Who can draw CAD? Looking for solution to offsetting bellhousing on V6

[pman92]

Agreed. Boring the bellhousing to fit offset sleeves to allow fitment of the standard dowels introduces 2 locations of error (bellhousing to sleeve, and sleeve to dowel).
Also with an ID of 18.5 and OD of 20mm that doesn't leave much wall thickness (0.75mm) on the sleeve. As mentioned you wouldn't be using an endmill you would be boring or reaming a hole.

I had a search online and think I've found the dowels you're talking about.
They need to be hollow for bellhousing bolt to pass through correct? And they have a split down the side so they compress closed when pushed in (they must be a slight interference fit)?

I've slapped together the attached. Not sure if this is what you wanted or not.
The slot isn't cut right through (to make it easier to manufacture) - you can easily finish it off with a hacksaw yourself.
The slot also aligns to the axis of the offset - so use the location of the slot to determine which orientation

[vlad01]

I think in the case of dowels, I think adding a tread inside the end would be a good idea for extraction?

This might be a way to remove the factory ones too, by tapping a thread, install a long bolt through a block of steel and use that block to slide hammer the bastards out.

I'll contact the mob in China and see what they'll quote. If is is reasonable, I'll grab a micrometer and measure up the existing dowel OD and go from there.

[vlad01]

A lot of people recommend this mob. I had another mob I found as the first result on google on my phone, but it refuses to come up on google on my PC, so I decided to see what people were recommending, it's this mob.

https://www.rapiddirect.com/

But to get a quote, I need a file first. Few people on reddit say a lot of the Chinese firms are about 3-5x less cost that similar CNC services in the US, and the best regarded online Chinese ones are quite good on quality and turn around.

So I will get a micrometer, possibly tomorrow and get some dimensions up.

[vlad01]

Agreed. Boring the bellhousing to fit offset sleeves to allow fitment of the standard dowels introduces 2 locations of error (bellhousing to sleeve, and sleeve to dowel).
Also with an ID of 18.5 and OD of 20mm that doesn't leave much wall thickness (0.75mm) on the sleeve. As mentioned you wouldn't be using an endmill you would be boring or reaming a hole.

I had a search online and think I've found the dowels you're talking about.
They need to be hollow for bellhousing bolt to pass through correct? And they have a split down the side so they compress closed when pushed in (they must be a slight interference fit)?

I've slapped together the attached. Not sure if this is what you wanted or not.
The slot isn't cut right through (to make it easier to manufacture) - you can easily finish it off with a hacksaw yourself.
The slot also aligns to the axis of the offset - so use the location of the slot to determine which orientation

Yeah that's pretty close to what I had envisioned, except the total indicated run out is 0.34mm (because the dial indicator in measuring from a radius stand point), so the physical offset is 0.17, that PDF shows 0.085? Just think that the entire bellhousing shifts over by 0.17mm, to correct the 0.34mm total indicated runout.

The section of offset is only about 8-9mm from the end with the majority of the length in the block. But I think that will still work fine as they don't need to be that deep into the block and the bell housing itself has only about 2/3rd of the bore engaged with the dowel anyway

The factory dowel has no split and and interference fit is an understatement. It might be a real challenge to remove the old ones given how ridiculously tight fit they are. I have not attempted yet, but I know someone else who did and failed to even move them, but they didn't quite get to the easyouts or tapping them to run a slide hammer. They are made from a hardened steel, something close to tool steel by the feels of it. The slot will for sure make it easier to deal with. But with with the cost of the Chinese CNC mobs, it probably would be good to have them do it at the end stage of the manufacturing, it will be a lot neater than me trying to hack through it.