3 point seat belt install (SEATBELT sOLUTIONS)

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Joined
Jan 25, 2017
Messages
733
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Location
Tavares, fl
My Car
71 Mustang Mach 1
302-2v
C4

Today we dove into the 3 point seat belt install.  There was a bit of a learning curve for us to get the rear interior out, but we finally figured it all out. I didnt get a chance to take too many pictures, but I will take the time when we do the passenger side to take more to add to this thread.

The kit I got is the 3 point kit for a 65-73 fastback from CJ Pony Parts.

http://www.cjponyparts.com/seat-belt-3-point-retractable-with-push-button-front-pair-coupe-1968-1973-fastback-1965-1973/p/SBR7-V/

seat-belt-kit-1.jpg


Here are my observations on installing the kit.

The first step is to locate the Original mounting point for the factory 3 point seat belt up on the roof line.  You can locate it by pressing around on the headliner about 3 -4 inches in front of the factory coat hanger.  Once you feel it, you can trim out a hole in the headliner to expose the socket.

20170820_1711472302.jpg


If yours is rusty as hell like mine, you will need to chase the threads with a tap.  The threads are 3/8-16 coarse Thread.  Use some oil on the tap so it cuts clean.  Be extra careful starting it and watch your angle as the bolt is at a very odd angle in the roof.  Once it is tapped you can look in the kit for the 3/8-24 bolt to hold it on there.  Oh, but wait, THERE ISNT ONE.  So now you will have to stop, go to the ACE Hardware store and get a 1" long 3/8-16 coarse thread bolt (For each side).  Then you can come back home and continue working on it.  Once your back at it, use one washer inside the belt hanger and then thread the bolt in.  Start it by hand, and use hand tools to thread it in.  It will only go in about 3/8 of an inch.  It would also be wise to use some red Loctite on the threads of the bolt to keep it secure.

Once you have the top in place, then you can locate the best spot for the belt tensioner to sit.   You want to mount it on the flat part of the floor.  You dont want to get too close to the angled portion or you will be drilling too close to the fuel line that runs in the rocker on the drivers side. The door jamb plate and rear interior quarters need to come out to get to where you can pull up the carpet and mark the floor to drill the hole thru the floor pan to mount the seat belt tensioner.  Once you have the location, you can mark the floor pan with a sharpie and drill the hole.  You will need a 1/2" drill bit for the hole.  It doesnt take much effort at all to drill thru that thin metal.  Then you need to figure out where to cut the hole in the carpet and underlayment so you can bolt up the angle connector that the seat belt tensioner bolts to.  Once the hole is drilled, drill thru the underlayment to make a hole for the bolt to go thru.  As for the carpet, the way I did it was, to thread the bolt up thru the bottom of the floor and start the nut on the bolt, then lay the carpet back on top of it.  Then feel around the carpet for it and trim the hole out with a very sharp exacto knife.  Try to make it as small as you can so just the bolt comes thru.  Once that is done you can lay down the angle iron piece and bolt that to the floor.  Put the bolt thru it, push it thru the carpet and thru the floor pan.  Have someone go under the car with 2 of the giant washers and one of the lock nuts and a socket wrench with a 9/16ths socket and a light.  Then have them hold their socket on the nut while you wrench it in from the top.  Once it is all the way down and TIGHT, you can attach the seat belt tensioner to the bracket with the shorter bolts.  I used a washer on the back of the bracket, then the lock nut. If there is alot of bolt hanging under the car, you can trim off the excess with a grinder with a cutoff wheel.

20170820_1930282348.jpg


20170820_193031.jpg


Now that part is done, the easy part is finishing the job.

The long bracket end of the belt system bolts to the stock location where the original tensioner mounted.  Just use the same bolt and washers.

Next the seat belt receiver mounts up to the transmission tunnel using the original hardware.

Then you can put the seat back in place, and then the door jamb metal strip and then repeat on the other side.

The finished seatbelt fit pretty nicely.  It does run a bit high but its not as bad as I anticipated.  To lower the point that the belt crosses your shoulder you can do one of 2 things.  You can use a clip that clips the shoulder strap to the lap belt strap.  Thats sort of a pain in the rear because you will have to position that clip seat time you use the belt.



The other alternative is to mount some seat belt guides to the upper side of the seat.  The guides from a 99-2003 Camaro/trans am/firebird should work perfectly.



I got this picture from the reviews on the Scott Drake Version of this kit (The difference is, its more expensive, which seems to be that way with all their products)



I think this is what I would like to try, but my son doesnt want to drill and mount anything to the seat, so we will try it like it is for a while, and if its a problem, we will discuss this again and make a decision.

