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M-5300-W FP spring rates

We measured the rates of the M-5300-W kit.

You can see from the plot that the fronts are linear 250-260#. Rears are effectively 565# for travel 1 through 2 ". Increasing to 735# for 2-3". Our tester doesn't go past 2.5" stroke but the spring does. Looking at the somewhat asymptotic curve, it looks like the rate would be 900-100 lbs for inch 3-4 of it's stroke.

We'll test the OEM GTG350 springs when we swap these in.

GT350_FP_Spring_Rates2.jpg
 
Thanks for posting. How does this compare to stock GT350 and GT350R springs? Do you have a chart with all three included?
 
1,102
1,072
In the V6L
Thanks for posting. How does this compare to stock GT350 and GT350R springs? Do you have a chart with all three included?

As Jason said, there's not enough data (too little travel) on the fronts to get a solid answer, but from the limited data there is, it looks like the front spring rate (258 #/inch) is about the same as a GT350R (263 #/inch) front spring. That conclusion might change with a more complete data set though.

The rear spring (735 #/inch) is softer than the R spring (836 #/inch), which in turn is softer than the non-R spring (930 #/inch).

The rates I have for the R and non-R springs are from Vorschlag's data.

I could update the graphs I made of the Vorschlag data, but I need to know the free length of the FP kit springs.
 

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