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Discussion Starter #1
i also obtained a set of the Kansai seat slider rail all-in-one assembly from Japan.

Assembly is solid and very well designed. Great fabrication and precise construction.
Only issue wih these are the mounting tabs for the seat width are exactly 395mm tight.
These rails were specifically designed for the Recaro SPG/TSG/RSG seats which has a 395mm seat base width.

The mounting tabs are bent in with a slight offset to create the 395mm width. If Kansai had left the mounting tabs straight and vertical, there would be at least 410mm in mounting width opening up the possibility of many other seat options with varied seat widths.

Because of this, I have sent my Kansai rails to my fabricator to cut the mounting tabs off the rails, cut new identical tabs with no offset and reweld the new cutout tabs back into the same position on the rails to create a 410mm mounting width. Any gaps can be filled with spacers/washers between the tab and seat. I have emailed Kansai to see if future rails that are ordered could have the option of vertical tabs without an offset to be able to use more seat options.

The other challenge will be that the two sliders have independent unlocking/locking levers. Unlike our stock slider with the unlock lever being a one lever system, I will try to figure out lever extensions to make access to the levers more feasible.

But the Kansai rails do move the sliders to the side of the seat instead of the OEM sliders under the seat. This way, you drop the seat about an inch.

 

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Discussion Starter #2



http://imageshack.com/a/img922/5964/KJHXZ2.jpg[/mg]
[img]http://imageshack.com/a/img921/2203/c6lkiw.jpg

 

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Discussion Starter #3
Btw, the reason why i am widening my mounting tabs is because my Sparco Pro2000 seats have seat base width of 400mm.

I could have just bent out the tabs 2.5mm at each tab but I think it would a little ghetto with the top of the tabs flaring out. I guess I could have bent the flared out tabs back vertical but I thought if I was going to do this, I might as well do it right.... :)
 

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Great project, thanks for sharing.
Excited to see the final product!
You're going to be so comfortable you're not going to want to get out of the seats!


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I was leaning towards getting a Sparco seat... but now if I were to get the rails, I would go with the SPG or RSG
Yes better wait... I tried both the Recaro and the sparco and the Recaro are very similar so just go the safest route... I'm planning to order the rails anyway so we will know if they work with the sparco or not.. If they don't I will simply order the Recaro

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Interesting.... Just looked at Sector111 carbon fiber seat and mounting bracket. I really need to lower my seat some as I an restricted on head rotation to the left with a helmet.

How easy is it to swap seats? I may just swap seats on track days if it only takes an hour to swap.

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Interesting.... Just looked at Sector111 carbon fiber seat and mounting bracket. I really need to lower my seat some as I an restricted on head rotation to the left with a helmet.

How easy is it to swap seats? I may just swap seats on track days if it only takes an hour to swap.

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Swapping seats is easy....how fast you do it depends on how many (or few) dings you want on the CF tub ledge on the door sill... ;)
 

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Interesting.... Just looked at Sector111 carbon fiber seat and mounting bracket. I really need to lower my seat some as I an restricted on head rotation to the left with a helmet.

How easy is it to swap seats? I may just swap seats on track days if it only takes an hour to swap.

Sent from my Nexus 6 using Tapatalk
If each seat is attached to it's own seat rail, it's a piece of cake. Four torx bolts and about five - ten minutes work.
 

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Swapping seats is easy....how fast you do it depends on how many (or few) dings you want on the CF tub ledge on the door sill... ;)
Yup! you don't want to rush the process... I took my time to take the seat out, just to make sure I don't put any scratches on the CF tube :nerd:
 

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Discussion Starter #11
Received the Kansai rails back from my fabricator Friday.
Reviewing the replay, he cut off the original offset mounting tabs that were only 395mm wide. He then cut new mounting tabs to match the exact pattern of the original tabs except without the offset. This then created a 410mm mounting width. He welded on the new tabs and repainted it.

