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Valve springs for Vortec heads

13K views 26 replies 7 participants last post by  0trbo4myCHEVUICK 
#1 ·
Hello, here is a link to the original post about me discovering valve seal bits and inner dampner pieces under my valve covers.

http://www.hotrodders.com/forum/some-debris-drain-plug-magnet-379282-3.html

The truck sat in a shop for over a week only for the guy to call me telling me he quoted me wrong by over double and it was going to be 500+ $ to replace valve seals.

I wen't ahead and drove my truck out of there.


Now i'm pretty lost as to what to do, I have myself convinced that this was not an issue caused by valve float or loft from over revving.

I believe these were incorrect springs for my heads and the inner dampners broke from hitting the valve guide boss then the broken pieces tore up my seals.
Specs 135 lbs. @ 1.750, 325 lbs @ 1.200

Springs are 1.250 diameter



I am trying to find the correct parts for my application, I have a voodoo hyd roller cam in my engine
Advertised Duration (Int/Exh): 270/278
Duration @ .050 (Int/Exh): 219/227
Gross Valve Lift (Int/Exh): .515/.530
LSA/ICL: 112/106
Valve Lash (Int/Exh): Hyd/Hyd
RPM Range: 1800-6000




Could someone please point me in the right direction for some springs, keepers and retainers that will work for me and my vortec heads?

I assume I could simply remove the inner dampner from my current springs, replace the seals and then maybe be back on the road but I don't want to cut any corners.


Here is the original sale ad for the vortecs, they were supposed to be ready for a 600+ lift cam.
Small Block Chevy Vortec

Racing Heads Custom

Head Castings # 906

Cut to 59CC Chambers

Never been used since built.



Heads have 1.94 Intake Valves

1.5 Exhaust Valves

All Stainless Steel 1 piece Swirled Polished Competition Series Valves.

Custom 3 Angle Valve Job

Cut for Positive type Valve Seals installed.

Screw In Studs & Guide Plates were installed.

New Valve Springs and Retainers, Keepers

Springs are good for 600 Lift Cam.

Specs 135 lbs. @ 1.750, 325 lbs @ 1.200

Springs are 1.250 diameter

No port work has been done to heads.

Heads have been drilled to except early 12 bolt intake manifolds.

Professionally done.
 
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#7 ·
Sounds like the heads don't have adaquate clearance between the top of the guide and the bottom of the retainer. Regardless of what they were supposed to be good for the Vortec does not accept lifts over .470 without cutting the guides down. That needs to be checked before bolting them on an engine to be sure they provide adaquate clearance with the stem seal installed. All things considered with valve spring the L31 heads work a lot better with beehive or conical spring set ups. As the small diameter spings go these with their smaller diameter retainer and ability to better resist spring surge work a lot better on the L31 head.

One assumes that with push rod guides the 1.5 rockers are NOT self guiding. that's a combination that leads to binding the push rod. Plus push rods riding in guides must be the hardened type otherwise you get high wear, galling and welding of the push rod to the guide.


Standard 12 bolt intakes often have a difficult time sealing with the taller L31 port, something else to peek into when bolting the parts together.

Bogie
 
#9 ·
I will be looking into acquiring some beehive springs for my vortecs. First I need to verify how much lift they can handle. I am thinking that they could handle the lift, but the dampeners would not clear the guide boss, but that's only a guess.

I sealed up the 12 bolt intake holes that were drilled in to the heads because yes the older style intake ports are not raised like the vortecs. Could still be used, but not optimal.
 
#8 ·
Thanks guys, I pulled the heads off today. Every single one of the dampners is broken along with most of the guides. My pistons also looked very dirty for only 1-2000 miles. I am assuming this is from the oil getting past the seals, and also the intake ports on my intake were oily so I am assuming I was sucking oil through the PCV valve.
 
#11 ·
Wow a lot to wrap up in your previous 3 posts.

Thanks guys, I pulled the heads off today. Every single one of the dampners is broken along with most of the guides. My pistons also looked very dirty for only 1-2000 miles. I am assuming this is from the oil getting past the seals, and also the intake ports on my intake were oily so I am assuming I was sucking oil through the PCV valve.

This indicates the guides were not cut for damper clearance. Any lift at the valve greater than .470 inch will for sure require milling the guide down to a low enough height to provide a minimum of .050 inch between the top of the stem seal and the bottom of the spring retainer. So yes when cutting the guide dimension also needs to be considered for the thickness of the stem seal. The use of a positive stem seal will also require machining the guide diameter to fit the inside diameter (ID) of the seal. As far as Vortec heads go you should really consider milling the guide when the lift at the valve arrives at .45 inch as there are variations between the castings.

As for oil getting past the seal certainly if the retainer hit the guide hard enough to bust them that the seal being between these places got crushed in the process and certainly couldn't make any seal after that event.

