Why Are The Ultra High Rockers Not Suited To VYs?

The VY model ecotec engines suffer from excessive casting flashes in the push rod holes in the heads.  When you fit our extreme high ratio 1.98 rockers the push rods rub on those casting flashes leading to a noisy valve train.

For the VY models we recommend our 1.9 high ratio rockers used with our 5/16" push rods to ensure proper clearance.

Another option would be to clean up the casting flashes in the push rod holes, this can be done if your careful, however we don't recommend it with the heads fitted to the engine as you risk getting metal into the engine/oil.