I'm sure it doable, its just too bad manufacturers spend so much time/money to make things difficult. I know its safety stuff but give me a break. A wiring diagram would be such a time saver.

 

There is a wring diagram in the 3,000+ page maintenance manual that is available here on the forum... It's not too hard to figure out when you remove the seat... You'll see a wiring harness that runs to the seat accessories and a portion of that harness splits off to the female end of the seat belt. There is another set of wires that are attached to an actuator in the seat the tells the system that somebody's fat A S S is in the seat... Once you get the seat off, you can figure it out...

 

the wire to the seat belt chime is: brown

i have cut my brown wire to eliminate the seat belt chime (wires from the buckle area). this also will eliminate the seat belt symbol on the dash instrumentation.

as for this working when installing an aftermarket seat... i can't answer that one.

 

The female end of the seatbelt buckle is bolted to the side frame of the seat. This attachment point acts as a ground for the circuit. It's really a pain in the butt to fabricate this thing so it all works after you replace the seat...

Just buy yourself a Schroth 5 point harness and forget about the airbag, seatbelt lights that illuminate on your dashboard. They look really cool, kinda like a christmas tree... LOL.

 

... oh yeah ... forget about my brown wire thing ... that won't help w/o the seat. duh.

 

Ok, so you recommend forgetting about trying to use the factory belt? You know, I would tend to agree that going with a harness is a lot less painful than trying to fabricate all the stuff to make the seatbelt work with an aftermarket seat.

Other than the airbag and seatbelt lights, is there any negatives to going this route? Will the ecu limit performance?

 

I'll look at cutting the wire with or without the seat. Thanks!

 

you can access the wire from the back side of the seat (put seat all the way forward & up)... the long wire harness is clipped onto the back of the lower seat edge. undo the 2 clips that attach wire to the frame (no need to pull seat) ... cut plastic sheathing and expose brown wire... snip and you are good to go. no chime for me.

 

No problem using the OEM seat belt with regards to the ECU. You can always just disconnect the entire harness under the seat and save it if you ever go back to the OEM seat.

It's still going to be hard attaching the race seat, you'll probably have to fabricate a bracket to adapt it to the OEM floor rails. I had to make long adapter plates and bolt them into the floor, then attach the race seat to the new rails. Either way you're looking at a good weekend of work.

 

Where is the best place to attach the harness?

The brackets shouldn't be too difficult, I can get my shop tech to build anything. I know universal brackets are available... are they worth buying or is it best to do it from scratch?

Thanks!

 

Well I couldn't use the universal brackets because it raised the seat too much for me to be comfortable with my helmet on... So, I built a bracket that bolted the seat directly to the OEM bolt holes. Works great for my purposes, but not perhaps for a normal street driver.

 

I've seen your harness attachment technique in your gallery. Looks like your bolting to the rear bulkhead. Is this correct? Because my seat will only be used for track days, do you have any other ideas?

 

The top 5" of the crossmember is a very sturdy steel beam. below that down to the floor is only a thin piece of sheet metal. I wouldn't bolt anything into the sheet metal, especially a shoulder harness. Aside from that, there really is no other place to safely attach the eye bolts for the harness.

Like I said in the earlier post, this process takes some fabrication.

 

Understood.

I'm looking at a used Sparco (not sure what model) out of a buds Mitsu race car. If it fits I will most likely buy it.

 

What about buying a factory seat out of a wreck and cutting the foam enough to lower it? I talked to a friend today who did this on his Miata. I want to consider all options before I buy anything.

 

It will still weigh about 60 lbs though.

 

Understood. I'm considering this direction because I found Limited seats for $165 plus shipping. I could have the seat bottom modified and then just bolt it back in place... no screwing with brackets/harness stuff. Or I might try an find a base seat so I can eliminate the electric stuff.

 

I have run standard and full race seats in road cars and the success really depends on what you are trying to achieve, more lateral support, weight saving or both.

There is no doubt that a proper race seat and harness feel much more secure on the track (and the road for that matter!) and allows you to concentrate on operating the controls rather than keeping yourself in place. I find you get a feel more directly connected to the car too.
However, I don't find the stock seats particularly bad for occasional track use; a bit more lateral support would be nice, or more importantly the option to fit full harnesses. But they are much more practical than racing buckets for everyday use - sliding over the side bolster of a race seat to get in and out is a real pain, not to mention sitting on the harness release buckle! A harness is also very restrictive for road use - just think how many times you reach forward to adjust their radio, open the glove box or lean forward at a junction for a better view around a parked car etc. before pulling out. If your harness isn't tight enough to prevent you moving then it will not retain you properly in a crash anyway - thats why we now have inertia reel belts with explosive tensioners. Not all race seats lend themselves to use with the stock belts since the side bolsters prevent the belt from contacting your body properly. You may fine a seat that will work though. The belt fit is something you also need to consider if you are going to lower the seat significantly, since the belt will tent to rub across your neck rather than your shoulder.

The best compromise seats I found for track and everyday use are the Recaro's I fitted to the 911 . They have deep bolsters and harness slots but still have rake adjustment and a quick release tilt - they aren't particularly light or cheap though. It is one area on the car where I have sacrificed added weight for convenience and comfort.
I will consider changing my stock seats in the Crossfire but mainly to gain harness slots so I can snap in a harness for trackdays. First I am going to look at getting the headrest area re-upholstered with slots in.

In terms of fitting a harness the only options for the rear mounting(s) I see are the bulk head, like HDDP has done, or fitting a brace between the rear turrets and fitting the straps to that.

All things considered I would stay with the stock seats if the car is your daily diver and you are just doing occasional trackdays. Otherwise I think you will be creating a marginally better track car and seriously compromising a very nice road car, and thats coming from someone who is prepared to put up with a fair amount of automotive inconvenience for the sake of performance - I used to drive my Sylva Striker (think Caterham 7 without the creature comforts!) everyday all year round it no weather equipment! But its your choice.

Here are the Recaro's in the 911:


Oh and if you do rip out your stock seats they can be put to good use elsewhere. I'm actually sitting on my old 911 seat to type this right now...

 

Woody,

I guess I should have been more clear about my requirements concerning a seat. I only do 2-3 track events per year. As a result, I don't want or need to do away with my factory seat. Its just that I'm 6'2" and I can't get in my car with my helmet on, therefore I need to drop it at least 1". Also, I have adjusted it as low as it will go and there is simply no way to get enough head room. So, my first thought was to get a race seat for track days only... I always travel with friends so one of them would haul the seat and I would install at the track. This is the reason that I am also seriously considering buying a used XFire seat and having the lower seat pad modified enough to get more head room. Maybe a base seat without electric adjustments would be a good path?

 

Sorry, I probably didn't read far enough back through the posts, just went on the thread title! Yes, a base seat without all the motor gubbins may be worth a look - failing that you'll have to get a Roadster.