Valve Spring problem

Loriannes keeper

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08 Mustang GT convertible. Had a blinking light misfire on cylinder 2. Removed head and found broken intake spring. Ordered some new melling springs and then supposedly actual ford stock springs. Both sets of springs are shorter than the ones that came out the car. But supposedly both springs are a verified fit for the engine. Why is this?
And yes I know there's a bunch of stuff I should do while it's apart, I'm doing the required stuff, but I have not the time or money. I need the car on the road to go to work. Performance will come later.
 

Midlife Crises

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I have run 3 different sets of valve springs on my 4.6 3 valve. Stock Ford and two different sets of Comp Cams springs. All 3 sets of springs were basically the same length. The 2 valve, 3 valve and 4 valve engines do not share the same valve springs. You must be sure you purchase valve springs for the 3 valve.
Do you know if the springs that are in there now are stock?
 

Loriannes keeper

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OK after some review they may be performance Springs. How do you tell if you have a performance cam and springs.
 

JC SSP

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Might help to post the part numbers that are on the box or packaging.
 

Loriannes keeper

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Good point
Pic of springs, on left is broken spring, in middle is spring pulled out of head and right is the springs ordered. Second pic is springs ordered in there packaging.
 

Loriannes keeper

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Good point
Pic of springs, on left is broken spring, in middle is spring pulled out of head and right is the springs ordered. Second pic is springs ordered in there packaging

20260523_154232.jpg

20260523_154223.jpg
 

Midlife Crises

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The two intact strings are effectively the same length. I do not believe the broken spring is a stock Ford spring. I think it has too many coils. As far as the cams go, the stock Ford cams are a hollow steel shaft with the lobs pressed on. Aftermarket cams are machined from a solid shaft so they are one piece.
 

JC SSP

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Ok one new OEM Ford spring, one new melling but where is one old not broken spring pulled from your cylinder head? You say new ones are shorter but how do you know that?
 

Loriannes keeper

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I measured, the spring from the engine in the middle is 1 tenth of inch longer than the ordered spring. That's more than a 1/8th.
 
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