NewbVetteGuy

So is there a way to calculate the spring rate from the available specs on Jegs.com or should I email jegs and explicitly ask this question?


Adam

NewbVetteGuy

On the spring height micrometers: it seems like you have to buy them based upon the retainer diameter so I can either choose to buy one that works with beehive springs and their small retainers or the standard / double spring sized retainers.

There's no way I'm buying 2 of these so I guess I need to be able to estimate whether my current springs shimmed 0.015" are going to work or not; I'm guessing not.


Adam

HeadsU.P.

Spring is removed. Just use your mic, retainer, splitlocks and maybe shims. Its a clever little tool to have. Around $40 on EBay.

NewbVetteGuy

I'm not sure what you're referring to here; the quote feature is useful.

What's this "mic" you're talking about? To me, "mic" means "microphone".

Same question for "splitlocks" -never heard that term before; are you referring to the valve locks / "keepers"?

[Edit] Ok, i think you're talking about the valve micrometer tool ("mic") and are saying that you remove the spring, then put the micrometer over the valve stem, and start raising it up until it holds up the retainer with the valve locks installed and you can't open it any more- then whatever the reading is on the micrometer says, is your installed height. ---Took me a while; too many new terms too rapidly.

Adam

HeadsU.P.

Different terms from different aged people I guess. Keepers have always been splitlocks to me. They Lock & they Split, get it?
Rotators have always been retainers.
"Mics" are short for micrometers.
I don't remember "mics" coming in an assortment of diameters but they are purchased according to spring height anticipated use.

HeadsU.P.

Starting at cyl #1, exhaust valve, work your way down the head and record the height of each and every valve. For example #1E, #1 Int, #3 I, #3 E and so on. Write it down. Find the lowest recorded number and match all the rest to that one.

NewbVetteGuy

I don't comprehend how this is possible; if the height of the valves are all the same and the keeper grooves are all the same height how can the installed height vary from valve to valve? -Is it just that when the valve pockets were machined they were machined to different depths? -IF so that seems completely unacceptable and I can't believe such a practice is tolerated.

-If that is the problem, what is the fix?


Adam

NewbVetteGuy

See the previous question; how is it possible for the installed heights to vary?

Find the lowest recorded # - that would be the shortest installed height aka the least deep spring pocket? -How can you match the others to that one? Using shims?
Can anyone refer me to a good book that covers this stuff?


Adam

NewbVetteGuy

Thanks for that; the micrometers seem like they can only be used with certain diameters of retainers; there are different valve spring micrometers sold for standard and beehive springs.


See Proform parts #66902 1.600-2.200" standard retainers; and #67390 1.600-2.200" beehive retainers.

https://www.ebay.com/itm/Proform-669...!US!-1&vxp=mtr

https://www.ebay.com/itm/Proform-673...!US!-1&vxp=mtr

Adam

HeadsU.P.

Any varience in height would come from a valve a smidge longer (not likely) or a valve seat grind down a pinch more, who knows. Only talking a few ten thousandths here.
Summit sells shim kits. I believe they come 32 or 48 in a kit maybe? of assorted thicknesses. In some cases you will double up on some.

NewbVetteGuy

Awesome! I think I learned something again today; thanks for dealing with clueless me.

I'm going to buy a regular non-beehive version because I currently have retainers and valve locks for a non-beehive spring and this measurement won't vary depending upon what retainers I have.

Anyone see anything wrong with the Proform 66902?



Adam

HeadsU.P.

Just a quick note on Mics. Customers agreed that the black units are much easier to read at an awkward position sometimes, than the shiney aluminum units.

REELAV8R

A beehive mic will work on regular spring head but you have to turn it upside down to use it and be able to read upside down.

Vid on how to use one. Not sure she knows what she's talking about but you get the gist.


The valve pockets are milled different depths. At least that is what I found on the heads I have had.

Shims are .015 or .030 or .060. To get in between numbers you combine shims. IE. to get .045 you have one .030 and one .015 shim.

TCracingCA

If you are going for a new engine after some usage!

I would swap swap out the 1.6 rockers for some Steel with roller 1.5s! If you make the switch, then I would see if there is room to shim up the springs, for a hair more pressure! The Chromoly retainers you ain’t going to worry at only a 6500 rpm! Redline! Those would be more than adequate for your needs! I have tool steel and titanium on my engines, but a good stout chromoly for your level is fine!

gkull

TCracing. Back in the first posts Adam aquired heads with 130 closed and he was going to use lighter retainers for higher rpm valve control

He wants to use springs that came on the new heads

NewbVetteGuy

Kind of. I want to explore whether the springs that came on the new heads can be made to work or not; half of the reason I want to answer the question is just to learn how to calculate such a thing.

I don't mind buying the PAC springs that Mike Jones recommended for me to buy. I've got a pretty embarrassing amount of money in this build (for me anyway) and to have the whole thing blow up because I failed to install appropriate springs would be really dumb and is really something I'm just not willing to chance. (Murphy stalks me and almost always finds me.)



Now on that front: Jegs got back to me and the spring rate is 328 lbs / inch so 328 * 0.015" = almost 5 extra lbs. So shimming the sprinngs the max that I can shim them gets me to only 135 lbs closed -which would be fine if I were going with lighter weight beehives, but for these heavy double springs isn't going to cut it.


I'd rather go with the 0.650" max lift, higher pressure springs so they last a bit longer, too and even when the springs start to lose pressure I'm still in the safe zone.


This is theoretically my first and only engine build ever so I'd just assume do everything "by-the-book".



Adam

NewbVetteGuy

So just to fully finish this up and put most of the relevant information in a single post:


My heads came with 1.440" OD dual springs, with a max lift 0.600"; 135# seat pressure; 340# open pressure.

I have an aggressive hydraulic roller cam that with my 1.6 ratio RRs will hit 0.600" of lift on the intake. My springs give me 0.075" of extra room between my max lift and spring bind. The max shim I can use to increase the spring pressure is 0.015" which will increase both the open and closed pressure of my springs to 140# closed; 345# open.

Mike Jones, my cam guy recommended the following spring rates for 6,300 RPM with standard steel retainers:
#1 Traditional Double-Spring: 155 lbs closed; 435 lbs open --The closed rate isn't terribly far off and going with lighter retainers could help at a bit and make this acceptable.

#2 Beehive Springs: 145# open; 358# open

15 lbs short on closed pressure; 100 on open pressures; I'm going to have to pull out my wallet to solve this one.



Adam

REELAV8R

I would tend to agree 135 on the seat is a bit low, especially considering the weight and lift intensity of the intake valve.

gkull

What is your installed height presently? I could figure out some dual spring options and where to order along with prices for 10 degree and retainers

#2 beehive........ Beehive springs have design advantages that don't require as much spring# to control the valves compared to normal dual springs.

NewbVetteGuy

I believe my installed height is 1.800"; but I don't have a spring micrometer yet to measure actual. Estimated is definitely 1.800".


Adam