308 QV head torque

As I prepare to do the head gaskets on my car I've been reading through the manual and service bulletins and in regards to torquing the heads I'm having a bit of trouble following what they are saying. The procedure is to torque each nut to 33 ft/lbs then using a goniometer turn each nut an additional 120 degrees. The problem, and the part I don't get, is since you're using the AV 1393 adapter and your wrench is fixed to it how can the goniometer measure the angle since the nut and it's rotational center is offset from the wrench by 2 inches?

I suppose I can just mark the nut and rotate the mark 120 degrees or maybe people just go for a specific torque value?

I've done a search here but haven't come up with much.

 

Well that’s the part I don’t get - how you would use an angle gauge when the head of your wrench is offset 2 inches from the axis of the nut you are torquing. The whole assembly of wrench and angle gauge is going to move through an arc. I use a similar adapter for cylinder base nuts on aircraft engines but it has another dogleg at the top end so you have the clearance but the wrench is still in alignment with the nut.

I’ll figure it out one way or another.

 

I have a torque angle gauge, it’s a very simple tool but it needs to be directly in line with the axis of the nut or bolt you are torquing, you then fix the adjustable arm or magnet so that the gauge face remains stationary and the needle rotates as you turn your wrench the specified number of degrees. This isn’t going to work when the head of the wrench is offset from the axis of the nut. The whole thing is going to move through an arc with a 2 inch radius from the nut. I could make another adapter to hook into the Ferrari tool to bring the wrench back to the nut axis (it would look kind of like a c-clamp shape) but maybe it’s just easier to eyeball it or maybe people have just come up with a torque value to use rather than the degrees.

 

Determining the angle is not really a problem, as yelcab pointed out it’s two flats on the nut. I was just trying to figure out what they are saying and showing in the manual with the angle gauge (goniometer) I notice there is one on Amazon with a flexible cable mount like the one in the illustration shown in the QV manual, maybe that would work. It’s only 30 bucks.

 

Well there are 20 nuts and if a $30 tool makes it that much easier it's probably worth it. I have an engine I'm building for my Land Rover that has TTY head bolts so I'd probably use it again. What the heck it's only a mouse click away lol.

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Me neither, that was the whole point of my original post. That tool looks exactly like the one pictured on page B51 of the 308QV Workshop Manual. Also there is no socket, that tool has to snap into the extension that comes off of the adapter tool so the whole thing is offset 2 inches from the nut you are turning and cannot remain stationary in any case.

 

From the workshop manual:

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The angle tool arrived today so I tested it by attaching it to the head nut adapter and just turning it around a wood dowel in my vise and I'll be darned the thing actually works. Basically the flexible arm holds the dial in the same position while allowing it to swing through the arc and the pointer shows the angle. I did a test of 90 and then 180 degrees and it was dead on.

Who'da thunk?

 

Another interesting find - I also have a copy of the Mondial workshop manual in which head nut torque is listed as 10 daNm/Kgm. That would be equal to 74 ft/lbs.

So maybe that's the way to go, it's the same engine.

 

Update - disregard this entire thread as I just realized I had a complete brain-fart. The whole section on using the goniometer is for the F 105 C which is a 328. The workshop manual is a 308QV and 328 combined so you have to very careful and pay mind to what section you are in. The proper torque for a 308QV is 74 ft/lbs.

The manual is a bit tricky, maybe I should print out a hard copy with all of the 328 stuff redacted LoL.

 

Yes, finished it last summer and have put close to 5,000 miles on it since. All is good.