The truth about GT3 seats for tall drivers

[Mike_Yi]

Originally Posted by mmuller

I bought 2 Recaro SPG's (non XL). They came with the stock Recaro sliders and adjustable side mounts. I then took the BK R-9040 Seat track adapter kit to mount the sliders to the floor and the mounts to the sliders. I mounted the seats as low in the brakets as they could go.

By doing this I gained around 3 inches of seat drop. Where I used to look through the top of the windshield, I now look through the middle to lower half of the windshield.

That's pretty much what I've decided to go with Mmuller. I sat in a Boxster with Pole Position seats + sliders and had much more headroom. If you look at the BK brackets, they have more adjustment holes for reclining more too. I've been told that the BK brackets will let you lower the seat even further, though I have come to trust those people less now. I've also read (in only 1 place) that the Sparco slider is actually lower than the Recaro slider. BK's brackets work with the Sparco slider. I have to call BK tomorrow to ask them about that. I'll let you know what I find out.

By any chance do you still have the stock seat around? If so, could you do what I did (first measurement I described) to measure to see just how many inches lower the SPG is from the stock seat? It would require you to pull the Recaro seat to get a really accurate measure, but it would be great info for people like us.

Originally Posted by johnsimion

Is the vertical adjustment of the stock seat limited by the electronic whatzit that's under the driver's seat? If so, can the whatzit be relocated to under the passenger's seat? I am just looking for an inch or two additional clearance from the rollbar on the driver's side (my passenger is 5' tall and height isn't an issue). I can't see investing $1500 to $2000 for a couple of seats for a 10 year old car.

Not that I can tell John. I looked at the stock seat pretty carefully. I was trying to figure out if there is a way I could modify it to lower it. It could be done. There is a piece of metal between the seat frame and the sliders. In the front it could save you about 3/4" to an inch. The problem is that in the back it would only save about 1/4" unless you actually modified the seat frame. Most of the space up front, I think, is for the shock that pushes the seat up when you are raising the seat. Us tall people don't care about that, so that could come out. It wouldn't help in the back though.

[mmuller]

Sorry, I no longer have the standard seats. I was so happy to get the seating position finally right that I was happy to let go of them.

If you want to retain the standard seat belt and buckle, you will also need to use the BK-9005 Tunnel side seat belt anchor. This gave me a mounting point at the tunnel for the buckle and allowed me to retain the use of the standard seat belt. The car has been through 2 state inspections and they always comment on the nice integration of how it looks.

I can tell you that there is no more than a quarter inch between the bottom of the seat shell and the floor of the cabin. I could go one notch lower, but I would have to machine the side brackets somewhat as the side hole for the harness would foul with the bracket.

[Mike_Yi]

Do you use a harness at all? BK tells me that if I go with that solution I cannot use the anti-sub strap mount bar. That kinda defeats the purpose of the race seat (other than for getting more headroom).

They tell me if I want to use an anti-sub strap mount bar, I have to go with the R-9075 side mounts with the stock sliders. That will cost me 5/8"-3/4" of headroom. I want to put in a 6-point harness for DE, but I need all the headroom I can get.

What to do? What to do?

[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.