Overall I am very satisfied with the install and performance of the kit.  Its no where near as bad of an angle on the shoulder belt as I thought it would be.  There are also easy fixes for the problem if it becomes annoying later on.  The instructions from Seatbelt Solutions really arent as bad as I thought they were before doing the install.  The most helpful instructions though to me was the video on the CJP website for this seat belt kit.  They have a complete install video on it, though its in a older style car that they mount the upper shoulder mount to the inner rear quarter trim. The Roof line mounting point I had to figure out on my own, since there was little to no information online about its location.  There was no information about the thread size of the bolt that mounts there either.  I was thinking a bolt in the kit would be the right size but no.  So I had to compare the kit bolt to the hole to get an idea on what size bolt it was, then look at the threads to see if they were fine thread or course thread, then just get a couple of bolts and see what worked.

After I bought this kit, I discovered from another member that there is a version of this same kit for a Van, that has the drop link for the roof attachment that should lower the shoulder strap to a much more comfortable position.  I dont have any information on it other than that.  Maybe someone else will add that to this thread for future reference.

Note: I originally tapped the top bolt with 3/8-24 fine thread, but Don from OMS set me straight on the thread size, it is 3/8 - 16 Coarse thread. So I ran the 3/8-16 tap back thru and used the correct bolt and its holding strong. I did the other side with the correct bolt to start with.

 
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Hopefully we can finish up the passenger side today. I will post more pictures this evening.

 
You might have an issue with your upper bolts since you ran a 3/8 - 24 fine thread tap through them

While Ford used fine thread on all the seat belt floor bolts for our cars, the upper shoulder belt bolt weld nuts are course thread.

The factory bolt threads in the roof are 3/8 course thread

 
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Im pretty certain it was fine thread. I even photographed it and compared it to a fine thread bolt and a coarse thread bolt.

I will have another look at it on the other side. I have both coarse and fine thread taps and bolts, so I will look into it and make certain its not coarse thread.

Thanks for the info Don!



 




Im pretty certain it was fine thread.  I even photographed it and compared it to a fine thread bolt and a coarse thread bolt.

I will have another look at it on the other side.  I have both coarse and fine thread taps and bolts, so I will look into it and make certain its not coarse thread.

Thanks for the info Don!

Here is the factory bolt - the smaller one with the shoulder is for the shoulder harness

 
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Dang, I wish I had 2 of those bolts.

So that's 3/8 coarse thread?

 
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Finally got a chance to get out and work on the mustang today. We got the seat belts on the passenger side all taken care of in less than an hour. Now that we know what were doing it took way less time.

So we got the headliner nut exposed. I also got the correct 3/8 coarse thread bolts for this spot.



Then got the top link installed



Then marked and drilled out the hole in the floor for the seat belt retractor. Floor pan is pretty rotted on this side. I hope I can get that floor pan replaced pretty soon. I think I am going to have them weld on a 4x4" piece of steel plate where these seat belts mount to the floor then weld a lock nut to the plate when they are done replacing the floor pans. That way I will be sure it has plenty of metal there and wont pull thru the floor pan in an accident.



Then cut the hole in the carpet and installed the retractor and the strap end of the belt.





Now that is all done, we can go work on putting the interior back in, then take it for a test drive.

 
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Test Drive went pretty good. We both had difficulty with the retractor locking up when pulling the seat belts out to buckle them. I think it was that we were on an angle in the driveway. We went to the level street and it was better, but still had a tendency to lock up when pulling out. At least I know they will lock if we hit something. Other than that, it worked out great. They fit good, are not overly uncomfortable and the strap doesnt cut into my neck like I thought it would. So that project is done! On to the next one.

 
I have purchased the same kit, I have found the hole in the roof and it seems to be the same size hole /thread (course) as the bolts that hold the seat frame on.

I m not sure in the above guide why the reactor was placed and mounted to the floor pan in a different position to the end of the Belt strap?

The the long metal shaped piece on the end of the belt strap is designed to fit behind the reactor /tensioner and share the same frame hole?

I just watched the Video on the CJ Pony youtube channel, they are fitting the kit to an earlier 60s mustang. I can see why they needed to drill the floor BUT, If your fitting this kit to a 71-73 Just use the same side mount hole and don't drill the floor.

