The truth about GT3 seats for tall drivers

[mmuller]

I don't use a harness (not yet anyway) as my goal was to get comfort and safety first and then worry about track days, which is still on my to do list.

I looked at the anti sub brace just now. At least in my install, I dont see why it would not work. I dont have the BK side brackets however. Mine came with the seat and were supplied by the company I bought them from, but I can't recall who that was as it was over 3 years ago. I think it was Speedware Motorsports. I still dont see why they wouldnt work with the BK solution however

[Mike_Yi]

I talked to BK again. I was wondering if their R-9773 brackets would mount the Recaro seat directly to the floor. It won't. They don't have a solution to mount it without sliders (which seems odd to me). If I have to, I'll fabricate an adapter myself for track days to get that extra inch of clearance.

Anyway, while talking to them again, I found out that the R-9062 (which is for use with the Sparco or Recaro sliders) WILL work with the anti-sub bar. It's just the R-9062s and the sliders aren't drilled out for it. The guy I talked to was one of the engineers at BK and he told me that lots of people do it and it works well. So it's not a clearance issue, it's just that the parts need to be drilled. BTW, the BK guy was VERY helpful.

So what he said to do is put all of the hardware together with the seat out of the car. Determine where the sub mount bar should be located. Mark the holes. Take it all apart and drill the holes with a cobalt bit. Since the BK parts are made of stainless steel, you have to use a cobalt bit or you will go through a ton of bits trying to drill it out. Finally, put it all back together. The holes need to be drilled in the bottom of the seat side brackets, and in the top piece of the slider.

I ordered all of the stuff I'm going to need from Stable Energies. The guy I talked to there was also SUPER helpful. After I gave him the list of everything I was ordering, he offered to have one of his installers double-check to make sure that should all work. Of course I took him up on it. I should have all of it on Tuesday, so I'll update the thread with the comparison between the seats then.

[SilentThunder]

My carbon fiber seats are lower than the stock seats. They are GT3 design but smaller I guess. When I first installed them I had to re-adjust my rear view mirror due to the height difference. They are for sale, check the classifieds if your interested.

[Mike_Yi]

I've got an update! I got the Recaro Profi SPG XL, the BK side mounts (R-9062), Recaro sliders, BK adapters (R-9040), and the BK inner seat belt mount point (R-9005).

First impressions.....

• The Recaro seat is wider than the GT3 seat. I wear a 36" waist pants and though I fit in the GT3, it was snug. Not tight, but snug. In the Recaro, I fit very nicely. I'm touching on both side pretty well, but I don't feel wedged in anymore.
• To look at the GT3 seat and the SPG XL, they appear to have the exact same design for the sides of the seats. The Recaro has higher sides to the front of the seat, whereas the GT3 has more sloping sides up front.
• The Recaro will provide for much better visibility as it narrows again above the shoulder support. The GT3 is so wide up top that it block the view (think backing up). My wife didn't mind as she could just look through the hardness holes.
• Just to look at them, the Recaro seat looks lower (more later).
• The GT3 wins hands down in the ease of use category. The Recaro is a PITA to put together (more later).
• The Recaro seat is heavier than the GT3 because all the BK parts are stainless steel, whereas the GT3 side supprts appear to be aluminum.

Details:
Weights -
GT3 - 26
Recaro (w/all mounting hardware) - 36
Stock - 47.5

I decided to measure a bit more accurately this time for the height of the seat (where your butt goes). What I did was use a laser level in front of the seat pointing at the seat back. I levelled the laser level then used a tape rule to make the measurements. Here's what I found....
Measuring at the furthest rearward part of seat bottom:
Stock - 5 1/8"
GT3 - 5 7/8"
Recaro - 7 1/8"
Note: These measurements are DOWN from a fixed height, therefore, the higher the number, the lower the seat. You can see that the stock seat is the highest of the seats here by about 3/4".

Measuring 5.5" out from the back of the seat. This is where I estimated that the majority of my weight is placed on the seat, and an approximation of the lowest point of my behind in the seat. Here's the numbers"
Stock - 5"
GT3 - 4 7/8"
Recaro - 6 3/8"
Note: These measurements are DOWN from a fixed height, therefore, the higher the number, the lower the seat. You can see that the stock seat is actually lower at this point than the GT3 seat by 1/8". In my book, that makes them virtually the same. The Recaro is a whopping 1 3/8" lower than the stock seat here.

Next I subjected the Recaro to the same test I performed with the other two seats to determine how high I sat in the seat. I put the seat in the same position against the wall. I sat the same way in the seat, had my wife place a level on top of my head and mark where the bottom of the level touched the wall. I really was expecting almost no difference here. I was shocked to discover that in the Recaro I sit fully 1.5" lower than in either of the other two seats (which were identical in this test).

A couple of things here that I have to mention. The GT3 seat can be mounted directly to the floor using BK side mounts. There is no such animal for the SPG XL (at least not for the Boxster). However, I did determine that if I wanted to, I could drill the existing BK side mounts and it would bolt directly down to the floor. That would gain about an additional 3/4".

