What is the purpose of the hump underneath the front seats?

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Lake Forest CA
Not fond of Land Cruiser seats at all. I am 5.11 and weigh 260. Tying to install Range Rover seats to be so i can have the extra seat adjustments, comfort, the bolsters and also heating. Another problem is that the original seats dont slide back as much. But, in order to achieve the optimum position of the seat, i will have to cut out that hump/ridge. The question is..does this ridge have anything to do with structural integrity of the cabin or its there only for the seats to be mounted on given the floor board is quite low. Appreciate your help.

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My intuition tells me that that floor brace contributes to the structure integrity and safety of the floorpan, as well as providing strong points for the front seat mounting bolts.

If you do relocate the seat mounting bolts, make sure you do it as well as OEM if you want your seat to hold 260 lbs in one place during an accident.
 
Being that these are body on frame vehicles I wouldn't be overly concerned about modifying that. It likely does firm up the cabin and maybe you can drill the spot welds and remove it. But add some plate below like an 1/8th inch strap and maybe the same above to sandwich the sheet metal like they do for role cages and then bolt through for the seat. Not a structural engineer but the front seat is held in by 4 bolts which are held by small metal tabs from your seats. That to me seems more like a weak spot than that hump.

It's not a bad idea to overbuild just to be safe.
 
Being that these are body on frame vehicles I wouldn't be overly concerned about modifying that. It likely does firm up the cabin and maybe you can drill the spot welds and remove it. But add some plate below like an 1/8th inch strap and maybe the same above to sandwich the sheet metal like they do for role cages and then bolt through for the seat. Not a structural engineer but the front seat is held in by 4 bolts which are held by small metal tabs from your seats. That to me seems more like a weak spot than that hump.

It's not a bad idea to overbuild just to be safe.

Totally agree with you. The body-on-frame setup means that ridge isn’t doing much for structural integrity anyway. My buddy’s an engineer used to design medical devices for J&J—so he basically took over the whole project for me. He already ripped out the ridges and mounted the driver’s seat straight onto the floor pan. Had to drill some holes, though, so now we’ve gotta make sure there’s no chance of leaks or moisture sneaking into the cabin. Plan is to fully waterproof the pan, both top and bottom, and fill those drilled holes with silicone to seal them up.

The seat t’s insanely comfy. My goal was to drop it as low as possible and get that sedan-like driving feel. We’re pretty close! Arms are straight out, horizontal to the wheel, and I can still see a little bit of the hood—exactly what I was going for. Plus, with the Range Rover seats, I can always adjust the height if needed.

We also mounted the seat a bit forward compared to the OEM spot. That gives the back some decent legroom if the seat’s pushed forward. Slide it back, though...legroom’s gone but I’m good with that

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Man those look fancy. I am looking for seats for my pickup. Truck is so narrow I struggle to find comfort and rails close enough together to neither hit the door or the trans tunnel.

You are going to like thar adjustability I am sure.
 
Man those look fancy. I am looking for seats for my pickup. Truck is so narrow I struggle to find comfort and rails close enough together to neither hit the door or the trans tunnel.

You are going to like thar adjustability I am sure.
Do you wanna consider using the seats? I removed from my 80 series.?
 
Do you wanna consider using the seats? I removed from my 80 series.?
I actually already have extras that came with mine I cannot give away. They are too wide still. Same with sequoia seats. Apparently back in 79 the human race was more narrow.
 
Looks like I'm too late, but found this:

"Driver and passenger seat are mounted on transverse steel rails,[10] not bolted to the floor as per the standard configuration.[11] In a side impact these transverse rails allow the seats to crush a reinforced center console designed to absorb additional energy.[12]"

Link: Side Impact Protection System - Wikipedia - https://en.m.wikipedia.org/wiki/Side_Impact_Protection_System#:~:text=SIPS%20consists%20of%20a%20reinforced,b%2Dpillar%20absorb%20it%20all.
 
Looks like I'm too late, but found this:

"Driver and passenger seat are mounted on transverse steel rails,[10] not bolted to the floor as per the standard configuration.[11] In a side impact these transverse rails allow the seats to crush a reinforced center console designed to absorb additional energy.[12]"

Link: Side Impact Protection System - Wikipedia - https://en.m.wikipedia.org/wiki/Side_Impact_Protection_System#:~:text=SIPS%20consists%20of%20a%20reinforced,b%2Dpillar%20absorb%20it%20all.

It's OK. His buddy is an engineer. Used to design anal probes or something :meh:


This bit looks extra specially engineered
 
It's OK. His buddy is an engineer. Used to design anal probes or something :meh:


This bit looks extra specially engineered
I wasn't going there but it looks full sketch to me 🤷‍♂️
 
I actually already have extras that came with mine I cannot give away. They are too wide still. Same with sequoia seats. Apparently back in 79 the human race was more narrow.
Lol. Narrow is one way to put as opposed being wide.
 
Looks like I'm too late, but found this:

"Driver and passenger seat are mounted on transverse steel rails,[10] not bolted to the floor as per the standard configuration.[11] In a side impact these transverse rails allow the seats to crush a reinforced center console designed to absorb additional energy.[12]"

Link: Side Impact Protection System - Wikipedia - https://en.m.wikipedia.org/wiki/Side_Impact_Protection_System#:~:text=SIPS%20consists%20of%20a%20reinforced,b%2Dpillar%20absorb%20it%20all.

Basically, this minimizes that chance that the seat (and its occupant) becomes part of the crush zone during a side impact. Preferentially, the center console area crushes first. Very ingenious. You notice that the rail is still in place on the center console on the OP's truck? Yep, it is now strongest part of the floor. :doh:

What the OP did is make sure he and his front passenger are the first part of the crush zone during a side impact. :bang:

IMHO, If this vehicle ever gets sold, there needs to be a massive disclaimer put on the vehicle because it is now compromised.
 
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Yea right, great job. Those little boltsies and spacers and large area washers will keep the seats in place in the event of a collision 🙄.

Secondly, straight arms? Yea, great idea in a head on collision. Bent arms are better. Same as for steering, straight arms have very little range of motion vs bent arms.

Anal probe engineer, yup, someone is getting ass ****ed by insurance when it goes sideways!
 
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I had to deal with those humps too during my LR3 seats install. Took a 2# hammer to them so that my adapter can sit flat!

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I had to deal with those humps too during my LR3 seats install. Took a 2# hammer to them so that my adapter can sit flat!

View attachment 3790719View attachment 3790722
Better than removal.

If I was required to deal with this I would simply cut the top off, get the side heights as needed then weld a new top back on with captured nuts. Just like the factory set-up.
 
Better than removal.

If I was required to deal with this I would simply cut the top off, get the side heights as needed then weld a new top back on with captured nuts. Just like the factory set-up.
agreed, that approach is the best way to go. I might still go that route now that the seats are proving themselves to be very supportive for my body. Mind you, it's been 3+ years since the install took place :flipoff2:
 
Sh¡t stirring aside, even adding some structural, square washers under and over the floorpan to sandwich it between two structural washers to prevent bolts tearing out in an accident would be a big improvement.

Still, not awesome, but an improvement.

Something like below. A tiny cost for some improved safety.
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