Geoffrey

While I have my engine partially apart I wanted to upgrade my 993 camtowers with an idea I had floating around. The 964 has cam spray bars that oil each cam lobe and spray oil at the intake rocker arms / springs. The 993 cam spray bar has the same holes that oil each cam lobe (but smaller diameter) and no oil holes on the intake side. This is because the 901 rocker arm (all pre 993 engines) rely on splash oil for lubrication. The 993 rocker arms have pressurized oil from the cam tower oil galley.

So, I drilled out the plugs in the 993 cam tower and removed the spray bars and added the intake oil hole and enlarged the cam lobe holes to 993 size.

Pictures:
Top is 964 spraybar
Middle is modified 993 spraybar
Lower is stock 993 spraybar

The last picture are the plugs I removed to remove the spraybar. The larger ones I drilled, tapped, and pulled out with a slide hammer. The smaller ones I drilled, tapped, and removed with a bolt and washer stack.

Bill Verburg

this is for use w/ mechanical adjusters?, any other mods needed?

Geoffrey

I run mechanical adjusters in my engine for sure, actually they are the 9M rockers.

There are always mods one can find to do...