My note to you is that neither the valves, the heads, nor the springs and retainers can be trusted at this point. The heads must be tested with Magnafluxed or dye penetrant to ascertain if the part collisions caused cracking within the head castings. If there are cracks in the guide area the heads are junk. So do this before having any operations done on the head.

I will be looking into acquiring some beehive springs for my Vortecs. First I need to verify how much lift they can handle. I am thinking that they could handle the lift, but the dampeners would not clear the guide boss, but that's only a guess.

I sealed up the 12 bolt intake holes that were drilled in to the heads because yes the older style intake ports are not raised like the Vortecs. Could still be used, but not optimal.


Springs must first be able to take the lift, some math has to be done before the purchase to get into the neighborhood; then install measurements need to be made to verify the math gives the necessary result. At full valve lift the compressed spring needs to have a minimum of .050 inch between each coil. This applies not only to the outer spring but also to any dampers and inner springs. This is hard and tedious to do with nested springs. The Competition Products has a big chart in their hard catalog that dimensions springs, retainers, and locks that they sell; it is a good tool to have around when doing the basic math of what can likely fit. https://www.competitionproducts.com/inforequest.asp

Note that Beehive and conical springs are a great asset with cams that aren't crazy wild; the differential coil wind and variable diameter results in a self damping spring eliminating the need for dampers if not secondary springs in some cases. The smaller retainer has few clearance problems on L31 Vortec heads than standard retainers so milling the guide is delayed a few hundredths of an inch of lift. The smaller, thus lighter, retainer also takes some of the mass control strain off the spring allowing better control of the valve with less spring pressure; this is good for a few hundred RPM as well.

The standard intake applied to a Vortec head is always iffy; the Vortec raises the port position to where many if not most 12 bolt intakes will not hold a seal along the top and often along the bottom as well. If the heads are milled and or the block decked this seal becomes much harder to maintain through the service life even if it doesn't leak when initially installed. Vortec intakes even an inexpensive one is a better choice than risking frying the engine one fine day.


I was not aware that I am at risk for binding my pushrods. Yes the rockers are not self aligning but I thought that was the point of the guide plates?

I am running comp .080 hardened push rods.


The use of both self guiding rockers and push rod guides can bind the rocker because the self guiding rocker is going to align with the valve stem where unguided rockers via the push rod being aligned by the push rod guide are forced to align with the push rod. You will notice that often the rocker on these doesn't sit exactly over the valve stem but rather favors to one side. So when both are used the rocker is now stuck trying to satisfy both alignments.

Note that since you've had hard collisions between the retainers and guides, and possibly spring coils; there is a risk that the rockers, their studs, and the stud bosses of the head, as well as the push rod guides and push rods may have sustained damage. These things need to be carefully inspected for unusual wear, cracking/breakage or bending.

Bogie
 
#15 ·
Wow a lot to wrap up in your previous 3 posts.






My note to you is that neither the valves, the heads, nor the springs and retainers can be trusted at this point. The heads must be tested with Magnafluxed or dye penetrant to ascertain if the part collisions caused cracking within the head castings. If there are cracks in the guide area the heads are junk. So do this before having any operations done on the head.


Note that since you've had hard collisions between the retainers and guides, and possibly spring coils; there is a risk that the rockers, their studs, and the stud bosses of the head, as well as the push rod guides and push rods may have sustained damage. These things need to be carefully inspected for unusual wear, cracking/breakage or bending.

Bogie

Hopefully what occurred is the inner dampener being busted on the valve guide boss, then the dampener pieces chewing up the seals.

I was incorrect earlier on my statement about the retainers busting the guides, I meant to say seals.
 
#12 ·
Here is the original sale ad for the vortecs, they were supposed to be ready for a 600+ lift cam.

"Professionally done."

. Doesn't sound like much of a professional mechanic...


. That's why we buy our heads bare and put them together ourselves... with known good parts...


http://www.sears.com/craftsman-valve-spring-compressor/p-00947627000P


http://www.summitracing.com/parts/nal-12499224


http://www.competitionproducts.com/Stainless-Steel-Performance-Valves-Valve-Sets/products/34
.
 
#16 ·
. Doesn't sound like much of a professional mechanic...


. That's why we buy our heads bare and put them together ourselves... with known good parts...


Sears.com


http://www.summitracing.com/parts/nal-12499224


http://www.competitionproducts.com/Stainless-Steel-Performance-Valves-Valve-Sets/products/34
.


Ya not a professional by any means judging by the quality of work.
That is a nice affordable spring compressor! Now that is something I need, Along with a digital timing light!
 
#13 ·
Wow indeed! Thanks for the insightful post, you have enlightened me on some important things to look out for in future builds.

