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Product Description


 This item has been discontinued


It is being replaced w/ VSK7m48-M which is our newest SBF Max Output drop in kit.

VSK7m48-M offers more seat and open pressure and is compatable with higher lifts and longer duration cams. Therefor, our older .550" lift max output kit, VSK7H48-M is being replaced with a superior version, #VSK7m48-M which is a .600" lift kit.

For further details, please use the contact us link.


Fits Factory Heads, no machining required.

MAX OUTPUT Drop In Valve Spring Kit, SB FORD GT40P, 7 Degree Hardware

Application: Hydraulic Roller, up to .550" Lift.

Fitment: GT40P 302 heads (we also offer kits for GT40 302 heads, check our other ads)


This is the Max Output version of our drop in series spring kits for GT40P engines.

Offered for applications which need more open spring pressures then our .480", .560" & .580" kits provide.

Max Output is for use with cams between 228-238 degrees duration @ .050" and up to .550" lift.


When selecting high performance valve springs and retainers for GT40P heads, special attention is required.


Unlike some of the earlier SB Fords where the tip lengths were the same for both intake and exhaust, GT40P heads use two different lengths.

They normally have .393" tip length intakes and .481" tip length exhausts.

Since the goal is to use the same high performance springs on all sixteen valves, special retainers and locks are required to make it possible.

Our drop in valve spring kit is specially engineered to fit GT40P heads.

The performance springs in this kit fit GT40P heads without additional modifications.

If you need help determining if these will work with your cam, just send us an e-mail with the cam specs or better yet, the cam brand & part number and a link to the specification page. We'd be happy to verify compatibility.

Works great with many of today's popular performance cams.




      Spring Specifications:

  • 1.480" Outside Diameter
  • 115 Lbs @ 1.810" Valve Closed Installed Height
  • Max Lift- .550"
  • 300 Lbs @ .500" Lift
  • 320 Lbs @ .550" Lift
  • Average Coil Bind @ 1.190"
  • Spring seat machining not required




     Kit includes:

  • Eight Intake Retainers, labeled for easy identification
  • Eight Exhaust Retainer, labeled for easy identification
  • 7 Degree Hardened Valve Locks
  • 16 Drop in springs
  • Spec Sheet
  • Installed height Specifications




  • GT40P heads normally have .393/.481" tip length valves
  • This kit come w/ parts to fit .393" & .481" tip length valves using Hyd Roller.

 Our Max Output valve springs are the strongest Drop in springs we offer.

Applications with smaller cams should consider our Std drop in valve spring kits. Also available under the valve spring category.

For specifications on Std kits, check our other spring kit advertisements.

Recommendations- Measure valve spring height during installation. For more information on setting up valve spring installed height, read the information we have available under the "Valve Spring Shims" category.





Alex's Parts- The smart choice in valve train parts~

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