Processing time- Once your order has been placed, it will take around 30 days for us to build and ship.
This valve spring kit is engineered to fit 4.3 iron Vortec heads w/ mild hyd roller cams. Intended for use w/ duration @ .050" figures between 195-218 degrees on the intake. (not to be confused w/ advertised duration, exhaust duration can be higher)
We engineered this kit with all the right parts so Vortec heads can be build without the need to machine the guide for increased lift.
This kit is specially engineered to allow for increased lifts, up to around .550".
Our vortec kits solve two common problems on these heads.
The clearance issue between the retainer and seal was solved by manufacturing the retainers to offer maximum clearance between it's bottom side and the top of the seal. The bottom of the retainer is machined so the bottom edge of the retainer is close to the bottom side of the locks. This is what gives the added clearance between retainer and seal without the need to machine the guides down.
Our vortec springs are a perfect fit on the stock Vortec spring base.
Both problems solved and no machining required!
These kits were engineered over twelve years ago and have been in use world wide with excellent results. A true and proven design with a long history of performance and durability.
Kit comes with enough parts to suit 4.3 V6 vortec engine:
Proper installation requires measuring the installed heights and shimming as required. (installed height specifications are included with kit)
Specifications:
Suitable for mild Hyd Roller cams w/ up to around 218 degrees duration @ .050" on the intake.
Requirements- Valve Seal replacement is highly recommended. It's important for the installer to make 100% sure the seals are fully seated down on the guide. Seals which are not fully seated will reduce maximum lift capacity. It's the installers responsibility to take measurements between retainer bottom and seal top to verify there is suitable clearance.
Vortec heads normally use: 11/32" X .552" seals but we have seen some guides measure up to .558". Other seal sizes are available under the 11/32" positive category.
NOTE-1- Spring installed height must be measured and shims added as required to meet target installed height.
NOTE-2- 4.3 Heads w/ double groove valves will need to change them to single groove valves as the second groove will reduce the available retainer to seal clearance.
OPTIONS- Buyers may add a hardened shim pack or premium viton valve seals by clicking the option boxes towards the top of the page.
Alex's Parts- The smart choice in valve train parts~