Subject: Bellhousing
From: ACRE
Date: 6/23/2003, 9:07 AM


George Lendich wrote:

George Lendich wrote:

Paul,
Good news and bad news.

The good news is the bell housing will cost about $150.00.
although this is yet to be confirmed and won't be confirmed until I
do
one.

Other good news is that the auto flexplate will fit with some
machining.
The bad news is that it will need some machining for the auto
flexplate.
The other good news is that it won't need to be machined for the
manual
ring gear.

Because of the size of the auto flexplate 320mm Diameter
(please check that your is the same diameter) there is little room
between it and the bolt holes.
180 mm centre to centre for the odd one out.
182 mm centre to centre for the remainder
160 radius for the Auto flexplate
20 -22mm remaining

2mm for clearance of the flexplate to the inside bell housing wall
6mm for wall thickness
12 mm for radius of the bolt head
I.E. 20 mm

The bellhousing wall has a sloped wall surface about 4mm in 80mm or
2mm
in 40mm where the ring gear travels. This taper is need
for sand casting.

So you can see this is very tight indeed. What will need machining
is
the inside bell-housing (from 9mm to 6mm or a little
less). I made the housing 9mm thick in this area as I am using a
manual
ring gear on aluminium flywheel (similar to
the Ross) and wanted to beef-up this area as it seemed thin at 6mm.
With
the manual ring gear there is plenty of room.

The area needing machining is a small area within the arc of the
bellhousing. A straight cut on mill -in an arc would do the
job.
How is that sounding Paul,
George (down under)

The price is great. I assume that is US dollars.

Without a drawing or a lot more pictures it is hard for me to
visualize.
The vast majority of us here in the States are using the auto tx flex
plate
and ring gear.


Yep I realise that Paul, That's why I tried so hard to fit it in.
However there are a few different flexplates, is the one your using
320mm. I
only have the early 12A one here.
The price I quoted was Aust Dollars as was quoted to me from the
foundry -
still to be confirmed !!
There would be transport and machining costs on top of that.
I will do more photos.
George (down under)

I don't know. Mine is up at the hanger. Anybody got a flex plate handy?

Paul Lamar


Paul, when I switched to Tracy's PSRU I recall that the flexplate on the
Ross was 11.7" dia [297mm] and the regular 13B flexplate was an inch larger or 12.7"
= 161.25MM radius.  So looks like George's radius of 160mm for the flexplate
is a bit tight.

Ed Anderson

Yes it does. Not good George most of us have the auto tx flex plate.
Thanks Ed.

Paul Lamar
 
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