Six-point race harness belt installation
Jul 4, 2005, 12:12 PM
#1
Six-point race harness belt installation
(Cross-posted to NorCalEvo.net.)
Before you begin
These instructions describe the installation procedure for a G-Force 6-point camlock 3" race harness; if you have a harness of a different type or manufacturer some of the instructions may not apply to you (however most harnesses of the same type from other manufacturers will be very similar). The instructions assume the presence of a harness bar, either a standalone unit (e.g. Sparco) or one attached to a rollbar/cage (the one seen here is the AutoPower race rollbar). Here, the harness is attached to stock factory bolt points and preserving the OEM seatbelt for street use. You may elect a different installation setup in which case some/most details here will not apply to you.
Disclaimer: I take no responsibility for damage to yourself or your car caused by improper harness belt installation. Nor do I claim that what is shown here is the best (or even correct) installation. If you are not comfortable performing this type of installation yourself, please take it to someone who is. Remember you are installing safety equipment, so the "usual" car-install warnings apply doubly: take your time, double-check everything, and if there's something you don't understand or can't figure out, get help.
Time required: if you know what you're doing and have all the tools and hardware on hand, installation can take as little as an hour (per harness set) but again, take your time and do a proper job.
Tools required
14mm, 17mm wrenches and/or sockets/ratchet
Torque wrench (and sockets)
Philips head screwdriver
Materials
- Harness belts (shown here is the G-Force Pro Series six-point camlock pull-down harness set);
- 3/8" or 10mm washers (one per harness set);
- If you elect to bolt the inside lap belt using the inside rear seat bolt, you'll need to replace that bolt with something longer (make sure you buy grade 8 steel hardware)...
- ... Otherwise (if you're bolting the inside lap belt to the seat where the factory belt buckle goes) you'll need to substitute a different endpiece on the inside lap belt that will fit alongside the OEM buckle; I used a bolt-end installation kit from Schroth (nevermind the warning label, it's designed to work with a 3" belt) which has a longer "tongue":
You need one Schroth bolt end per harness set so one kit is enough for two harness sets.
Preparing the belts for installation
Take the inside lap belt (the lap belt that's anchored near the center of the car), undo the belt from the adjuster (the metal piece through which the belt is laced 2-3 times), and remove the G-Force bolt end. The hole in the Schroth bolt end is actually a bit less than 2" across so you can't simply thread the belt through. Instead, fold it in half and thread it through:
Pull the belt through to where you want it to be, then work it so both edges are folded over (on the inside of where the belt will be looped):
Lace the belt back through the adjuster, keeping everything neat:
Before you proceed with installation, make sure you have all the belts and hardware you need:
Outside lap belt
To make it easier to keep the factory belt oriented the right way and avoid twisting it around, buckle it up:
The outside lap belt bolts to the same point as the end of the factory belt (seen here with my old Schroth Autocontrol harness belt):
Slide the rubber cover off and undo the bolt (again, the bolt end in the photo below is for my old Schroth Autocontrol belt):
The bolt is wider and smooth at the end to fit the factory bolt end, so the 3" bolt end will go between the factory bolt end and the car. I also added a washer to space the bolt end out a little bit to allow the bolt to tighten properly.
Make sure the bolt end pieces (both the 3" harness and factory) are turned and oriented the right way and tighten the bolt to 33 ft-lbs. You may elect to retain the rubber cover; I removed it.
Inside lap belt
You'll need to remove the center console to easily access the bolt for the inside lap belt. This is covered in many other installs (for example the rollbar install) and will not be detailed here. The inside lap belt (factory buckle) is bolted to the seat bracket. Bolting the racing harness to this point isn't ideal and with a racing seat (and a different seat rail/bracket) may not be possible at all, in which case bolting the belt to the car body with a steel backing plate welded in would be the preferred option.
Note the bolt end for my old Schroth harness in the photo below; the new belt will go in the same position. As you can see the new bolt end can only go on one side of the factory buckle "arm" due to how the latter bends; the little metal tabs that keep the factory buckle at the correct angle interfere with the G-Force bolt end which is why I fitted the Schroth bolt end.
Undo the bolt; on the driver's side, there will be wiring to the factory belt buckle to control the seat belt warning light; take care not to pull on it or damage it. (Presumably, shorting the two wires together will close the switch and keep the warning light off, though I wouldn't recommend tampering with it.) Unscrew the retaining washer and put the Schroth bolt end on the bolt, making sure it's turned the right way.
Reattach the bolt and torque to 33 ft-lbs.
Anti-submarine ("crutch") straps
Contrary to popular belief, the anti-sub strap does not hold you, unlike the other belts. Rather, its purpose is to strap the lap belt down and keep it from "riding" up in the event of an impact. This keeps the lap belt correctly positioned over your hips (which can absorb more force than other parts of your torso) and prevents injuries from "submarining" (sliding under the lap belt). As such, the strap is never tight against your "delicate" areas since it's anchored slightly forward of your body. Many true racing seats will have a hole in the bottom for ideal positioning of the strap; otherwise, the strap has to be looped over the front of the seat.
Five-point harness sets will have a single anti-sub strap; six-points, two. Some people prefer the latter for comfort reasons; in this particular case, two straps are ideal because they can be anchored using the factory seat bolt points; a single strap could be anchored either to the seat bracket or car body (with backing plate).
Undo the nuts holding the factory seat bracket:
Put on the anti-sub belt bolt ends, making sure they're turned the right way (tip: on my belts, the labels on the anti-sub belts face downwards when the belts are latched) and angled slightly inwards.
