Slotting stock rockers
 

I need to open up the slot on a set of sbc rockers to fit 7/16 rocker studs. I have access to a mill at work but wondered how to set the rocker up in the vise.
TIA
Skip

Re: Slotting stock rockers
 

Skip,
I cut a set a few years ago, and had same questions and issues. I ended up making a metal bracket that held them down, as I did not want to clamp the rocker itself. Sorry, I do not have the bracket anymore or would send a picture.

However you do them, keep plenty of fluid running on the cutter, to help keep heat down.

Good luck.

Ken

Re: Slotting stock rockers
 

There are several outlets for the 7/16" small block rockers, even though I have a mill, I'm not sure I'd bother with trying to open a set of 3/8" rockers up to fit.

I would certainly not clamp them in a vise, as you will likely not be able to hold them securely enough. I think I'd take a piece of flat stock and mill slots in it to set the rockers in, and then clamp the flat stock and the rocker to the mill table. You need to put something between the clamp and the rocker to prevent the clamp from scoring the rocker, as the scoring will create stress risers.

Ken is correct, any heat generated by cutting the rockers will ruin the heat treat, it must be carried off by coolant. Are you going to have to drill the rocker balls as well?

Re: Slotting stock rockers
 

Find a shop in your area or someone who works at a shop that has a wire EDM machine. No stress and cuts like butter.

Re: Slotting stock rockers
 

Thanks guys for the advice. :)

Re: Slotting stock rockers
 

Skip, look here-http://competitionproducts.com/prodinfo.asp?number=6151

Buy 2 sets and have spares. They are pretty tough !

Re: Slotting stock rockers
 

Thanks Kenny, a friend showed that to me a little while ago. I sprang for a new set of GM 3/8" quite a while ago intending to eventually get around to opening them up.:( I had already bought the 7/16 balls too. Maybe I need to have a garage sale?

Re: Slotting stock rockers
 

No problem , Skip ! I think you would do better by getting those than having possible issues with modified ones splitting , and they are fairly cheap too. You can come up with a service life, depending on your spring pressure, and keep rolling ! Good luck !

Re: Slotting stock rockers
 

A few of years ago I upgraded my rocker studs to 7/16 and hand fit the studs to the rockers. This was done in my garage, nothing high tech but careful grind/polish to keep heat generation low and "soft jaws" that leave no stress risers. A paper clip was used to check rocker/stud clearance through the travel. Put it all together and checked valve lift to make sure I didn't gain any static lift.
All was well until I started the engine and there was no oil out of most of the pushrods. A call to Schubeck and all the lifters came out and apart to regrind the oil slot inside the lifters. Some intermittant QC problem he was aware of.
After that they are still in service several years later. It would be much better to buy the new CP 1.5 X 7/16" units but we were heading to Mission the next day.