Well............ going by some Rock Climbing basic's... Id say its 50/50 on it being safe.
The angle of the chain is wrong. The force it pushing outwards onto the garage beams, that is also multiplied by the angle.
*Can't get the link to show up properly.. so you will have to copy paste*
http://en.wikipedia.org/wiki/Anchor_(climbing)
Here check out that link...
* At a V-angle of 30 degrees, each of the two anchors bear a force of about 52% of the original load.
* At 45 degrees, each anchor bears about 54% of the load.
* At 60 degrees, each anchor bears about 58% of the load.
* At 90 degrees, each anchor bears about 71% of the load.
* At 120 degrees, each anchor bears a force equivalent to 100% of the original load. An angle this large should never be used.
There is a picture on the link with the V angle explained. By the looks of it you are getting close to 100 degree angle... so your roof is holding nearly another 90+% weight of your car.
Use the chain on the right to lower the hoist a lil.
Also you can re-tie the ratches with this knot
http://www.animatedknots.com/waterknot/ ... dknots.com
Edit:... Actually Im gonna go out on a limb here and say its UNSAFE. Sure its holding the load up etc etc but you will be in the danger zone..
http://www.secureaload.co.nz/ratchet_tiedowns.html
Those tiedowns on top got a "lashing" limit of 750kgs (I think the lashing and load limit's will be different)
So how much would your car weigh?... then times it by 1.9... 500kgs maybe?... 950kg is the weight on those ratchet's and garage beams.