Build 86 Xtra Cab Build (4Wheelunderground 3 link front, 4 link rear and 3.4 swap)

[aztoyman]

Had a hell of a time the last few years. Some family stuff and some health stuff. Things are beginning to settle down but not completely. I'm really anxious to get going on this build again.

My PRP seats are still in the boxes and I haven't been able to get the tire mounted on the bead lock. Its not because I've lost interest.

 

[Broski]

Best hopes that clear sailing is in you future !!

 

[aztoyman]

Thanks Broski.

 

[ntsqd]

No pressure, just wanted to check in.

 

[aztoyman]

It's good to know you guys are still interested. Got clobbered by life events but I'm still on two feet. I'm anxious to get going again.

 

[thetoyotaman]

Some family stuff and some health stuff. Things are beginning to settle down but not completely. I'm really anxious to get going on this build again.

I can totally relate to this and have enjoyed the thread. Take care.

 

[aztoyman]

I had a free day and decided I was going to do "something" on my truck. I decided to mount my spare tire and then realized I never ordered a set of spacers when I bought the wheel. Raceline had a KOH sale going on so I ordered one set and some spare ring bolts and inserts. So much for my "free day".

I have Mickey Thompson tires with super thick beads so I ended up needing 3/8" of spacers. 1/8" is all that is offered and they are about $25 per wheel by the time they get to your door...... for 1 set. I needed 3 sets for 5 wheels. I wasn't spending that much so decided to make a set from 1/4" ABS to add on top of the 1/8".

Raceline got my stuff to me pretty quick and I had half a day open up.
I traced a spacer on a piece of 1/4" scrap steel and cut it out for a pattern. Then traced it on the piece of ABS sheet I got on Amazon and cut out the rough shape with a jigsaw. Clamped them all on the metal jig and drilled the first hole. Added a bolt and drilled the opposite side. Added that bolt before drilling the rest. With it all bolted together as one, I finished the shape on my belt sander.

To add, I actually did the same thing way back when I ordered my other wheels. I had to make another metal spacer because it gets reduced in size a little since I use it aa a grinding guide.

After all this I forgot to get a valve stem. Fortunately I remembered I ordered extras last year and managed to find them in all my junk. At least I got it mounted up.

Next chance I get, the plan is to set it in the bed to make sure I can attach my roll cage back stays where I hope to put them. (Where @ntsqd suggested) The roll cage is my priority to move forward.

 

[aztoyman]

I FINALLY got a couple days to work on this build. I did get the spare up into the bed so I can figure out back stay anchor points. Since the seats and harnesses need to attach to the cage, I played around with how I was going to mount the driver seat and where exactly.

I fit a couple tubes across the driver side floor that will end up supporting seat rails that the PRP seat tabs can attach to. I decided against installing sliders. Once I set my seat where I like it, I never move it. Plus they add height I don't want. I can fold the seats forward to get behind them.

Before I pulled my 2nd Gen 4Runner bucket, I measured my preferred adjustments. I left the passenger side in as a visible reference. I checked he height from floor and the angles of the bottom cushion and back. It was comfortable, I just couldn't move it further back like I wanted.

I sacrificed a couple pieces of angle for mock-up. I drilled a bunch of holes an inch apart so I could try the seat in various positions besides my original favorite setting since I would be moving it a lot further back.

I settled on the front seat rails sitting on top of my floor tube and the rear attaching to the bottom. Puts a really comfortable angle to the seat base and I can still adjust the back angle as needed. Just in case my wife or a shorter person has to ever drive my truck, I drilled 4 more holes an inch apart so it can be moved forward. Just a matter of 4 easy to get to nuts and bolts. I can't really add more since the rails will stick out forward of the seat too far.

I did see that my taller seat backs are too far above my main hoop horizontal bar. Unsafe to attach my harness to. I thought my horizontal bar was supposed to be at the outer bends of the uprights. I really need it to be 3 inches or more higher up. I found out it doesn't HAVE to be at the bends. It can be wherever the harness needs it to be OR I could add another bar. That would look like hell so I'm going to cut my tacks (big tacks) and raise the bar.

I was all excited to be back on this and forgot I got a letter for jury duty. I don't know when they started this, but now it requires being on call for the week. Fuuuuuuhk!!!! The last time I got picked, the case lasted over two weeks.

Sorry you had to read all this and get no pics. Tomorrow you'll be able to see what the hell I'm talking about. I'm going to have to bend my shifters too.

 

[littlevulture]

Always enjoy an update if theres no pics...but I am curious to see what you're talking about with the seat back being too high whenever you get around to uploading some pics.

