Visit The Dirt Forum for More Information

Author Topic:   pop-ups and vortecs
cleatus
Member
posted November 25, 2001 09:14 AM
You will have to notch the pistons for clearance of the spark plug knob (for lack of better description....lol). Remember , that Vortec heads have a faster burning chamber , so I wouldn't start with much over 34deg. of timing . It would be money well spent to run your car on a chassis dyno to find what your engine will like for ignition timing .


cleatus
Member
posted November 26, 2001 01:12 AM
You can contour the spark plug boss some . But you should machine most of your clearance into the piston . If there is someone in your area who can cut valve notches (they will have the proper piston vise) , then they should be able to properly machine your pistons for you . You should make everything clear without a head gasket on , and once you add your head gasket , you'll have the proper clearance (Min. .035") . And yes , I would use clay to find out exactly where you need to modify your pistons .


Back to the Archives