I got my heads off yesterday and ran them up to the machine shop. The inner dampener on the cheap valve springs was bashing in to the guide boss.
Every single inner dampener was busted along with most of the seals.
I have adequate retainer to seal clearance for my cam.

Machine shop is recommending I install these springs, CRANE 99845-16
http://www.summitracing.com/parts/crn-99845-16
 
#17 ·
The inner dampener on the cheap valve springs was bashing in to the guide boss.

. I suspect others have run those same springs for years on the proper application with properly set up heads... the heads look falsely advertised to me when claiming OK to .600" lift... (maybe to .500" lift would have been OK...) ... Hope you gave the seller a bad recommendation...
.
 
#14 ·
I am going to have to get my engine on a stand, pull the oil pan, and check my bearings. Hopefully I have not caused any damage to the short block from metal floating around in the oil.
Luckily I have my oil filter bypass plugged, Hopefully the filter caught anything that would cause harm.
 
#18 ·
I am kicking myself in the arse because it doesn't actually state anywhere in the ad that the heads will accept .600 lift, instead they state the SPRINGS are good for .600 lift... Which may be true according to seat and open pressure...

I am fairly certain that any size camshaft would have caused the same problem.
Vortec heads were not originally equipped with dampener springs, just a single spring due to the enlarged guide boss.

My shop guy said there is tons of retainer to seal clearance because the eBay seller did do a lot of grinding and did the right things for more valve lift on the heads but failed to install the correct spring.
 
#19 ·
Perhaps they simply forgot to grind down the O.D of the guide boss then just installed the springs and shipped them out.

I agree with you that these springs COULD have worked had the dampener been removed or the O.D of the guide boss trimmed down.

Shop guy stated they are about 40$ springs and they have success with them on low budget dirt track engines. Most of them however probably do not have vortec heads and if they do have been modified to run a dampener spring.
 
#20 ·
The GM LS6 springs that were posted in the Summit link would be a good choice for your issue, as well as only 60 bucks. This requres no spring seat machining on the Vortec head, however always check your guide to Retainer distance as stated before. You will need the comp cams 787-16 Retainers and the 7 degree locks 648-16. Also, sounds like the ebay seller did the "gheto grinding" of the retainer as well to gain more clearance.
T.J.
 
#22 ·
Oldbogie,
Not to highjack from the original OP, but thanks for the plethora of information on these Vortecs as well as other contributors. I am sure there are a lot of people using Vortec heads and have run into this situation. This should be a sticky. I will be working on a set of Vortecs soon for a project. I will be using the GM LS6 spring and comp cams 787-16, 648-16, and GM LS6 12499224 springs. I also will be using the Comp cams tool CCA-4726 to cut down the guide boss to .530”. He is my question. Do I need to run any sort of spring cups or shims under these springs? I know when I did my Ford GT 40 heads years ago I got some real nice cups from Ford Motorsport (that is what it was called back then before Ford Racing Parts). These were a real nice stout shim that had a nice lip raised at the edge where the spring settled in nicely. I know I need to shim to get the proper height, but really wondering about spring cups.
I also will be running screw in studs and guide plates as well. I will be doing this myself on my Bridgeport at home.
Thanks again.
T.J.
Parts I will be using.
GM LS6 Behive springs-- 12499224
Comp Cams Retainers-- 787-16
Comp Cams 7 degree locks -- 648-16
Comp Cams cutter -- CCA-4726 cut guide to .530”,
CCA-4732-- arbor
VTO V530 small OD valve seals
 
#25 ·
Spring cups are always needed on aluminum heads to protect the softer aluminum of the spring pocket from the hardened steel of the spring. That is in addition to adjusting the spring for working height and tension. The cup alone may be sufficient but additional shims can be used to dial everything in.

On iron heads no wear protection between the spring pocket and spring is required, however, to establish working height and tension spring cups and/or shims may be required. The Vortec head is pretty thin in some areas around the spring pocket, milling the pocket or excessive porting of the intake in that area can either immedately break through or have a thinned zone that will crack in service so caution and care needs to be taken when working in or under the spring pocket.

Bogie
 
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#24 ·
The same thing happened to me, Vortec heads advertised as .600 lift and broke the damper springs and smashed all the valve seals at .520 lift.

I ended up going with the LS6 beehive springs and 787-16 Comp retainers. Check and double check all your measurements, its not difficult with a snap T gauge and mic.

If I remember right, valve oil seal to spring retainer clearance is going to be your limiting factor, mine came in at something like .540
 
#26 ·
My builder has had some bad experiences with the COMP beehive springs, as well as some other recent comp products. That being said, I DO have comp push rods and rockers so we'll see how that goes.

I am ordering these springs for my vortecs, more than the 60$ ones listed above, but about the same price as comp beehives.
CRANE 99845-16
http://www.summitracing.com/parts/crn-99845-16
 
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