Adapting the S12 floor to mount the seats low. Ideas?

Started by sunny1600 · Feb 21, 2013 · 14postsSMF 2010–26

sunny1600Feb 21, 2013, 3:06 am · #1

Hi guys,

I need to mount my aftermarket seats lower so I am looking into the options to adjust the floor and lower the seats.

1. Sidemount instead of rails mounted underneath the seats
2. Adapt the floor bulge to be able to mount the seats lower.

This is what I have in mind atm.
Lets hear your thoughts and idea's.

posted image

This bulge needs to be cleared, and that chassis beam? also to be able to realise a lower seat position.

Second step is to modify the floor and weld in new parts.
I am thinking about doing it this way. Off course welded properly.

Will this be good enough to mount the seats and will this strengthen/ not compromise the integrity of the chassis?

I_heart_VVLFeb 21, 2013, 10:50 pm · #2

Here's one that looks a bit cleaner, it shouldn't be a problem if its braced like that.

posted image

200srdriftFeb 22, 2013, 6:12 pm · #3

thats too much work for an s12 lol.... hammer it flat and remount the bolt brackets lower on the slide rail.

DjayS12Feb 22, 2013, 6:39 pm · #4

200srdrift on 06:12:41 PM / 22-Feb-13thats too much work for an s12 lol.... hammer it flat and remount the bolt brackets lower on the slide rail.

It would be nice if that was that easy. The thing is the rail bolt on the little frame that follow the shape of that big bulge that make it impossible to be seated super low. So you can hammer the bulge like you said, but then there is a custom frame that need to be fabricated with two not welded to it for a rail to bolt on.

I wonder how tall the OP is. I'm 5'10 and with the stock seat and an helmet my helmet is hitting again the roof. I tried fitting a bride superlow seat before and I couldn't really fit the seat much lower than stock. I took the carpet off the roof and it doesn't help. In my case I'll get rid of the power sunroof eventually. The notch power sunroof take off about 1 1/2'' of clearance for the head... now I can't tell about his GP. Does it have a sunroof? if yes what kind?

ArroFeb 22, 2013, 8:10 pm · #5

Yeah stock seats are pretty low as it is, aren't they?

200srdriftFeb 22, 2013, 9:16 pm · #6

DjayS12 on 06:39:18 PM / 22-Feb-13but then there is a custom frame that need to be fabricated with two not welded to it for a rail to bolt on.

didn't understand how you wrote this.... im really looking to drop my race seat too. im only 5'7' and im almost hitting the roof.

ArroFeb 22, 2013, 9:53 pm · #7

I don't understand this... I'm 5'8" And I feel perfectly seated in my S12, and I have factory S12 seats. I also don't suffer from short-torso, long-leg issues. I have a balanced body length.

DjayS12Feb 22, 2013, 10:23 pm · #8

200srdrift on 09:16:15 PM / 22-Feb-13didn't understand how you wrote this.... im really looking to drop my race seat too. im only 5'7' and im almost hitting the roof.

Ok what I mean is that you are correct that the bulge can be hammered down.

Now if you hammer that bulge, it don't change a thing about the seat rail mount, as they are on some sort of transverse reinforcement that follow the curve of the floor pan. It also follow the shape of that bulge.

The proper way to do it would be to cut off the section of the reinforcement up front, hammer down the bulge and fabricated a new reinforcement that will replace the old ones. This custom reinforcement should have two threaded insert to bolt a seat rail on (just as the one you removed had).

I can't see a way to explain it clearer than this. Here is a picture of the said frame:
posted image

Lol Arro I'm not difform either. But I believe the notch power sunroof take more room in the roof than the sunroof of a hatch... The reason I believe so is I saw pictures of the same rollbar I have (autopower) in a hatch, the roof fitment was poor.. at least 1 full inch between the main loop and the roof, in my car it fit 1/4'' away from the roof.

200srdriftFeb 23, 2013, 12:29 am · #9

Arro on 09:53:02 PM / 22-Feb-13I don't understand this... I'm 5'8" And I feel perfectly seated in my S12, and I have factory S12 seats. I also don't suffer from short-torso, long-leg issues. I have a balanced body length.

i dont have the stock seat i have a omp's. it mounts higher with my universal mounts so i need to adjust the sliders lower.

DjayS12 on 10:23:21 PM / 22-Feb-13

thats the same as what i was thinking but still using and modifing the stock sliders

ArroFeb 23, 2013, 12:58 am · #10

That's possible about the sunroof, since it retracts INSIDE the car, whereas the hatch just has a pop-up roof.

D-sport S12Feb 24, 2013, 9:59 pm · #11

My bride sits low enough, don't even come close to the roof and its on stock sliders. I'm about 5,11" to

200srdriftFeb 25, 2013, 7:40 pm · #12

D-sport S12 on 09:59:19 PM / 24-Feb-13My bride sits low enough, don't even come close to the roof and its on stock sliders. I'm about 5,11" to

Post a pic.

D-sport S12Feb 26, 2013, 12:39 am · #13

Will do tomorrow

D-sport S12Feb 28, 2013, 6:34 pm · #14

Best picture I could take with my phone, by myself. This is stock rails with sidemounts

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