I initially tried to mount my Sparco seat at the lowest rear hole but the side of the seat makes contact with the slider lever at that mounting point. So, I went one hole up and it clears. Remember that the Kansai rails were developed and made specifically using the Recaro SPG seat with a 395mm mounting width. But at the second mounting hole in the rear and the 3rd mounting hole in the front creates a good mild recline angle. I will see how this configuration works first and then maybe make adjustments in the front mounting hole. The bottom of the seat in the rear is 1.75" and it feels like you're sitting on the floor. i am told I can remove the seat cushion to sit even lower.

I am receiving v2.0 of the Brey Krause mounting brackets on Monday so I have to test those for final seat position for final production piece. I will then mount the Kansai rails and go from there.... :)




 

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Oh OK.. I'll report how the rails like the sparco Rev.. I ordered them and waiting for delivery

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Discussion Starter #16
BK Mounting brackets? are these for the seat harness?
I am doing two seperate projects...

1. BK side brackets to be used with stock sliders and be able to convert to race seats. [email protected] had to tweak the original prototype I tested a few weeks ago. i am receiving v2.0 tomorrow to test fit with the stock sliders.

2. Kansai low position seat rails. Chose to fab and weld new mounting tabs that had wider seat base width of 410mm to allow me to mount my Sparco seats.

I already have the Kansai harness bar ready to go once I have everything to test.
 

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Doc, I'm putting together a cost estimate to do a 5 point harness system for my car (drivers side only). Where did you order the Kansai from and cost? Also, there doesn't appear to be a location to add the 5th point too. Do we have to add the BK 5th point bar? Is it even possible?

Thanks
DrPyro
 

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Discussion Starter #18
Had a chance to put the Sparco seat and Kansai rail assembly in the car this morning. Will definitely need to rethink this one as I ran into some barriers for the ultimate lowest seat position.

Issue #1: Firstly, seat height. Because the Sparco Pro 2000 has a 400mm seat width base, I had to modifiy the seat mounting tabs to move the seat mounting width on the Kansai rails from a tight 395mm to about 408mm and then use some spacers to make up the difference.

However, the rail slider lever mechanism on either side of the seat pinches in to 395mm as well preventing the Sparco 400mm to fit in between both lever mechanisms. This means I could not use the lowest mounting hole in the tab in the rear which is about 1/2" lower than the second hole which i used. In the end, though, with the 1" thick Sparco seat cushion, I am surpringsly sitting higher than stock height at lowest setting, actually higher than the BK bracket even with the Sparco seat cushion as well.



If you use the Recaro SPG, which these Kansai rails were specifically designed with and for, then you could probsbly use the lowest holes on the rails, dropping you about 1/2".

Issue #2: Seat slider......major PITA to use especially on the center console side. You have to release two locking levers to move seat rail. I understand Kansai's intention of turning the sliders 90 degrees perpendicular to get a lower seat position but the lock levers are hellish to manipulate.




But, more importantly, because of the shape of the harness lap belt bolt holes on the rear of the rails, this limits the slider from moving all the way back.



Because the seat is ~5 in from the rear partition, the passenger is scrunched forward and taller drivers will not fit. This was a problem I had with v1.0 of the BK brackets and had [email protected] move the mounting holes 3in to the rear to maximize seat transfer on the rails and leg room. In order to make the Kansai rails to allow maximum seat position forward and more importantly back, the mounting tabs will need to be redesigned to move the holes about 3 inches to the rear in an offset tab. (I'll have my fabricator work on this over the Winter)


 

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Discussion Starter #19
Here are comparison pictures of the Kansai rails and the BK v2.0 brackets at two critical clearance points at the top of the seat to the harness bar bracket and bottom of the seat to the CF tub jutout....


 

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Discussion Starter #20
Food for thought...

1. On v3.0 final version of BK brackets, [email protected] will optimize the mounting holes by lowering the holes another 1/4" as there is slightly more clearance from bottom of seat to top of rail bolts.

2. I have ordered the "flat" Sparco seat cushion that is supposedly 5/16" thick instead of the >1" thick stock cushion seat so we'll see.
3. I also ordered some 1/4" neoprene material that they use for motorcycle seat cushion and will see if I can cut to shape a replacement seat cushion and then wrap it with some spare Alcantara I have laying around and see how that works as well.
 
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