Thoughts on a Top Tether Point

[RNajarian]

I am looking to install a Cosco Highback 3 point harness car seat for my 4 year old son in my 1975 Targa

The carseat fits well in the back, I will be able to secure the base of the carseat via 2 racing Eyebolts 7/16-20 (with the shoulder to provide lateral strength).

The top tether attachment snaps well to the rear shelf seat strap loop, however though esthetically acceptable, I doubt sheet metal screws screwed into the rear shelf would withstand a sizable impact, thereby rendering the purpose of the top tether useless.

It would be a simple to drill into the rear shelf and place a large metal base (4 X 6) underneath to screw the seat strap loop into. However, doubt the loop itself is strong enough to withstand a rear impact.

My questions are;
1) Does anyone know how strong these seat strap loops are?
2) Can they withstand a 40 mph rear impact?
3) Any Suggestions for a replacement?

Here is a photo of the rear shelf seat strap loop.

[bkreigsr]

Those luggage strap guides are not meant for any kind of impact restraint. Don't use them. What you see is two sheet metal screws, self tapped into the rear firewall - no reinforcement. Look elsewhere for a proper anchor.
I suggest drilling a new hole in the firewall, adding a seat belt restraint washer inside the engine compartment, then bolt in a race seat belt eye-bolt.
Bill K

[Oldporsche]

You might be able to remove those screws and run a drill bit down into the engine compartment. Then you could reinforce the attachment any number of ways. Don't use that luggage strap thing for a car seat.

[RNajarian]

Below is a diagram provided from a major child car seat manufacturer on how to install the top tether for the toddler/youth car seat

I was thinking of doing something like this but in addition to the bottom washer use a large thick sheet of steel for additional strength