I started a thread a while back about the tight seating with the Sport Seats. Those of us with a little too much junk-in-da-trunk (like me) have found the thigh bolsters to be a little tight for comfort.

It's actually not so much a problem of fat bottoms, but that the Sport Seats are the exact same ones used in the Japanese home market Skyline (the average Japanese male is about 5'4" and 140 lbs, the average American is about 5'11" and 187 lbs. - Americans are just bigger than Japanese, and most car companies fit bigger seats here).

I recently drove my car on a 1500 mile trip, and started wanting to claw my way out of the seats after about 4-5 hours. It's just too confining for me (6'0" and 200 lbs).

The problem is now solved! Today I found a simple and elegant solution. I took the car to a custom upholstery shop (I called several, to find one that has worked on seats in high end sports cars). While they have not worked on a G37 before, they have done similar modifications on other "Sport" seats (in Porsches) to provide more room. The same solution they have used on Porsches worked perfectly on the G37S.

The G37 Sport Seat has a rigid metal brace in each thigh bolster. It is a plate, about 1 in x 6 in, with a short supporting rod on each end. It is welded to the seat frame, and holds the thigh bolsters very rigidly at a nearly upright angle. If you push down and feel around in the thigh bolster, you can feel this metal brace just under the upholstery. The adjustable thigh bolster bladders also push against these braces, making for a very tight fit - it is rock hard.

The solution was simple: remove the braces. They removed the driver's seat, took the upholstery off the bottom, and just cut off the braces. Reassembled, the seat looks exactly stock. There is no way of telling that anything was done. But, sitting in it is just a world of difference! Instead of the thigh bolsters being rock hard and unyielding, the thigh bolsters are now resilient and pliable, and yield to the pressure of legs and a larger body on them. The driver's seat now behaves and feels like the bottoms of the non-Sport seats, or very similarly to the Sport passenger seat. The inflatable bolster bladders still work, but are just not as rock-hard, since they are now pushing against foam and upholstery instead of fixed steel.

Driving around today was a completely new experience. The seat is now actually completely comfortable, instead of just somethig to be tolerated in exchange for the rest of the benefits of the car. The back bolsters are unchanged, so one is still held in place "Sport" style, but without the confining pressure on the legs (I asked them to look into the back bolsters, but they cannot be played with because of the seat mounted side air bag).

For anyone who also feels the thigh bolsters are too confining, this is a simple and invisoble solution that completely cures the problem (I wouldn't be surprised if Infiniti might start doing this in the future, if they get enough complaints about the seats). If anyone is in the Philadelphia area, you might want to see Accurate Auto Tops and Upholstery, on Route 3 in Edgemont (near West Chester), ask for Mark.

 

Got pics?

 

The other solution - lose a bit of weight by toning. It's called exercise.

 

As much weight as you lose, when you ar 6'4" and in good shape (as I am), you tend to still be very "big"

 

I'm 6'3" and I'm in great shape. I don't have such a problem. I guess it depends on the body type.

 

Yeah, quite literally I have huge bones. No matter how much weight I lose at my size, im still going to be big.

 

Hahaha, that's exactly the phrase that my wife uses every time.
Edit: My wife is not big, but she thinks she is.

 

Its not really about weight bro when ur 6 feet tall and a beef eating American and just have a bigger frame than a rice eating Japanese shrimp - the seat's gonna be cramped for you. No reason to sacrifice your body frame and your manly physique for a fukcin car. at 6 feet and 200 lbs he is actually not "fat" at all that is just a meatier build but far from fat. Obesity at 6 feet tall is probably when you pass the 220 lb mark. If anything Infiniti fukced up by catering to the average Japanese man in an "average American" nation. Me myself I am 5 feet 11 inches and weigh in at 215 pounds and Im not fat by any means. Losing weight to fit into a car seat puts us at the same level as skanks who lose weight to get into music videos for $500 a video shoot and a rapper's **** in them. it just aint worth it. a 42k car should cater to the market.

 

Will someone strike a nerve here? This thread doesn't have strong enough opinions.

 

Lame. This comment is so played out.

This is probably the same guy who would tell you to go on a diet to get a better 1/4 time.


Come up with some new material.

 

Fine. I retract my remark.

Some people can be so hyper-sensitive.

 

even asians who live in asia and ones who grew up in the U.S. the ones who grew up in the U.S. tend to be taller and much bigger. i think the hormones in the meat products and milk have somehting to do with it...lol. i mean look at kids nowadays! there are some 6th graders who are just huge compared to when i was a 6th grader.

 

I still own a G35 coupe, but in my opinion, by removing those metal braces, you are setting yourself up for a collapsed cushion down the road.

The G's are notorious for crappy seat cushions, with everything from cracking leather to rotting foam underneath.

I had to replace my seat cushion and leather seat bottom early on in my ownership, and I weighed only 170lbs at the time.

I wouldn't be surprised if you encounter a collapse on the left side bolster in no time flat now that you did that alteration....
Good luck

 

I have to say, I am surprised and disappointed at some of the venomous and judgmental comments on this thread. When I first posted the comment and question about a month ago regarding the tight fit of the Sport seats, it seemed like several other ("American" sized) people also remarked that they found the Sport seats a little tight. I thought my post on my own solution to the issue would be helpful to others, rather than spark a disparaging debate on 'size'.

I didn't think this was a forum for 'better health for living', but on our cars. Yes, I've gained a few pounds (like 75% of American men) since graduating high school 30 years ago (yeah, I'm 'that old', I perfectly fit Infiniti's target demographic for the car). It's not a question of what is the 'right' size, but, what does a pretty much average size American guy do to comfortably fit into a seat designed for a Japanese body? The Japanese are simply smaller than most Americans. Most men in this country are not built like ballet dancers or gymnasts, with bodies the size of men in Tokyo. At maybe 10% over my 'ideal' weight, and maybe 5% bigger than the 'average' American guy, I didn't think it was unreasonable to want to comfortably fit in a $42k car (absolute weight has little to do with it; at 6'0", even if I starved, my hip width and skeletal structure still would not fit comfortably).

It turns out that the only structural differences between the Sport seat and the regular seat are the vertical metal brace I removed, and the inflatable bolster bladders. By removing the brace, it basically turns the bottom of the Sport seat into the regular seat, though it still has the inflatable bolster bladder which still works. The brace is a vertical member, it is not a load-bearing member. It is designed to provide lateral, horizontal support, not vertical weight bearing - it pushes against the thighs, not hold the weight of the driver.

You never know for sure what will happen long term with any mod. But, it seems that problems should not be any more likely than they would be on the standard seats without the extra brace. The thigh bolster on the seat does not bear any significant weight. The shop that did the work has been removing similar braces on Porsche Sport seats for years, and has never had any problems. As long as it doesn't offend anyone's sensibilities and catalyze another hot debate on body size and weight loss, I'll periodically post reliability updates on how the modified seat is holding up.

 

Agree with you 100% I am heatthy 6'1" 200 lbs work out and play hockey. I am just too wide for the seat. thanks for posting about this mod. I am currently working on loking for a shop to do this for me keep us informed on how it feels and if it causes the seat to wear prematurly.