I'm using my original factory seat belt holes so most of the parts and angle brackets supplied in the kit are not needed. ;)

 
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I installed this very same kit in mine, and used the factory correct mounting bolts, instead of the ones that came with the kit - no worries, issues, or otherwise.  There is no reason to drill any new holes or otherwise.  The upper mounts go in the shoulder belt mounting holes close to what would be the 'B-pillars' (if our cars had them), the stationary belts go to the factory locations on the transmission tunnel, and the retractors/anchor points go to the factory mounting points in the rockers (right behind the door openings).

Yes, both mounting brackets can share the same hole(s).  They're solid anchor points directly in the uni-body 'frame' section of the rockers (not the floor pan sheet metal).  Kind of a clunky design, but I'm guessing it's more of a universal kind of design, despite being spec'd for our cars.

I will say that the plastic on the trim piece of the retractor where the belt feeds out is kind of brittle, as mine's cracked already after just 5 years of installation, being garage-kept, and very light use.  But otherwise, I love 'em.

 
I do not have retractable three-point belts in my FB, I have considered adding them but that's down the road.

At risk of coming off troll-ish, I don't think this (photo blatantly stolen)



Is a good idea. This mounting scheme will pass all of the load from an impact through the fasteners holding the clip or belt guide to the seat, and if those fasteners somehow don't fail, the seat back retaining mechanism.

If the force is enough to fail the belt guide fasteners or the seat back mechanism, the upper body of the occupant is not restrained, and that is bad :(

Carry on...

 
I can't see your picture from here at work, but I believe the fasteners that come in the kit are Grade 8.  As well, substituting the factory-style fasteners should also be fine because I believe those to be Grade 8 as well.

After becoming intimately familiar with the sheet metal in and around the floor pans (I replaced mine, along with about 60% of the rest of the factory sheet metal due to rust issues), I can honestly say that the seat belt mounting points on our cars are just as solid as any of the other [more modern] cars I've worked on in my lifetime so far.

Having said that, I wouldn't trust the factory seats to offer much in the way of extra support during a major impact.  In fact, I wouldn't really say that our cars are anywhere close to being as safe as the modern cars.

You don't want to be in an accident in one of these cars, anymore than you'd want them to suffer any damage at all.  However, the 3-point kit, in my opinion, is inherently safer and should offer the same if not better protection during an impact than what the factory dual-belts could provide.  That, and there aren't any clips to fail and drop that shoulder belt on your head while you're rolling over bumps in the road (unlike the ones in my Mom's '70 Galaxie 500).

 
Eric-

In case it didn’t show up, the pic I stole and was referring to shows the belt coming down from the roof through a retaining loop attached to the side of the seat and then across the shoulder of the occupant.

I am with you that the crashworthiness of a 1971 vehicle isn’t comparable to hat of a modern car, my comment was my opinion that as shown in the picture, the installation of the retractable belt kit would be worse than the original, non-retractable, Ford-designed separate shoulder and lap belt system.

I wouldn’t want somebody to go through the trouble of adding the retractable belts only to be worse off.

Again, that’s just my opinion.

Carry on!

-Matt

 
Eric-

In case it didn’t show up, the pic I stole and was referring to shows the belt coming down from the roof through a retaining loop attached to the side of the seat and then across the shoulder of the occupant.

I am with you that the crashworthiness of a 1971 vehicle isn’t comparable to hat of a modern car, my comment was my opinion that as shown in the picture, the installation of the retractable belt kit would be worse than the original, non-retractable, Ford-designed separate shoulder and lap belt system.

I wouldn’t want somebody to go through the trouble of adding the retractable belts only to be worse off.

Again, that’s just my opinion.

Carry on!

-Matt

I saw the pic when I got home last night, and noticed what you were talking about.  That's a custom addition to that particular seat - it looked like it had Deluxe seat upholstery that would've been correct for our cars, however that seat belt loop is completely out of place.  It could also be an aftermarket seat (like Distinctive Industries, TMI Pro Seats, or something else altogether).

I'm not a fan of those, either.  I'm also pretty sure they're not designed for any kind of support during impact.  I broke one off my wife's 01 Grand Prix driver seat a few years ago, and had Hell trying to find a replacement.  It was plastic.  She insisted she needs it because it keeps the shoulder portion of the seat belt in a better position for her (since she's only 5'2").  My Mom has the car now (she's taller at 5'7") and doesn't care that I still haven't replaced it.  Something I did notice is the loops on her '15 Camaro seats are nothing more than canvas loops sewn to the seats with snaps to close 'em up around the belts.  I know those will definitely not offer any support during a crash... but then again, there are airbags galore on those cars (we found out the hard way in Aug 2017 when we got T-boned on the freeway - long story).

