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Discussion Starter #1
Hello I’m refreshing a 289 out of a 1967 mustang fastback for a friend of the family’s. Oppon disassembling the heads I found one of the original valve springs was broken. There’s two different types of valve springs available one says “ after L-10 to L-14” and the other says “after L-14 change” I honestly have no clue what this means and I need help picking out the right springs for the engine I’m working on.
 

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I'm pretty sure the L means Level. During the life span of a certain engine many changes are made. For example, the '65 and earlier 289 heads had slotted guides for the pushrods in the head. In '66 Ford changed from slotted holes to round holes and added the "rail" rocker arms to keep the rocker centered on the valve stem. That was a L change. If the engine you're working on still has the metal tag attached to the intake manifold it will tell you which L your engine was built under.
 

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For a stock engine, I would just use some quality aftermarket springs for a mild cam, like Edelbrock #5722. I would change them all.
 

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Yes, @awhtx is correct. The "L" refers to the change level (revision number) of engine. Knowing the change level is a must if you are only replacing certain parts, particularly valve train parts like valves, rockers, springs, etc. As stated and assuming the engine has the original engine tag, you can find the change level on the engine tag. Otherwise you can identify the change level by examining the parts used when the engine was put together at the factory. That's assuming that someone already didn't tear into the engine resulting in a mish-mash of parts. Bob Mannel's Mustang and Ford Small Block V8 book is indispensable in this respect. Keep in mind, just because you are pulling a 289 out of a 67 doesn't mean that the engine was produced during the 67 model year. Also, make sure you check for the correct push rod length if doing any machining of the heads or block and/or changing any valve train components from stock.

EDIT: @Archer meredith just saw your post. Having the engine tag is a good start. Try to verify that its original to the engine just to make sure.
 

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Also, make sure you check for the correct push rod length if doing any machining of the heads or block and/or changing any valve train components from stock.
As a point of clarification, a valve spring can be changed with no impact on pushrod length.
 

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@66coupe289 I agree but I would not mix and match different spring sizes.

There was variation in stock spring sizes through the life span of the 289 which could affect performance and longevity if mixing parts from different change levels. Particularly between change Level L9 (larger spring) and change level L10 (smaller spring). Now to blow you mind Ford switched back to a larger spring for change level L14.

In my opinion and putting aside the 289 HiPo, the biggest change level for the 289 was between change level L9 and L11. There were considerable changes to the valve train. If you really have a 67 289, I'm guessing it would probably be change level L12 or L14 (I don't think there was a change level L13.). Of course all of this is irrelevant if putting on a new top end (heads, valves, rockers, cam, etc.). You can always do a custom engine build just make sure the parts play nice together.

As an FYI NPD lists 2 springs that can fit a 67 289. Part # 6513-3 (Change level L10 up to but excluding L14) or Part # 6513-4 (From change level L14). You just need to know the year of you engine and change level if staying with the stock setup.

Another great book to get is How to Rebuild Small-Block Ford Engines by Tom Monroe.
 

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@66coupe289 I agree but I would not mix and match different spring sizes.

There was variation in stock spring sizes through the life span of the 289 which could affect performance and longevity if mixing parts from different change levels. Particularly between change Level L9 (larger spring) and change level L10 (smaller spring). Now to blow you mind Ford switched back to a larger spring for change level L14.

In my opinion and putting aside the 289 HiPo, the biggest change level for the 289 was between change level L9 and L11. There were considerable changes to the valve train. If you really have a 67 289, I'm guessing it would probably be change level L12 or L14 (I don't think there was a change level L13.). Of course all of this is irrelevant if putting on a new top end (heads, valves, rockers, cam, etc.). You can always do a custom engine build just make sure the parts play nice together.

As an FYI NPD lists 2 springs that can fit a 67 289. Part # 6513-3 (Change level L10 up to but excluding L14) or Part # 6513-4 (From change level L14). You just need to know the year of you engine and change level if staying with the stock setup.

Another great book to get is How to Rebuild Small-Block Ford Engines by Tom Monroe.
I advocated for changing all the valve springs. At 50+ years old, plus one already failing, it's time. Cool info on all the "L" differences.
 

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Discussion Starter #10
I planned on replacing all the valve springs with stock replacements, this is the tag that was on the intake. The bottom end bearings were stamped 1966 and I’m sure the engine has never been apart before. It has 38k miles and has been in a barn since 1980
 

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"Change one, change em all" is a good plan.
I got a set from a local 'real' parts house and they actually were in blue and white Ford boxes.
 

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At over 50 years old it is really stretching it to think that everything on your engine is original.

When I buy a 60s Ford, I go into it with the attitude that any and everything has been repaired, replaced or changed. Most people spent as little as possible to keep a car on the road, correct or not.

I think we have all seen some marvels of engineering on old cars that make us scratch our heads and ask "Why".
 

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Discussion Starter #14
The number on the tag are
289 c 67 14
7 a 236-a
Hopefully this helps determine what valve springs I need to order
Thanks guys !!!
 

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7 A means engine built January 1967. See my post above for the rest of the info. Basically change level 14.
 

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I'll defer that question to the experts. I just know where the charts are to decipher the tags!
 

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Thanks !!! Just to be clear I need to get the springs that say “after L 14 change” correct ?
Go here:


They have the two valve springs you mention and under the description they give the outside diameter. Measure the diameter vs what you have. It should confirm the which ones you need.
 
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