a piece of paper under any of the stems while the straight edge is contacting the two highest stems the valve job is junk in my opinion-------but i'm picky---------as for GM's spec my measurements are right in the middle of their spec on NOS springs so i guess they got it right (i wouldn't expect anything less)-----------i would also say that with most performance upgrades where the engine may be turning more RPM that spring upgrades (stronger) would be in order---------but this raises more issues such as cam upgrades----------stronger valve springs and higher lift cams are a recipe for failure without adequate EP additives--------i don't really mean to beat my own drum but to those that aren't believers time will tell---------when i get back to the thread on ZDDP i am going to explain the E, F, and G series oil tests for cam wear------I promise one thing that those tests aren't done with high spring pressures and high lift cams in performance engines-------think about it for a minute------how do they get a higher lift cam????--------ask a hundred car guys and most of them will say they put a bigger lobe on the cam--------not true---------they reduce the base circle so the ratio of base circle to lobe height is more--------this ratio defines the lift not the actual height of the lobe--------this reduced base circle gives even less cam wear surface and produces more wear for every engine rotation--------unless you are a "stock freak" like me the smart money is on roller cams especially if you are going to use modern oil without additional ZDDP............................RC

 

[waddell87]

wow thank gawd I have a print button. This is good stuff! thanks I get into arguments with my mechanic friends(I'm not one) all the time. I love logic and common sense, it makes the world go round. :biggrin:

 

[Turbo6Smackdown]

Ok so these 'dampers' are vibrational dampers then. I'm takin it the stock oem's have em too by the way you typed it. So I'm guessing you like to see me leave em in eh? If thats what you suggest, then thats what I'm going to do. So after you measure em, we'll see the REAL deal as to their pressure. After all this technical research and studying, what do you suggest for pressure then Mr. Clark? My engine is stock, with only the mods you see in my signature. I will be eventually adding a maf translator with extender chip, injectors, and better exhaust sometime in the future. I rarely have time to drive my car, (about once a month maybe) and when I do drive it, I like to race it whenever I can. What do you suggest.
Though, when wiping a lobe, isnt it the lifters, that get pressed onto the lobes too hard? Dont roller lifters help prevent lobe wiping? Why are roller cams better. I thought it was the lifters that produce excess wear on our cams?

And how the hell do you know soo much about this stuff? I thought your business was with non car stuff? Your technical knowledge amazes me.

 

[salvageV6]

SKU: COMP Cams 980-16
Brand: Comp Cams
COMP Cams 1.230" SINGLE OUTER VALVE SPRINGS with DAMPER #980-16 (SET OF 16) Use with: #728-16 Titanium Retainers #742-16, 750-16 Steel Retainers More details...
Price: $42.88

Damper is built in to the CC980's you don't need the stockers.

Right force too if you consider mine were tested on a many thousands of dollars Instron force machine.

The dead stockers, and the CC980's, and the Kirbans set I tested varied more than 2 pounds per lot, a lot more. And the Kirbans were too high for my liking.

I had a set of 16 CC980's so I tossed out the highs and lows and made a matched set.

No valve jobs here just spring replacements for the dead stockers.

 

[A2000RICH]

Ok so these 'dampers' are vibrational dampers then. I'm takin it the stock oem's have em too by the way you typed it. So I'm guessing you like to see me leave em in eh? If thats what you suggest, then thats what I'm going to do. So after you measure em, we'll see the REAL deal as to their pressure. After all this technical research and studying, what do you suggest for pressure then Mr. Clark? My engine is stock, with only the mods you see in my signature. I will be eventually adding a maf translator with extender chip, injectors, and better exhaust sometime in the future. I rarely have time to drive my car, (about once a month maybe) and when I do drive it, I like to race it whenever I can. What do you suggest.
Though, when wiping a lobe, isnt it the lifters, that get pressed onto the lobes too hard? Dont roller lifters help prevent lobe wiping? Why are roller cams better. I thought it was the lifters that produce excess wear on our cams?