 
Eric-

In case it didn’t show up, the pic I stole and was referring to shows the belt coming down from the roof through a retaining loop attached to the side of the seat and then across the shoulder of the occupant.

I am with you that the crashworthiness of a 1971 vehicle isn’t comparable to hat of a modern car, my comment was my opinion that as shown in the picture, the installation of the retractable belt kit would be worse than the original, non-retractable, Ford-designed separate shoulder and lap belt system.

I wouldn’t want somebody to go through the trouble of adding the retractable belts only to be worse off.

Again, that’s just my opinion.

Carry on!

-Matt

I saw the pic when I got home last night, and noticed what you were talking about.  That's a custom addition to that particular seat - it looked like it had Deluxe seat upholstery that would've been correct for our cars, however that seat belt loop is completely out of place.  It could also be an aftermarket seat (like Distinctive Industries, TMI Pro Seats, or something else altogether).

I'm not a fan of those, either.  I'm also pretty sure they're not designed for any kind of support during impact.  I broke one off my wife's 01 Grand Prix driver seat a few years ago, and had Hell trying to find a replacement.  It was plastic.  She insisted she needs it because it keeps the shoulder portion of the seat belt in a better position for her (since she's only 5'2").  My Mom has the car now (she's taller at 5'7") and doesn't care that I still haven't replaced it.  Something I did notice is the loops on her '15 Camaro seats are nothing more than canvas loops sewn to the seats with snaps to close 'em up around the belts.  I know those will definitely not offer any support during a crash... but then again, there are airbags galore on those cars (we found out the hard way in Aug 2017 when we got T-boned on the freeway - long story).



Wait a minute ... T-boned on the freeway :chin:

Freeways around me are 3-4-5 lanes of traffic all going the same way

I knew you would find a way to get the Chevy out of the garage :whistling:  rofl rofl rofl rofl

 
Eric-

In case it didn’t show up, the pic I stole and was referring to shows the belt coming down from the roof through a retaining loop attached to the side of the seat and then across the shoulder of the occupant.

I am with you that the crashworthiness of a 1971 vehicle isn’t comparable to hat of a modern car, my comment was my opinion that as shown in the picture, the installation of the retractable belt kit would be worse than the original, non-retractable, Ford-designed separate shoulder and lap belt system.

I wouldn’t want somebody to go through the trouble of adding the retractable belts only to be worse off.

Again, that’s just my opinion.

Carry on!

-Matt

I saw the pic when I got home last night, and noticed what you were talking about.  That's a custom addition to that particular seat - it looked like it had Deluxe seat upholstery that would've been correct for our cars, however that seat belt loop is completely out of place.  It could also be an aftermarket seat (like Distinctive Industries, TMI Pro Seats, or something else altogether).

I'm not a fan of those, either.  I'm also pretty sure they're not designed for any kind of support during impact.  I broke one off my wife's 01 Grand Prix driver seat a few years ago, and had Hell trying to find a replacement.  It was plastic.  She insisted she needs it because it keeps the shoulder portion of the seat belt in a better position for her (since she's only 5'2").  My Mom has the car now (she's taller at 5'7") and doesn't care that I still haven't replaced it.  Something I did notice is the loops on her '15 Camaro seats are nothing more than canvas loops sewn to the seats with snaps to close 'em up around the belts.  I know those will definitely not offer any support during a crash... but then again, there are airbags galore on those cars (we found out the hard way in Aug 2017 when we got T-boned on the freeway - long story).



Wait a minute ... T-boned on the freeway :chin:

Freeways around me are 3-4-5 lanes of traffic all going the same way

I knew you would find a way to get the Chevy out of the garage :whistling:  rofl rofl rofl rofl
Oddly enough - yes, "T-boned on the freeway."  We were heading up the on-ramp, got to speed, merged in front of an F-150, and a late-model Dodge Dart was doing 90+ behind the truck, changed lanes, lost control, was sliding sideways through the median passing the F-150 (that's how fast he had been going), caught some traction when his front wheels got back on the asphalt, and shot right into the driver side of her car.  After everybody finally got stopped, he somehow got his car started and fled the scene (of course).

Here's the damage:

crash3.JPG


Here are the airbags that deployed (also notice the crease in the rocker = totaled) - the black strap with chrome snap just under the airbag on the right side of the pic is the seat belt loop I mentioned earlier.  Surprisingly, it didn't come unsnapped during the crash): 

crash1.JPG


Rest assured, though - there's still a Camaro in the fleet.

carmen1.jpg


 
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