3.6 Hydraulic to mechanical rocker conversion

[Cupcar]

Is it necessary to plug the splash oiling holes that are in mechanical rockers when they are installed in a 993 hydraulic rocker camshaft housing?

Can the 993 camshaft spray bar be changed to 930 mechanical style and the holes in 993's hydraulic rocker shaft be plugged so rockers are splash lubricated as usual?

People's experience here would help, I hate to re-bush new rockers just to close the holes.

[Flat6pac]

The hydraulic cam carriers are completely different, you will also need valve covers which are different too.
Bruce

[BURN-BROS]

Originally Posted by Cupcar

Is it necessary to plug the splash oiling holes that are in mechanical rockers when they are installed in a 993 hydraulic rocker camshaft housing?.

I would keep them pressurized. It is the best setup out there IMHO.


But you can convert everything to splash IF rebushing is completely out of the question.


Do not forget to have the new cams grooved if you retain the pressurized rockers!

[Cupcar]

Thanks for the tips.

I will rebush without the splash oil holes. And make sure cam journal is grooved! I too like the idea of the pressure oiling.

One thing, I wonder if there is any oiling percentage in drilling small spray holes in the new bushing where the original splash holes are on the rocker, one hole points at the adjuster and the other at the camshaft. This would add a touch more oil to those surfaces. Any thoughts on this?

[BURN-BROS]

One thing, I wonder if there is any oiling percentage in drilling small spray holes in the new bushing where the original splash holes are on the rocker, one hole points at the adjuster and the other at the camshaft. This would add a touch more oil to those surfaces. Any thoughts on this?

I would not mod it. It's after the cam journal which may result poor pressure locally.

Maybe a spray bar mod, but I have not heard of oiling issues associated with the 993 setup.

[Cupcar]

Originally Posted by BURN-BROS

I would not mod it. It's after the cam journal which may result poor pressure locally.

Maybe a spray bar mod, but I have not heard of oiling issues associated with the 993 setup.

Thanks, I'll keep it simple.

[Trophy]

From what I understand, if you have new arms you can press out the bushings and turn them 180 degrees and press back in, this will cover the holes.....

[Cupcar]

Originally Posted by Trophy

From what I understand, if you have new arms you can press out the bushings and turn them 180 degrees and press back in, this will cover the holes.....

Duh, I should have thought of this. I will try and get back here.

[Cupcar]

Went out to the shop, figured a 14 mm and 20 mm socket would make a nice set of press tools, set up my press and Bingo pressed in and out a bush. Note last post was at 2:06.

Note the bush is split and I put the seam at just before 12:00 and this blocked the oil ports as well as put the seam and ports opposite the most loaded part of bush.

I owe Trophy a

[Trophy]

Next time I am in soCal I will collect....

Mind you I think I owe you one as well, you have been helping me out a bunch.....

[Cupcar]

A post script to pressing out the bushings.

The first bush went perfectly but some didn't. Some of the bushings ended up too tight on their shaft, probably due to distortion when pressing them in and out.

I think they are normally pressed in and then honed to size.

End of story, they are all being sent out for fresh bushings.

I am still good for a beer to Trophy though...

[Cupcar]

Well, at least I only unbushed 3 rocker arms.

I called Patrick Motorsports where I sourced the conversion kit and was told that the kit is sourced from Germany and engineered to work as is.

So, I took a second look at the parts and found that the oiling hole in the kit's rocker shaft is substantially smaller than the stock rocker's

This smaller hole reduces flow and the 930 style rockers do not have to be modified in any way.