I think I just got totally screwed by the machine shop. They were SUPPOSED to machine the heads for "normal" valve springs, but instaed all they did was install guide plates and screw-in studs..........and charged me $200 for that!!!!!!!!! #@!%$#@!$!#$!#% I'm so *** damn pissed right now. Well anyways, he says now I have to order some valve springs, but since they didn't do **** to the spring seats.......what options do I have for springs? Will any 1.250inch diameter chevy spring fit? I was planning on using some .050 retainers so I could get away with .520 lift cam I'm using. This sucks. I ALWAYS, repeat ALWAYS get screwed by machine shops. **** ALL YOU MACHINE SHOP SCAMMING MOTHER ****ERS

 

200 doesn't sound bad to me for studs and guide plates, i do my own and would chage more than that. why don't you take the heads back and have the spring seats cut for bigger springs, you'll have hard time finding stock diameter springs good for .52 lift. whats a .050 retainer?

 

Crane has a drop in spring kit 10309-1 its about $145 and but their only good to around .500 lift.It might be worth it it machine the spring pocket and then you can use what ever springs you want.

 

Crane 99846 springs are good for .600 lift when installed
at the recommended 1.75" installed height.

K-motion k-700 springs are good for at least .550" lift
when installed at the recommended 1.70" installed height.

These are stock diameter springs. The inner damper may
or may not interfere with the valve guide boss on vortecs.
Depending on the specific spring. You'll only know for sure when you try them.

Just because you install some +.050" retainers, don't assume you'll now have enough clearance between the retainer and guide
seal for .520" lift. Measure it and have it machined for clearance.
Choose your springs and retainers and trial fit them, then if further machining is nessessary, Have the shop estimate the cost
in advance in writting.

There is now a dedicated cutting tool for machining down Vortec
valve guide bosses.It's available from Comp Cams.
This is a very simple operation and can be done with the right cutter in a drill. Cost should be no more than $50.
If the shop wants a lot more, order the cutter your self and do it your self with a drill.
With stock self-guided rockers (which are good for over 420hp) you don't need to use screw-in studs or guideplates.
If you have the proper "street" spring pressure and no mechanical interference and do not "valve float" the motor, the factory pressed in studs are more than adequate. It takes a lot to pull them out.

 

well, as for the screw in studs and guides, its already a done deal, so there's nothing more to say about that........however as far as the guides go...........I didn't quite understand what you said Fbird. Are you saying that I can order K-700, remove the inner damper, use .050 retainers, and NOT have to do ANY more machine work if the retainers provide enough clearance?!? I'm so confused as to how they come up with these lift limit #'s, is it the pressure or the height??? Summit carries that tool (comp part # 4716), its $45, and I called a machine shop and they quoted me $40 total for the work, but do I need to have the heads special machined with that tool just to install those $42 K-700 springs?!? Damnit, couldnt' GM just make vortecs good to .520 lift from the factories, son's of bitches.

 

What about crane's 99848, I found this note on them.......

http://64.90.9.168/cranecams/pdf/512e.pdf

 

Crane and K motions both make 1.25 springs that are supposedly good to .550. I'd get the Cranes over the K motions, I've heard bad things about the K motions breaking. They're circle track cheater springs basically.

I got the comp cams conical springs for my .540 lift with stock pockets, I wanna say Pn 946-16 but I'm not positive. they're 1.25 at the base but 1.4 something at the top. They're a little more expensive because you have to buy 1.4x retainers and locks to match, but I thought it was well worth it for the reduced stress on the springs.

 

I can see why you're having such problems by how you twist my advice. There are maybe one, or two or maybe three ways to do this job right, but you're not catching the drift. Do not remove the damper EVER!! Some springs that have the same 1.26" outside diameter, have a slightly different inside diameter. We tried a set
the other day (unknown brand) that were 1.26" dia but did interfere with the guide boss dia. when we trial fit them.
Ya learn something new every day. CHECK YOURS!
The maching operation is the same, just a different cutter.
The GM stock application was for a .400" lift cam so they make their valve guides as long as possible because it makes them
last longer in a truck, marine application. Remember these
are production stock heads, they crank out millions of 'em.
that's why they are cheap. Even after doing all and or any required modifications to get these heads ready for your street
performance application you'll still have less money in 'em than
other "performance heads". and better "Street "performance.
You need to increase the clearance between the retainer
and guide seal by .200" not .050". The +.050" retainers
cost more then the machining operation. And increase the spring installed height by+.050 not nessessairly the distance between the retainer and guide seal. The stock vortec retainer is very desireable (light weight and strong) for stock diameter (1.26")
street spring aplications. A light spring, valve retainer, rocker
combination requires less spring pressure to control valve motion.
{Light, moderate pressure valvetrain components are
better than big heavy stuff that needs more pressure to work right.} Less wear and tear.
Which .520" lift cam are you planing to use? There is more to
getting the proper spring setup than just coil bind and
diameter. The camshaft manufacture is the best source
for this information. They can recommend their best springs or
and alternative manufactures spring like K-Motion.
A fast action Hydraulic roller ( Comp Etreme Energy)will need a different spring than a mild factory roller (GM ZZ4) or hydraulic flat tappet cam.

 

Jester: I've also heard of other people having some trouble
with K-motion springs. I believe it is the K-750's (H-11 tool steel)
not the k-700 {silicone chrome) that were failing.
Or possible a bad batch. There was a bunch of motors
from one shop here, that had problems. but I use 'em and haven't heard of any problems since.

H-11 tool steel , wether Crane or Isky or K-motion is
brittle. Thats how they get so much pressure out of the same diameter, compared to other materials. You can expect more failures because of this.
The cone type Comp springs are another good way to go.