 

[aztoyman]

@littlevulture , The slot for the harness is right at the top of my shoulders. The shoulder harness can compress my spine in a forward impact if it angles excessively downward from my shoulders and back to the harness bar. There is actually a spec for how much that angle can safely be. The bar is pretty close to the back of my seat and the top of the bar is 3" or more below the slot. I'll double check after the seat is solidly in position.

If my big butt was pressing at great force in a frontal impact against the straps, the load on the straps is straight out from the bar. If the bar is far enough below my shoulders it's going to put downward force on my shoulders potentially compressing my spine. Hopefully I explained that correctly. There's plenty of how to properly install a harness instructions out there if you want more specifics.

I don't know how the race teams deal with that during driver changes in race trucks. Maybe both drivers fall within tolerances? Maybe they have multiple mounting points they can clip the harness to? This is all new to me.

 

[aztoyman]

@littlevulture Here's a couple pics. Hopefully this answers your question.

 

[gnob]

is it a big deal to move the bar? or just anchor the harness to the upper bar?

 

[ntsqd]

What I recall from dim memory is the shoulder straps need to be between 90° and 85° down relative to the spine as the seat is placed. It might be 10° down instead of 5°, but that horizontal tube is definitely too low. Likely a lot of work to move it higher?

I have seen a second tube added above the first one to get the straps to lay correctly. Usually that's done when there's a new driver who is taller than the previous driver and cutting the cage apart isn't an option. Such tubes usually only run from the main hoop to the diagonal and rarely all the way across. Some sanctioning bodies either don't allow this, or take a dim view of it because of the way that the belts will load the diagonal tube in a crash.

 

[littlevulture]

Man that's interesting, not something that would have even been on my radar. Makes sense though now.

 

[aztoyman]

The harness installation instructions say 0 to - 20 degrees from horizontal with -10 degrees optimal and short as possible back to the mounting points.

I CAN put another bar in but, It'll look like an 80's pickup gun rack. Well it IS an 80's pickup. Hmm

I haven't fully welded what I have in yet so I'm going to cut it loose and move it up. Yes it will be a bit of a pain in the ass. It won't be wasted tubing if I fit it properly. Moving up, it gets narrower so I need to shorten the tube. I'll use my cool tubing tools to mark the cut line.

I'm going to get everything else cut and tacked in before I try moving it. After the seats are positioned, I need to fit and tack in the door bars.

 

[aztoyman]

I salvaged pretty much the entire piece of tubing I originally bent for my attempted roof halo bar. All I had left was the two bends. I used the straight sections for seat mounting structure between the sill bars. Kind of. The trans tunnel is in the way.

I need to cut some 1/8" plates to weld in to reinforce the sheet metal tunnel. I'm going to have to bend up a piece of tube to run parallel to the sill bar and alongside the tunnel. On both sides. I need to mount the inner lap belts to it. I'll use the sill bars for the outer belts.

Here's an idea of how it is fitting up so far. Nothing is even tacked yet. The one set of seat rails is my "test fit" one so you can see what I'm talking about. The permanent ones are shorter and have less holes.

Just to add, You can see I have cut the top off of the original front mount where the stock seat, front mounting bolts go. I'll weld that structure to the tube. It's good solid structure to the cab floor. The back bolt holes are still there as are the seat belt mounting holes. The 2nd gen 4Runner buckets will still bolt in if I removed the PRP mounting rails.

 

[aztoyman]

Here's one of my cool tubing tools in action. Definitely can save on wasted tubing. Hopefully it helps me refit my harness bar.

 

[gnob]

my rear feet are basically sitting right on the floor. idk how tall you are but thr seat height was putting me into the cage

 

[ntsqd]

Seeing the riv-nuts in the battery box flanges have I mentioned the tool that a guy on Garage Journal, "Rattle-Snake", came up with for making a divit to set them flush? Mine looks like this:

Makes divits like these tests of the tool:

For those without access to a lathe you can still make such a tool by carefully selecting the ID, OD, and length of some steel spacers (McMaster.com, possibly local hardware store), and then back them up with a heavy flat washer on the female side. Like this:

OD on the male side should be slightly larger than the OD of the riv-nut flange. You don't necessarily want the OD of the short spacer in the female side to be a close match to the OD of the male side. Make the difference more than 2X the thickness of the metal you're going to be using it on. I'd say at least 3X and perhaps as much as 6X the thickness.

 

[aztoyman]

@gnob the seat height was definitely a concern and why the rear seat mounting holes are below the tube. It's less than an inch above the floor. The cage is pretty close to the roof. My thumb barely fits between the top of the tube and the roof skin. Maybe 1/2". That's also why I'm not running a roof diagonal bar over my head. I can position my wife's seat away from the diagonal bar. Plus she is shorter.

I put the front mount on top of the tube because it matched the tilt of my original seats. I compared the feel to a flat base and the tilt was definitely more comfortable.