[DeTomaso] Vibration in Longchamp, part 2

[Mikael]

So wheels are sent to get balanced (won't leave my entire car at any shop).
And the newly bought inclinometer arrived. Seemed like an accurate one,
$150, and very consistent. At the diff I measured at the flange, 0.00
degrees. At the trans there's always a bit of looseness. Measured with
propshaft just hanging (on yoke), 0.00 degrees (is it "on"? J) and then with
the yoke pushed up by hand, 0.40 degrees. So trans must be 0.20 degrees up.
Does anybody here do this for a living, can 0.20 degrees produce a
vibration?

 

So let's do some math here, and let me know if I got it wrong. There's about
115 cm from rear of trans to pivot points (engine mounts). So a full circle
of the rear of the trans would be "pi" x 115 x 2 = 722 cm. With 360 degrees
round, that would be 2 cm per degree. And I would have to lower the rear of
the trans 0.20 x 2 cm= 4 mm. That I've done. Can that really make a
difference? Looking at the old trans and mount versus new, it looks like the
new trans is between 4 and 8 mm higher, so maybe that's it?

 

Also took the chance to turn the propshaft on the rear diff 180 degrees.

 

Will not be able to test for a few days, not too optimistic.

 

Mvh/Regards

Mikael

Hass Consult ApS

+45 31770747

mikael_hass at mail.tele.dk

 

-------------- next part --------------
   So wheels are sent to get balanced (won't leave my entire car at any
   shop). And the newly bought inclinometer arrived. Seemed like an
   accurate one, $150, and very consistent. At the diff I measured at the
   flange, 0.00 degrees. At the trans there's always a bit of looseness.
   Measured with propshaft just hanging (on yoke), 0.00 degrees (is it
   "on"? J) and then with the yoke pushed up by hand, 0.40 degrees. So
   trans must be 0.20 degrees up. Does anybody here do this for a living,
   can 0.20 degrees produce a vibration?


   So let's do some math here, and let me know if I got it wrong. There's
   about 115 cm from rear of trans to pivot points (engine mounts). So a
   full circle of the rear of the trans would be "pi" x 115 x 2 = 722 cm.
   With 360 degrees round, that would be 2 cm per degree. And I would have
   to lower the rear of the trans 0.20 x 2 cm= 4 mm. That I've done. Can
   that really make a difference? Looking at the old trans and mount
   versus new, it looks like the new trans is between 4 and 8 mm higher,
   so maybe that's it?


   Also took the chance to turn the propshaft on the rear diff 180
   degrees.


   Will not be able to test for a few days, not too optimistic.


   Mvh/Regards

   Mikael

   Hass Consult ApS

   +45 31770747

   mikael_hass at mail.tele.dk