Internet score: Upgrading STOCK Vortecs

[Billla]

I was searching on Vortec information and came across this Vortec article from CarCraft. The article below provides details, but it's possible to upgrade stock Vortec heads to allow .550 lift with no machining using CompCams "beehive" springs. Upgrade cost of about $275 for a total cost of $835 for a pair - assuming you do your own assembly. SDPC sells a machined and spring-upgraded set using GM ZZ4/LT1 "HOTCAM" springs good for .525 lift for about $700. I have NOT personally done this swap.

Springs
Comp Cams 26915 $186 OR Comp Cams 26918 $186
Retainer, steel
Comp Cams 787-16 $59
Keepers, 7-degree
Comp Cams 648-16 $28

Dual spring kit
Comp Cams 986-16 $85
Retainers for 986 spring
Comp Cams 740-16 $60
Keepers, 10-degree
Comp Cams 611-16 $26

http://www.carcraft.com/techarticles...ade/index.html

http://www.sdpc2000.com/catalog/2172...ng-Upgrade.htm

[rage'nrat638]

I AM REALLY LIKING THESE VORTECS
i just drilled the stream holes yesterday..have a stud boss cutter on the way to install screw in studs..
comp cam makes a spring seat cutter for use with a hand drill. for up grading springs as well.. just trying to make sure i get the correct tools (cutters)

maybe you can help me out bill

from what i understand what kills the lift on the vortec heads is the valve stem height..

so two cutters are needed...

one that cuts the spring seat..
one that cuts the seal area...
is this correct?

i will go read your new tech articals now thanks bill

http://www.amazon.com/COMP-Cams-4718...U&s=automotive

[Billla]

Originally Posted by rage'nrat638

from what i understand what kills the lift on the vortec heads is the valve stem height..

so two cutters are needed...

one that cuts the spring seat..
one that cuts the seal area...
is this correct?

Nice job on the steam holes - the angle looks perfect.

Yep, this is correct - they use the guide boss as a locator for the spring and for the very tall stock valve seal. I believe Goodson (www.goodson.com) makes a cutter that can do BOTH cuts in one operation, but I haven't looked at it yet. Cutting the valve boss is something I wouldn't tackle at home unless you have the setup to do it...and the cutters/pilots ain't cheap :/

[shortbed70]

I remember that article. So basicly you can take stock un modified vortec heads and use the behive springs and run more lift RIGHT? I am looking for a set for my older block and have a 480 lift cam. I like the flow and the smaller chamber will give more compression from 76cc. Jegs told a friend of mine you have to drill holes for colling for a 350 block, whats that all about? I didn't think 350's needed steam holes?

[Billla]

Originally Posted by shortbed70

I remember that article. So basicly you can take stock un modified vortec heads and use the behive springs and run more lift RIGHT? I am looking for a set for my older block and have a 480 lift cam. I like the flow and the smaller chamber will give more compression from 76cc. Jegs told a friend of mine you have to drill holes for colling for a 350 block, whats that all about? I didn't think 350's needed steam holes?

That seems to be the deal. I'm going to pick up a set of heads next month and give it a shot; I also want to try some serious porting work on them to see what can be had. Note that it's more expensive to do the spring swap than it is to buy upgraded Vortecs from SDPC or Summit...but you end up with the CompCam "beehives", which are great springs.

You do not need additional holes for cooling on a 350; that's only for the 400 "steam holes" due to the siamesed bores.

[rage'nrat638]

bought those items on ebay and saved a few bucks.

springs

http://cgi.ebay.com/ebaymotors/COMP-...spagenameZWD1V

retainers and locks

http://cgi.ebay.com/ebaymotors/COMP-...spagenameZWD1V


http://cgi.ebay.com/ebaymotors/COMP-...QQcmdZViewItem

235.00 for every thing

seals i picked up at napa 23.00 for 16 total nice seals

[rage'nrat638]

a couple of the goods

[rage'nrat638]

what the hay.. a couple more

[vk_chevy]

ragenrat, have you measured to see what you have for clearance between the bottom of the spring retainer and the top of the valve seal? I wonder how the difference in clearance is made up? Thinner retainer that sits up higher on the valve stem?

Also, there appears to be another solution that doesn't require machining, crane spring kit 10309-1 includes all needed parts to allow vortec heads .550 lift and is a bit cheaper too, kit runs at summit for 169, there is a quick write up a the bottom of this page on this link http://www.gilbertchevy.com/frame.ht...ds/Vortec.html

who wants to try out the crane solution?

[Bishops Trucks]

Nice work and great advice.

[rage'nrat638]

Originally Posted by vk_chevy

ragenrat, have you measured to see what you have for clearance between the bottom of the spring retainer and the top of the valve seal? I wonder how the difference in clearance is made up? Thinner retainer that sits up higher on the valve stem?

