Hey my vortec heads are about to encounter some serious work and I need to know what to buy since I'm still learning. Here's what I know I need.


The guides are going to be cut for comp 987 dual valve springs, (Specs- O.d 1.430/ i.d .697) (121@1.800 installed seat load) (Open load 388@1.200) (Coil Bind 1.150) (Rate Lbs/In. 1.150) (Titanium Retainer 730) (Steel Retainer 740) (Shims 4754)

So i'm going to purchase those valvesprings. Now after I put them in the cart, what about locks,retainers, and spring cups. Should I purchase any of these? Whats going on here is I'm going to take 1 of my heads to this machine shop (the heads still have the stock springs and valves on it ocmplete) and see if I can get an installed height of 1.8 with a stock length valve. If not then i'll just get a longer valve. But all in all i'm getting new int/exhaust valves anyway.

Also i'm getting my stock studs pulled out, then milled & drilled & tapped for screw-in studs. Is there a place I could buy just screw in studs for my machinist?

Someone told me "Teflon valve guide seals" whats that for?

I only have like 300$ to spend right now so i'll deal with the intake/exhaust valves, the 1.6 roller rockers, lifters and the pushrods next week or so.

I'm also thinking of some port work or just the blending of the bowl area. He's also going to open the push rod holes to 1/2".


Only really asked about 5 questions Lets stick to valve train

 

I'm in the process of installing vortec heads also & I'm running the 986 springs. They're similar to yours. As far as the Teflon valve guide seals, they install at the top of your valve guide & prevent oil from seeping through & going into the combustion chamber through the inside of the valve guides. I attached a pic of the ones that I am using & be aware that your will also have to machine the valve guide to fit these. I think the guide has to be cut down to .530" to fit but I'll double check later.

Anthony

 

As far as the screw in studs go, any speed shop should be able to get you some. Comp Cams & ARP are just a few companies off the top of my head that you can get them from. Also, are you going to run the stock self-aligning type rocker arm or go with a non self-aligning rocker arm. If you go with the latter, you need to purchase guideplates also. Also, if you do go with the guideplates, make sure your machinist shaves the rocker stud boss down to make up for the extra height the guideplates create when the screw in studs are installed afterwards. I hope this all makes sense. If not I'll try & elaborate better later.

 

Don't use the teflon ones. They're "old school." I've used them myself many times in the past and they work, but not as well as the newer style seals. The Vortecs come with the "good guy" seals on them already but you may not be able to keep using them once the guides are cut to clear your chosen springs. If you can keep using them, do so (and note they are specific to intake/exhaust placement). If not, you can get the same kind of seals but to fit on a smaller diameter guide boss- they are available in .530" and .500." Look to your machine shop to recommend what will work since they're the ones goign to be cutting the guides and seats.

Regarding the spring seats..... I haven't done exactly what you're doing but similar things a couple times now.

You'll be close to 1.80 just cutting the spring seats and using the matching (larger diameter) retainers your springs will require. I have found that Vortec spring seats used with typical stock old-style 1.25" retainers (NOT the retainers that comes stock on Vortecs- older style like would come on a stock 80s vintage head) will get you right around 1.70-1.75" installed height. That's just FYI as a point of reference.

The larger diameter retainers you will be using typically raise installed height by about .050 just by themselves vs. stock (early style) 1.25" retainers. And your machine shop is going to have to cut the spring pockets deeper into the head by maybe .050 at the most to have "meat" for the larger diameter spring to sit flat against anyway (stock Vortec spring seats almost sit up on a plateau if you look at them).

Add all this up and you should be CLOSE to 1.80 with stock length valves. If anything, wider is better so you can then use some shims to bring back to perfect installed height spec.

IF YOU FIND IT DOESN'T QUITE MAKE IT..... you can buy valve locks that are +.050" installed height. This will open it up some more for you if you find it comes in slightly under 1.80 after all the machine work is done.

If you've never felt the need to lay out $80 for a half decent height mic you might want to consider that purchase at this time. I set up ALL my own heads and valve spring installed height is THE CRITICAL SPEC to get right. AND having adequate retainer to guide clearance (with the seals on!)- typically no less than .025" more than you cam's maximum theoretical valve lift, .050" clearance preferred (keeping in mind your rocker arm ratio, too!).

 

Anthony are you referring to the valve guide seal area that has to be cut down for these teflon seals ? Cause if not then i know your referring to the guides for the valvesprings (which i know need work, the machinist will get her) I just went out and looked at these seals.. I get a better picture now of what they do, thanks for clearing that up. I see their not that expensive only
24$ at summit. I know i'm getting replacement size valves which are 11/32 but I dont understand this

Valve Stem Seals, Teflon, Positive Stop, .531 in. Guide, 11/ 32 in. Valve Stem

Valve Stem Seals, Teflon, Positive Stop, .500 in. Guide, 11/ 32 in. Valve Stem

see the .531 and the .500 in. Anyone know which one it is I need please hit me up on here ok now next reply pswew lol

 

Also acescarrsRS i don't want to brainwash my head with too much stuff that i forget. So i'll talk about the rockers after i get this part squared out. Know what I mean. Cause i have to research on that stuff also. I just didn't know what size stud to go with? I guess it dont matter? I duno

 

Damon- Most of what you talked about is what i learned on a previous post , this is why i picked one just for this lol oh well its cool thanks for the help tonz! But as for the thickness of the retainer I totally understand. What I don't understand is how i'm looking in summit right now and they dont show the thickness of the retainer itsself. Only the springs Diameter and the stems thickness. What you talken about?


Also as for the stem seals, I'll just see what the machinist suggest thanks once again for the help guys

 

The "thickness" of the retainer? Now I don't know what YOU are talking about. When did I bring up retainer thickness? It's as thick as it needs to be to hold the spring's pressure and no thicker. Other than that who cares how thick it is?

Perhaps you could copy and paste into a quote the part of what I wrote that is confusing you.

 

you right sorry, no time for sleep will do this to you lol. But why don't i just get a retainer matched for my valvespring out of summit?