Wicked WE4
Member
- Joined
- Oct 12, 2009
Does the block need any special machining before installing a RJC main cap girdle?
RJC girdle question?
- Thread starter Wicked WE4
- Start date
turbodave231
Moderator
- Joined
- May 24, 2001
I have done several engines where I machine the pan rail down to match the cap height. That way the girdle rests directly on the pan rail and the caps without shims. You might want to check your girdle on a surface plate for flatness. I have had to surface grind girdles to make them flat and true. I believe Weber Racing machines their blocks this way.
You're right Dave. Weber even posted a vid of the machining process when they put a girdle on. Pretty cool to watch a CNC machine doing it as well.
It was posted either in the general section, engines, or lounge, but I don't have the link, sorry.
ek02
Well-Known Member
- Joined
- Jan 31, 2008
I have done several engines where I machine the pan rail down to match the cap height. That way the girdle rests directly on the pan rail and the caps without shims. You might want to check your girdle on a surface plate for flatness. I have had to surface grind girdles to make them flat and true. I believe Weber Racing machines their blocks this way.[/quote
Mine was done this way in a vertical mill. The caps were machined to the height specified by RJC, then the pan rail and front cover were machined .015 more than the caps. The caps were machined attached to the block with special allen head button bolts torqued to spec, then line honed with the girdle installed. Also, the oil pickup mounting surface was machined. Photo attached of a cap. Went together perfectly and no oil leaks. A careful machinest can install it the way RJC recommends and it will work fine, but the shims are a pain to get right. The down side to my install is that any new front cover will need to be machined. You will also have to clearance the pickup tube extension by grinding the girdle and extension. The girdle may need to be clearanced where the dipstick tube enters the pan area also. Lots of work, but I am happy with mine.
I know where that engine resides.
Mike T
Well-Known Member
- Joined
- May 3, 2013
Looks like a nice block. The sg1 would indicate that it was a service block. Was it new old stock?
Yes, it was a NOS block that Weber acquired from GM. It was built with stock main caps, a RJC girdle, and NOS front cover. It is the engine in my signature, ran a 10.45 @ 128 at the Nats last year. I'm looking for more since adding new upgrades (6766 turbo and RJC intercooler).
The bit being used in the video is a 1 1/4 high speed steel bit. As with most boring operations, the amount of material being taken off is quite minimal and does not require coolant. Generally speaking, we take .010-.015" off of the pan rail to make it square. This gives the girdle a true surface to mate to, without shims/voids between the girdle and block's pan rail, for maximum strength.
ek02
Well-Known Member
- Joined
- Jan 31, 2008
I guess with this method you need to the use the .060 shims between the girdle and the caps? I like the way Weber does it compared to the amount of material that was removed from my block and front cover, since the oil pickup surface is affected by removing so much from the block.
Then they use the wrong gasket and the oil pan leaks!