Also, there appears to be another solution that doesn't require machining, crane spring kit 10309-1 includes all needed parts to allow vortec heads .550 lift and is a bit cheaper too, kit runs at summit for 169, there is a quick write up a the bottom of this page on this link http://www.gilbertchevy.com/frame.ht...ds/Vortec.html

who wants to try out the crane solution?

well heres a picture of the retainers that were on the vortec heads i have (stock) ? verses the LS1 retainers this distance will add to the lift factor 5/16" of a inch seems to be the difference

[rage'nrat638]

hey i got my new spring compressor.. off ebay for 20.00 shipped.. after two weeks

this thing makes short work of changing springs

[vk_chevy]

Originally Posted by rage'nrat638

well heres a picture of the retainers that were on the vortec heads i have (stock) ? verses the LS1 retainers this distance will add to the lift factor 5/16" of a inch seems to be the difference

Thanks for that picture, as the saying goes "a picture is worth a thousand words"

Now get it why you can drop in a new set of retainers/springs/keeprs/locks and be set up for a more aggressive cam.

[Hog]

The retainers you used are the incorrect ones for the iron Vortec heads. You are using retainers for the different sized valves teh GEN3 engines are running(774-16), and not the 11/32" 787-16 you should be running for teh GEN 1 Vortec heads.

I dont know what will happen if anything, but the incorrect retainer was used.
peace
Hog

[rage'nrat638]

Originally Posted by Hog

The retainers you used are the incorrect ones for the iron Vortec heads. You are using retainers for the different sized valves teh GEN3 engines are running(774-16), and not the 11/32" 787-16 you should be running for teh GEN 1 Vortec heads.

I dont know what will happen if anything, but the incorrect retainer was used.
peace
Hog

your correct, the retainers used are for gen3 valves thats the whole point of the spring upgrade.

welcome to the board

[grayw0lf]

Is there any type of valve alignment or anything else like that to do when changing valve springs? Or will the valve be centered by the shape of the valve seat?

[RACINJASON22]

I'm not exactly sure about your question graywOlf. But if your asking about the vale being centered in the valve pocket the valve guide (internal) keeps the valve centered in the head.

[Troy-Built]

Another thing to keep in mind is the self aligning rockers that were used on these from the factory. You still have to use them unless you go to screw in studs.

[swb85]

Originally Posted by Hog

The retainers you used are the incorrect ones for the iron Vortec heads. You are using retainers for the different sized valves teh GEN3 engines are running(774-16), and not the 11/32" 787-16 you should be running for teh GEN 1 Vortec heads.

I dont know what will happen if anything, but the incorrect retainer was used.
peace
Hog

I just double checked on this and you are correct. There are two different retainers for use with comp 918 beehive valvesprings. The 774-16 is listed for use with gen3 LS family engines. The 787-16 is the retainer that should be used on non-LS1 applications when using the beehive springs. Glad you posted this and I caught it before ordering mine. Wonder what the difference is in the retainers and what will happen (if anything) if the incorrect retainer is used??

[rage'nrat638]

OK GUY'S I JUST SENT A E-MAIL TO CAR CRAFT...
on this topic, posted the link to this very thread, so we can get to the bottom of this retainer deal. i will let you guy's know as soon as i do.
i have not yet installed my heads. and want this to be right.
your pal mark

[jimfulco]

The difference is in the valve stem diameters. They may look close, but they're not the same. The GM LS retainer/keepers won't fit properly on a Gen-1 valve stem, so CC made some that will.

[Hog]

Glad I could be of some help. Can you guys keep us informed as to what CC response is please.

i have a 1997 reg cab shortbox, Vortec 350 truck and I would like to install a camshaft with more lift to compliment my new intake manifold with 29 pph EV6 injectors.

Here is a pic of the intake as shipped from GM before mercruiser sprays it red.
http://www.sfatek.com/images/efi.jpg
I did the install myself. All teh marine intaek components cost over $300 US, but I bought my intake used and did teh install including PCM tuning for $995US. I did teh retrofit myself.

Notice theexternal fuel rails and fuel pressure regulator. No more 400 crank hp barrier with teh stock 19 pph poppets. The stock poppet injection spider was actually insid eth intake manifold on the stock L31 Vortec intake restricting flow.

If anyone wants any info on the intake manifold conversion, let me know.
Thanks for the welcome.
peace
Hog

[rage'nrat638]

well i have not heard dick from car craft.. i just ordered the supposed correct retainers . should be here in a few days pictures to follow...

[rage'nrat638]

well i have not heard anything from car craft

so i went ahead and bought the new 787-16 retainers
i will be installing these this week end.

we will see what the difference is

[Blue85]

any updates?