And how the hell do you know soo much about this stuff? I thought your business was with non car stuff? Your technical knowledge amazes me.

stock engines all had dampers-----you could order the springs from GM with #25517605 or without #1249267 them but they are necessary with the stock springs since they need the shim afforded by the damper to have proper tension---------i'm certainly not a performance expert so you should ask some of the racers but i will tell you that in the one car that i have modified for a little more gofast i have raised the seat pressure a little to augment a little more cam lift--------you want to prevent valve float at higher RPM's-------but i'm the wrong one to ask if its not a stocker----------it is the lifters that rub the cam but they both suffer wear------roller lifters do a lot to alleviate this problem since they roll instead of rub the cam lobe-------my business isn't car related but my hobby is restoring and working on GN's-------i have several dozen of them and a rather large shop to do it in-------i share the shop and equipment with my friends that have TR's and always have friends around to work on their cars-------this weekend i had one TA and two GN's visiting the shop--------one Gn tweeking on the dyno, and the other two doing tranny work--------after doing this seriously for nearly 20 years you sort of get the hang of it.................RC

 

[Turbo6Smackdown]

I see. Thanks.
And I also see that you have quite a hang of it lol. (i didnt know you had been doing it for so long) Do you work with dennis kirban at all? Is he still into it like you are?

And salvagev6... you typed all that, and mentioned an expensive testing machine, but still no result OF that testing machine. so what was the pressure lol?

 

[Turbo6Smackdown]

stock engines all had dampers-----you could order the springs from GM with #25517605 or without #1249267 them but they are necessary with the stock springs since they need the shim afforded by the damper to have proper tension---------i'm certainly not a performance expert so you should ask some of the racers but i will tell you that in the one car that i have modified for a little more gofast i have raised the seat pressure a little to....

What shims..mine dont have any 'shims'... Are these springs missing something?

 

[A2000RICH]

What shims..mine dont have any 'shims'... Are these springs missing something?

i think we have a miscommunication---------LT1 dampers look like an internal spring if i remember correctly-------they are different than TR dampers-------look closely at the spring damper from a turbo regal-----notice the little tabs that fold under the spring when they are in place-------that tab is about .040 thick and raises the spring just like a spacer since the spring sits on it------------if you are using LT1 springs i can already tell you what they read--------give me the GM # of what you have---------i think the iron heads used different springs than the aluminum but i can't remember for sure--------i have em all on file..................RC

 

[Turbo6Smackdown]

I dont have any part numbers :frown: I got em from the local turbo regal speed shop, when I said "hey, get me some LT1 springs"
Next week, he handed me a clear bag of 12 springs. :redface:
theyre a dark bronzeish brown, with a matte black flat spring inserted inside of it. the spring goes all the way down to one end, but stops about a quarter inch short of the other. engine builder told me they were "all within about 5 pounds of a hundred and five" lol. do these sound familiar?

 

[salvageV6]

Send them to Mr. Clark to be tested.

I would trust his results over someone who knew what numbers to give ya.

A bag of springs with no part number should be retested for sure.

Here's my numbers I hope they line up on the page, otherwise you will need a decoder ring. :biggrin:

Valve Spring Tests

Number Type 1.727”

1 My Stock Original 112k 64.9
2 “ “ 67.5
3 “ “ 64.5
4 “ “ 62.5

1 Comp. Cams. 980’s 80.4
2 82.9
3 76.1
4 80.4
5 81.0
6 80.2
7 77.6
8 79.5
9 81.3
10 81.0
11 77.5
12 75.2
13 81.1
14 82.1
15 82.8
16 81.9

 

[salvageV6]

The set of Kirbans LT1's I tested were from 98.1 to 102.6 with most being around 101.

 

[Turbo6Smackdown]

thats an average of 75.025 with a spread of 7.6 pounds
is that right?

 

[salvageV6]

No.

Disregard the old worn out stockers I tested which were dead, they are listed first just for comparison.

Just use the comp. cams. data and toss out anything that strays from 80lbs. since I only used 12 out of the 16 here in the set.

About a 5 pound spread centered around 80lbs.

The dead stockers were about 15lbs. low out of spec.

Comp. Cams. 980’s

1 80.4
2 82.9
3 76.1
4 80.4
5 81.0
6 80.2
7 77.6
8 79.5
9 81.3
10 81.0
11 77.5
12 75.2
13 81.1
14 82.1
15 82.8
16 81.9

 

[Turbo6Smackdown]

i did. that was the data i used

 

[salvageV6]

How did you get an average of 75.025 when NONE of the springs tested at or below that value?

75.2 is the lowest number out of the 16.

Actually I used the higher springs and dropped the 4 lowest values since they lose a bit of force under use and over time.

Recheck that math and get back to me on the average force. :smile:

 

[A2000RICH]

The set of Kirbans LT1's I tested were from 98.1 to 102.6 with most being around 101.

my average of three sets of kirban springs was 100/254 @ 1.727/1.340------years ago i put them in about 10 of my cars over a period of several years but eventually stopped as i started to consider the oil situation------the more i thought about it the more unsettled i got------it wasn't the 100 closed pressure that scared me as much as the 254 open pressure-------thats what sent me on a search for an ideal replacement spring............RC