The Rodding Roundtable

Motorhead Message Central => Rodder's Roundtable => Topic started by: Crosley.In.AZ on March 19, 2009, 10:07:59 PM

Title: Adding seat belts to a uni-body old car
Post by: Crosley.In.AZ on March 19, 2009, 10:07:59 PM
I need to add seat belts to the old  1961  Dodge Lancer.  It was never built with mounts for seat belts.

From what I read ... plates at least 4x4 inches 1/8 inch thick would be added under the floor of the car.

Suggestions?

:?
Title: Adding seat belts to a uni-body old car
Post by: enjenjo on March 19, 2009, 11:41:53 PM
I usually make them myself. I cut the plates, round the corners, and bend the edges down a bit so in an accident they won't just shear through the floor. I weld a 7/16" nut behind the plate to hold the seatbelt bolt, and rivet, or weld them to the floor so one person can install the seat belt from the top.
Title: Adding seat belts to a uni-body old car
Post by: C9 on March 20, 2009, 09:18:00 AM
Take a look under the floor, there may be factory installed threaded bungs in the floor and ready to go.

Found that to be true with my 62 Ford wagon and I think the 61 Ford hardtop had them as well.

That was about the time period when seat belts were mandated by the gov't to be available at the dealer level.
The factory threaded bungs sure made life easy.

Little brother had a 62 Plymouth 2 door post with belts in it and I'm not sure if he had to drill or not.

Even today, most aftermarket lap belts for passenger car street use come with a big washer.
Title: Adding seat belts to a uni-body old car
Post by: phat rat on March 20, 2009, 09:43:13 AM
I'm with Frank on the way to do it. A big washer isn't enough IMHO
Title: Adding seat belts to a uni-body old car
Post by: sirstude on March 20, 2009, 10:10:13 AM
I built a hammerform to build my seatbelt reenforcement.  It is about 4 inches long by 2.5 wide.  When you hammer the edges around it, they end up like the older factory stuff, that is pretty stiff.  I will take a picture this weekend of the form and post it.

Doug
Title: Adding seat belts to a uni-body old car
Post by: Crosley.In.AZ on March 20, 2009, 08:49:48 PM
I've been under this 1961  car many times... no factory seat belt spots in the Dodge..

My 1962 Falcon had the bolt hole spots
Title: Adding seat belts to a uni-body old car
Post by: The Paisano on March 23, 2009, 10:14:21 AM
Tony just make sure you use grade 8 bolts,nuts, and washers.
techtnicly this stuff nees to be able to withstand a lot of psi's on impact which I hope never happens.The channel steel you plan to install under the floor boards should be ok,just make sure you tie them into the strongest part of the floor boards.also,installing used belts might not be too good of an idea.they can be worn out or been sitting in the junk yard a long time.You never know if they were on when the reason the car ended in the junk yard to begin with.
Title: Adding seat belts to a uni-body old car
Post by: Crosley.In.AZ on March 23, 2009, 07:49:51 PM
hi,

what I have decided to use for metal under the floor is some 2 x 3 tube I have.  It is heavy wall .  

I will cut a piece 3.5 inches long.. then split it with my plasma cutter on the 2 inch wide side.  So I then have two flat pieces with rolled up edges and corners.
Title: Adding seat belts to a uni-body old car
Post by: enjenjo on March 23, 2009, 08:02:39 PM
That should work.
Title: Adding seat belts to a uni-body old car
Post by: 38HAULR on March 25, 2009, 12:22:53 AM
In "OZ"   The requirement is a 75x50mm    3mm thick plate, with the edges on the floor face to be bevelled ,so as to avoid "punching' the floor ,should collision occur...........Frank.
Title: Adding seat belts to a uni-body old car
Post by: Crosley.In.AZ on March 25, 2009, 11:52:41 PM
here is the design of metal I will use... 2x3 tube split.  Each end is beveled to match the sides.
Title: Adding seat belts to a uni-body old car
Post by: 38HAULR on March 26, 2009, 12:04:50 AM
3x2 in the old imperial measurement looks close to 75x50mm in my book,took some of us "older folk" a while to adapt to this metric stuff,even though we went metric in the mid 70,s :)  :)  :)  :)    Frank.
Title: Adding seat belts to a uni-body old car
Post by: Crosley.In.AZ on March 29, 2009, 02:00:21 PM
the view of welded on nutz
Title: Adding seat belts to a uni-body old car
Post by: enjenjo on March 29, 2009, 02:20:37 PM
That looks good from here.
Title: Adding seat belts to a uni-body old car
Post by: Crosley.In.AZ on March 29, 2009, 04:05:01 PM
Quote from: "enjenjo"That looks good from here.

btw... I used 1/2 inch nutz on the plates..
Title: Adding seat belts to a uni-body old car
Post by: jaybee on March 29, 2009, 04:26:48 PM
Looks about perfect.  Do those get attached to the car body in some way then, maybe plug welded through the floor in 1-2 places or glued with some dabs of silicone just so they don't fall off?
Title: Adding seat belts to a uni-body old car
Post by: enjenjo on March 29, 2009, 04:40:49 PM
Quote from: "Crosley"
Quote from: "enjenjo"That looks good from here.

btw... I used 1/2 inch nutz on the plates..

Where you going to find 1/2" seat belt bolts? All I have seen are 7/16" or 12 mm.
Title: Adding seat belts to a uni-body old car
Post by: Crosley.In.AZ on March 29, 2009, 11:25:27 PM
Quote from: "enjenjo"
Quote from: "Crosley"
Quote from: "enjenjo"That looks good from here.

btw... I used 1/2 inch nutz on the plates..

Where you going to find 1/2" seat belt bolts? All I have seen are 7/16" or 12 mm.

The GM seat belt bolts I pulled out my parts bin were 1/2 inch.  Gen 1 Camaro stuff with some 70's  Impala parts too.
Title: Adding seat belts to a uni-body old car
Post by: enjenjo on March 30, 2009, 10:20:09 AM
Quote from: "Crosley"
Quote from: "enjenjo"
Quote from: "Crosley"
Quote from: "enjenjo"That looks good from here.

btw... I used 1/2 inch nutz on the plates..

Where you going to find 1/2" seat belt bolts? All I have seen are 7/16" or 12 mm.

The GM seat belt bolts I pulled out my parts bin were 1/2 inch.  Gen 1 Camaro stuff with some 70's  Impala parts too.

As long as you have some, all is good then.
Title: Adding seat belts to a uni-body old car
Post by: Crosley.In.AZ on March 30, 2009, 09:45:28 PM
I would think regular grade "8"   at 1/2 inch size  bolts would function too.
Title: Adding seat belts to a uni-body old car
Post by: enjenjo on March 30, 2009, 10:48:07 PM
Quote from: "Crosley"I would think regular grade 8 1/2 inch bolts would function too.

It depends on the type of mount the belts have. Some of them the bolts have a shoulder that fits through the belt bracket, and bottoms out on the floor. that way the belt bracket can turn to the direction of the forces on it.
Title: Adding seat belts to a uni-body old car
Post by: Crosley.In.AZ on March 30, 2009, 11:51:55 PM
I'm not seeing a problem here.  

8)
Title: Adding seat belts to a uni-body old car
Post by: enjenjo on March 31, 2009, 12:35:36 AM
I don't either. :shock: