Does anyone know what the stock Stage I,II Max Wedge valve spring specs are? I'm putting together a stock '63 engine with a stock cam and I don't have valve springs yet. Trying to figure out what to put in it.

Thanks, Jack

Original 413/426 MW specs.

Interesting that the outer spring open height is listed at .500 from the closed height, while the inner is only at .430 from the closed height.

On the MW head, the inner spring doesn't sit on the same seat as the outer, there is a raised seat for the inner.

That’s correct........ but if you have a cam with say .500 lift....... the inner step and outer step on the retainer both move .500”......... and both inner and outer springs get compressed the same amount.

Also, the diameters listed look to be “inside” diameters.

I remember NHRA using 125 lbs. on the installed height and 300 lbs at .500 lift when I use to race my 1963 415 HP M.W. stocker before NHRA did away with using the stock factory spring loads specs.in their tear downs It was the same spec on both M.W. motors in 1963, not the same in 1964. I'm not sure about the 1962 M.W. specs. either
On any solid lifter cam motor I build now I set the valve springs up on I use from 140 to 160 lbs. on the seats and from 325 to 375 Lbs. opened at what ever the max lift at the valves are minus the lash Make sure you have between .060 to .100 clearances between coil bind and the valve seals to the keepers or retainers, which ever one is the closest also

This is exactly what I was looking for! Thank you!

Unless I’m missing something, this doesn’t make sense to me either!

Do you remember what spring you used?

I don't remember that far back but I'm going to say I reused the stock ones with shims
Later I may have used new stock street hemi outer springs from my local Dodge dealer with Isky inners, maybe
Now I would use a set from PAC or Isky or who ever you like to use.
I've had a 1000 Lb.valve spring tester since 1972 or so, NHRA would use the same brand Rimac tester that I had so as long as it wasn't more pressure on the heads I was good, I don't remember them ever measuring the O.D. or the I.D of the springs back then

tt

Thanks for the info man!

i found this from a june '71 bulletin #2. outer: 110lb @ 1.83", 276lb @ 1.36"

inner: 31.5lb @ 1.56, 50lb @ 1.13"

cab, do you remember these old yellow springs? sure wish i'd kept some of that stuff.

if using an old 300/308-.520" lift grind you don't need a bunch of spring. it's a pretty gentle profile. the issue will be using a stock steel retainer with a more modern 1.50 and larger diameter spring.

Looking at the specs from a John K’s bulletin......

They are specs given so someone can test the springs and verify they are still serviceable...... they don’t necessarily tell you what the installed operating loads are.

Unless there is something peculiar to the MW retainer, the typical BB retainer has a nominal .080” step, and the step on the head is usually .100-.120”........ so the inner spring installed height would be a nominal .200” shorter than the outer spring....... if no shims are used on the outer spring.

Calculating the rate from the specs provided, and averaging the mid-point between the hi and low specs....... the outer springs are 342lbs/in, and the inners are 109lbs/in. 451lbs/in for the two combined.

Installed at 1.86 outer/1.66 inner, the loads would be a nominal: 114 closed/340@.500 lift.

For comparison, the MP 933 Hemi spring is rated at 109@1.900, 432lbs/in....... so installed at the same 1.86 as the example above, it would be 126@1.86 and 342@.500 lift.

Unless it’s a numbers matching, nut and bolt type of restoration...... I wouldn’t bother trying to duplicate that OE spring arrangement.
When refurbishing and upgrading OE heads, my preference is to machine down the inner step on the heads and use either a spring cup or inner spring seat , and a spring that’s currently in production and easily replaced if necessary.