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Thread: Franklin vs supertech valve springs *pics*

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Posts: 1-10 of 17
2014-08-10 18:55:31
#1
Franklin vs supertech valve springs *pics*
So I bought some franklin valve springs in what, 2007. I recall them being rated to 11k rpm or something insane. My engine builder has mentioned they're a bit stiff for his liking and I'm switching to supertech.

Thought it interesting that the supertech springs are so much taller. Can anyone comment on the design differences. I'm getting both springs rates measured at the same place tomorrow.



2014-08-10 20:47:53
#2
Higher spring rate typically means shorter spring. (not always)

Just like with lowering springs, the stiffer they get, they usually get shorter as well. (not always)

When you compress an object with X amount of energy, it has to be released with some sort of relationship. Differences are in material, and how the spring itself is made along with normal stacked tolerances. If you take the same length spring, but one has 100 lbs/in of force and the other spring has 400 lbs/in of force the spring with 400 lbs/in will exert a much larger force than the same length spring at the weaker rate of 100 lbs/in. That force being exerted needs to be controlled, somehow or it will harm the valvetrain in some way, shape or form. (just like lowering springs that are long and stiff will blow out a damper faster or simply age the damper at a quicker rate of pace than a properly matched set)

Yes?
2014-08-10 22:47:16
#3
y friend still has his franklins in his car and they are perfectly fine. I think you just wasted money on springs. The Franklins will take the 9k+ rpm hit all day.
2014-08-11 06:02:33
#4
Thanks for the explanation Kyle.

BlueRB240 yeah they are good springs. I don't doubt their reliability or capability at all. But I'm on a small block N/A. Every little bit helps.


Now, can you mix and match springs? aka Run the inners from say the franklins with a stock Outer 20ve spring, or a stock 20ve inner with the franklin Outer?
2014-08-11 08:06:45
#5
The springs will be designed to work together. No sense in swapping them.
2014-08-11 22:08:14
#6
Originally Posted by Kyle
Higher spring rate typically means shorter spring. (not always)


Higher spring rate valve springs can be any length.


Originally Posted by Kyle
Just like with lowering springs, the stiffer they get, they usually get shorter as well. (not always)



Bad analogy. Valve springs are different than suspension springs. They have different design purpose.

A suspension spring that is stiffer( higher rate) than stock needs to be shorter if you want to have the same ride height. The ride height is the main consideration for the spring length.

The valve spring dimension is the result from careful consideration of the camshaft lift, aggressiveness, rpm,and boost pressure. Some higher rate valve spring can be taller than the factory spring because of the danger of coil bind (bottoming) due to the higher lift camshaft.

Spring rate is affected by, material of the wire, wire diameter, spring diameter, and coil #.

If you look at the pics, the Franklin’s springs have bigger wire diameter.


Originally Posted by Kyle
When you compress an object with X amount of energy, it has to be released with some sort of relationship. Differences are in material, and how the spring itself is made along with normal stacked tolerances. If you take the same length spring, but one has 100 lbs/in of force and the other spring has 400 lbs/in of force the spring with 400 lbs/in will exert a much larger force than the same length spring at the weaker rate of 100 lbs/in. That force being exerted needs to be controlled, somehow or it will harm the valvetrain in some way, shape or form. (just like lowering springs that are long and stiff will blow out a damper faster or simply age the damper at a quicker rate of pace than a properly matched set)

Yes?



Again, a bad analogy. You can’t compare valve springs with lowering springs. The lowering springs have dampeners(shocks) to control them. The valve spring has no such thing. It job is help the valve follow as closely to the profile of the camshaft as possible. The higher rate valve spring does a better job of this.

Spring rate is very easy understand.

If it’s rated at 100 lbs/in, it means it will take 100 lbs of weight/force to compress it 1 inch.

If it’s rated at 400 lbs/in, it would take 400 lbs to compress it 1 inch.
2014-08-11 22:18:08
#7
Originally Posted by Doctor
Thanks for the explanation Kyle.

BlueRB240 yeah they are good springs. I don't doubt their reliability or capability at all. But I'm on a small block N/A. Every little bit helps.


Now, can you mix and match springs? aka Run the inners from say the franklins with a stock Outer 20ve spring, or a stock 20ve inner with the franklin Outer?


On my current build, I did some mix and matching. Ran the Franklin main springs with the factory inner springs.

You can do any combinations as long as you measure the I.D. (Inside Diameter) of main spring and O.D (Outside Diameter) of the inner spring.

An example of a combination that does not work is running the factory main spring with the Franklin Inner spring. The Franklin inner spring O.D is too big for the factory main.
2014-08-11 23:54:01
#8
Maybe my parenthesis button is not working, hmmm.... (strange)

Spring rate is affected by, material of the wire, wire diameter, spring diameter, and coil #. Length has nothing to do with it.


This is the highlight between both posts, easily collated, and simply put.

I am happy my little simple example helped explain a few relationships that can exist between similar (or same) parts from different manufacturers.
2014-08-12 07:45:57
#9
Originally Posted by KillerKrossover


On my current build, I did some mix and matching. Ran the Franklin main springs with the factory inner springs.


I recall hearing of people using the factory 20v outer with a stock inner as a good compromise on the ve motors yes, hence my question.

What spring rates did you end up with using that franklin outer and stock inner combination?
2014-08-12 08:44:22
#10
OP, I've been rocking the Supertech springs for almost 3 years. no complaints over here and they've gotten plenty of high revs.
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