Now available for download: 86BUTTDROP lowering brackets for OEM seats

[timurrrr]

If you're taller than 6' and/or have a long torso and/or drive the car with the helmet on, you've likely experienced various degrees of issues with the headroom.

As a 6'4" guy with a tall torso myself, I always struggled a bit with my seating position during track days and autox. I had to sacrifice either the legroom, neck comfort or arm position. Every time after a track day my upper back would be tired, and every once in a while I literally needed a chiropractor appointment. I decided I had to figure out a solution.

Some people just switch to aftermarket seats. I'm a believer of the "either full OEM, or full race car" approach to the safety systems, so losing the airbag was not acceptable to me. Additionally, I wanted to keep the seat back adjustable.

The great news is that after some research I found a solution!
I designed and made a prototype mounting bracket for the OEM seat that drops the seat by 15 mm. (I believe it's possible to achieve 20 or even 25 mm below OEM, I'm currently working on a revised design to confirm.)

A couple of days ago I went to a track day where I tested the new seat position and immediately felt an improvement. I was able to improve my arm position and move my head more freely, my "look ahead" vision improved, and best of all I had no discomfort in my upper back the next day!

To lower the seat beyond the OEM range, I had to remove the sliders. There's still a bit of legroom adjustment through the height adjustment mechanism that is retained, in case another tall-ish person needs to drive the car.

The kit doesn't require any cutting or drilling of the OEM parts, and can easily be un-installed. Installing the kit is not harder than installing a bucket seat (I'd argue it's actually easier), and much easier than installing ND Miata Seat Lowering Brackets from Paco Motorsports.

I'm exploring the idea of offering a small batch of these brackets for sale.

October 2024 update: Designs for parts that you can order via SendCutSend are now available for download (for free) at https://github.com/timurrrr/86buttdrop

[timurrrr]

If you're interested in buying one, please post a response, including:

1. If your seat is "fancy, heated" or "basic, not heated"
2. The distance between the front of the slider and the front of the rail on the door side of the seat in your normal helmet-less driving position, in millimeters. See the picture below, in this example the distance is 60 mm.
3. If you're interested in helping me test near-final prototypes, or only interested in the "set and forget" product
4. If you have mechanical engineering background and can provide design feedback / suggestions
5. If you're located in the SF Bay Area

A very early estimate is $400 for the kit. Note that this is a low-volume product, so I'll need to pay extra for the parts fabrication, and also I want to at least break even on my R&D efforts. I have a day job, and am only offering this to the community because I see a problem that needs to be solved for some people, and I found a solution; not to become rich.
This is still cheaper than any aftermarket seat + mounting bracket combo that I'm aware of.

[timurrrr]

Forgot to mention: this kit is designed for gen2 seats only.
A similar product for gen1s might be possible, but I don't have time to look into that yet.

[nomtimesthree]

1. fancy, heated
2. Roughly 10mm, tight space to get an accurate measurement. Yes, I sit close to the wheel.
3. At $400 I'd be in the "set and forget" category. Would consider helping test and feedback if there was a discount.
4. No formal ME training.
5. NOT in SF Bay Area.

[norcalpb]

I have a Gen 1 but would be interested in testing if development ever begins to include 2013-2020 cars.

2nd Gen seats fit in the 1st Gen but I understand the rails might be different enough to make a difference.

Also located in the Bay Area.

[timurrrr]

Originally Posted by timurrrr

A couple of days ago I went to a track day where I tested the new seat position and immediately felt an improvement. I was able to improve my arm position and move my head more freely, my "look ahead" vision improved, and best of all I had no discomfort in my upper back the next day!

Just to set clearer expectation, for me (6'4") the 15 mm drop didn't fully solve the problem, but definitely made a significant improvement.

[sato]

Originally Posted by norcalpb

I have a Gen 1 but would be interested in testing if development ever begins to include 2013-2020 cars.

2nd Gen seats fit in the 1st Gen but I understand the rails might be different enough to make a difference.

Also located in the Bay Area.

Another subscribed hopeful.

[Yoshoobaroo]

Hell yes I’m in for a 15mm drop

[dragoontwo]

Interest here as well.

1. Fancy, heated.
2.
3. Willing to test.
4. No ME background, Aviation based mechanic.
5. See ↙.

[Ultramaroon]

Originally Posted by timurrrr

Just to set clearer expectation, for me (6'4") the 15 mm drop didn't fully solve the problem, but definitely made a significant improvement.

Every little bit helps us freaks. In 4 drop.

[OkieSnuffBox]

I'm not a tall guy, but I feel "on" the car in the 2nd gen vs "in" the car like my 1st gen.

Have you had a chance to see if you can more than 15mm yet?

Heated seat, '23 BRZ Limited.

[timurrrr]

Originally Posted by OkieSnuffBox

Have you had a chance to see if you can more than 15mm yet?

After a couple of iterations with a 15 mm drop, I'm awaiting production of a prototype that should give me ~25 mm drop.

I think I might be able to eventually get to ~30 mm... But beyond a certain point the more you drop, the more compromised other things get, such as ease of installation, structural rigidity and necessity to start cutting OEM stuff.

Originally Posted by Ultramaroon

Every little bit helps us freaks.

Absolutely!

[Racecomp Engineering]

FWIW I have 40mm drop seat rails on my 1st gen with Recaro SR7 seats (which I think also drop your butt a little) and the difference while driving is definitely awesome.

It is also definitely a compromise in terms of getting in and especially getting out. Parallel parked next to a curb requires some dexterity. Luckily I'm limber as heck but passengers sometimes complain.

15-25mm seems like a good compromise (though I regret nothing).

- Andrew

[Ultramaroon]

My headliner resembles an old floor mat.