The BK R-9062 mounts have one bolt hole in the rear of the seat and three in the front. This allows you, in theory to adjust the tilt of the seat. When I initially put the seat together I put it together in the top hole which would give me the most tilt. When I tried to put the seat in the car, I had to have the seat about 8" away from the back firewall. If you care about this topic at all, it is likely that you can't give up that much leg room. I know I can't. The problem is that the Recaro seat is so tall that it hits the roll bars, limiting how far back you can put the seat if it is highly reclined. The upside is that of the three seats, it is the only one where the back of my head is actually on the seat. In an impact, my head would hit the back of the seat rather than the rollbar. Yeah!

Putting the Recaro seat together is a PITA! I initially put the side mounts on the seat, then mounted the sliders to the side mounts. Can't do it. You can't reach the rear slider bolt as it is right up against the bottom of the seat. So you have to put the sliders on the side mounts first (mount the sliders as far apart as possible - in other words, the side mounts should be in as far as they will go). Then I could mount the whole assembly to the seat. The instructions suggest mounting the adapters (R-9040) to the floor, the attaching the seat. No way. I don't think you can do it that way. I'm going to mount them to the seat, then mount the whole thing in the car.

I don't know what the hell Recaro was thinking. When they made the sliders, the bolts they included are so damn long that they come in contact with the adapter bolts. This means that you cannot slide the seat. I have to run out and get shorter bolts before I can put it in the car, which means I have to put the stock seat back in for a hardware store run.

The BK R-9005 adapters are not designed for the Boxster. The holes don't line up. They are supposed to go between the adapters and the sliders. I am going to drill a separate hole. Keep in mind that these pieces are stainless steel. Use a cobalt bit to drill them.

I don't have the seat in the car yet (see above), but I will post my impressions when I do have it in the car. Oh yeah. One more thing. By the time you buy the Recaro sliders and all of the BK parts, the Recaro SPG XL ends up costing almost exactly what the GT3 seat costs.

[Mike_Yi]

Originally Posted by Mike_Yi

I don't know what the hell Recaro was thinking. When they made the sliders, the bolts they included are so damn long that they come in contact with the adapter bolts. This means that you cannot slide the seat. I have to run out and get shorter bolts before I can put it in the car, which means I have to put the stock seat back in for a hardware store run.

Well, at least now I know what Recaro was thinking. They were thinking, "Hey. 20mm are pretty common, let's use those. They might be a bit long, but so what?"

I can't find any shorter than 20mm. I need like 12mm. I just got off the phone with my Dad. A friend of his suggested calling a Japanese motorcycle dealer for the cap screw.

[Mike_Yi]

I found 16mm socket head cap screws in 8mm. They work great and don't hit the other bolts at all. However, I'm on Day 3 of installing this seat, and it won't be going in today. The problem is that the BK side mounts and hitting the sides of the shell. That keeps the sliders and adapters pushed out pretty far. In fact, they are about 3/8" too far apart. The holes in the floor at 16" apart, and the closest I can get the holes in the adapters is 16 3/8". I've got to call BK tomorrow. I can, of course, grind down the part of the side mount brackets that are hitting, but I want to talk to BK before I go to that extreme. I don't know if I can even modify things enough to recover 3/8".

Needless to say, I'm not very happy with the whole process.

I did find that by mounting the seat in its full reclined position (top holes in the front), compared to mounting it in the full upright position (bottom holes in the front) makes you give up roughly 2 3/4" of leg room because of the top of the seat hitting the roll bar.

[Mike_Yi]

The Recaro SPG XL is finally in. It took my 4 days to finally get it in.

My problem with the brackets being too far apart in the rear was not because the side mount brackets were hitting the seat, but because the bolts attaching those brackets to the sliders were hitting the seat. This limited the amount of side-to-side movement on the sliders. My solution was to grind the head of the cap screws down at a 45 degree angle to provide more clearance. It did the trick. It was still tricky to get the seat in.

So the final results are that the Profi SPG XL is definitely lower than the GT3 seat. It is not, however, lower than the stock seat. This is due entirely to seat position. I had the stock seat reclined quite a bit in the car. The SPG XL with the BK mounts is reclined much more than the GT3 seat, but it is still much more upright than where I had the stock seat. In addition, I lost approximately 4" of leg room because the SPG XL is so tall that it hits the rollbar, which prevents it from sliding back all the way. I remove the rollbar padding on the driver side to get a tad bit more room.

If you are looking for a seat for driving on the road that will give you more room, and you never intend to drive it on the track, you may be able to find a seat that gets you lower. I'd personally recommend doing the foamectomy on your stock seats though. AFAIK, the GT3 and the Profi SPG XL are the only seats with shoulder harness openings high enough for taller drivers. The GT3 seat is definitely NOT designed for tall drivers though. The SPG XL is. It just doesn't work great in a car with rollbars like the Boxster.

I hope this info helps other people. I would have liked to have had this info prior to buying two seat.