Tighten the nuts to 22 ft-lbs of torque. Important: pass the belt between the seat and the seat slider handle, otherwise the belts could pull the handle upwards under load and allow the seat to slide freely--not what you want during an impact!
Shoulder harnesses
The shoulder straps loop around the harness bar and therefore the bolt ends they come with are not needed (and should be removed).
With the G-Force harness belt, the left and right shoulder straps are identical. Before you tie them to the harness bar, thread them through the holes in the factory Recaro seat. It's much easier to thread the belts in "backwards" than "forwards" as getting the latch and tightening hardware through the hole--as opposed to just the belt and adjuster--can be something of a pain.
Attaching the belts to the harness bar is straightforward: make the belts are flipped over the right way, then bring the belt under the bar and loop over to the adjuster. Lace the belt into the adjuster; over:
Under:
And back around:
(You may wish to leave the belt partly laced until you've adjusted the shoulder belts to the right length.)
Adjusting belt lengths
With all the belts in place, slide and recline the seat to your driving position, and sit in it. Latch all the belts to the camlock and tighten by pulling on the rolled-up "grab" ends. (Always tighten the lap belt first, then the shoulder harnesses.) You'll likely end up with a lot of extra belt. Having a bit of extra is ideal as it allows you to easily buckle up the belt before tightening it, and allows for different drivers and seat positions. However you don't want too much extra belt because it makes it more difficult to tighten the belts properly. With the shoulder straps, you don't want the extra to be flapping in your face and interfering with your vision when you're out on the racetrack.
Use the adjusters to "shorten" the belts as needed. The anti-sub straps should shortened so that they are fairly tight around the front of the seat and securely holding the lap belt over your hips--it should not be possible to pull the lap belt up and out of position by tightening the shoulder harnesses. It may take a few attempts to get this right but it's important that you do, so don't rush.
If you don't ever plan on using the belts in any other car, configuration or with a different driver, you can tidy things up by trimming some of the extra belt length, though I have not (yet).
Factory belts
Make sure you can still use the OEM seat belts (assuming you've retained them). You may need to tuck the racing belts out of the way to do so. For practical and safety reasons you should generally use the OEM belts on the street and save the race harnesses for the autocross/track/dragstrip.
Done!
And now that you're securely belted in, go out there and break some lap records!
Before you begin
These instructions describe the installation procedure for a G-Force 6-point camlock 3" race harness; if you have a harness of a different type or manufacturer some of the instructions may not apply to you (however most harnesses of the same type from other manufacturers will be very similar). The instructions assume the presence of a harness bar, either a standalone unit (e.g. Sparco) or one attached to a rollbar/cage (the one seen here is the AutoPower race rollbar). Here, the harness is attached to stock factory bolt points and preserving the OEM seatbelt for street use. You may elect a different installation setup in which case some/most details here will not apply to you.
Disclaimer: I take no responsibility for damage to yourself or your car caused by improper harness belt installation. Nor do I claim that what is shown here is the best (or even correct) installation. If you are not comfortable performing this type of installation yourself, please take it to someone who is. Remember you are installing safety equipment, so the "usual" car-install warnings apply doubly: take your time, double-check everything, and if there's something you don't understand or can't figure out, get help.
Time required: if you know what you're doing and have all the tools and hardware on hand, installation can take as little as an hour (per harness set) but again, take your time and do a proper job.
Tools required
14mm, 17mm wrenches and/or sockets/ratchet
Torque wrench (and sockets)
Philips head screwdriver
Materials
- Harness belts (shown here is the G-Force Pro Series six-point camlock pull-down harness set);
- 3/8" or 10mm washers (one per harness set);
- If you elect to bolt the inside lap belt using the inside rear seat bolt, you'll need to replace that bolt with something longer (make sure you buy grade 8 steel hardware)...
- ... Otherwise (if you're bolting the inside lap belt to the seat where the factory belt buckle goes) you'll need to substitute a different endpiece on the inside lap belt that will fit alongside the OEM buckle; I used a bolt-end installation kit from Schroth (nevermind the warning label, it's designed to work with a 3" belt) which has a longer "tongue":
You need one Schroth bolt end per harness set so one kit is enough for two harness sets.
Preparing the belts for installation
Take the inside lap belt (the lap belt that's anchored near the center of the car), undo the belt from the adjuster (the metal piece through which the belt is laced 2-3 times), and remove the G-Force bolt end. The hole in the Schroth bolt end is actually a bit less than 2" across so you can't simply thread the belt through. Instead, fold it in half and thread it through:
Pull the belt through to where you want it to be, then work it so both edges are folded over (on the inside of where the belt will be looped):
Lace the belt back through the adjuster, keeping everything neat:
Before you proceed with installation, make sure you have all the belts and hardware you need:
Outside lap belt
To make it easier to keep the factory belt oriented the right way and avoid twisting it around, buckle it up:
The outside lap belt bolts to the same point as the end of the factory belt (seen here with my old Schroth Autocontrol harness belt):
Slide the rubber cover off and undo the bolt (again, the bolt end in the photo below is for my old Schroth Autocontrol belt):
The bolt is wider and smooth at the end to fit the factory bolt end, so the 3" bolt end will go between the factory bolt end and the car. I also added a washer to space the bolt end out a little bit to allow the bolt to tighten properly.
Make sure the bolt end pieces (both the 3" harness and factory) are turned and oriented the right way and tighten the bolt to 33 ft-lbs. You may elect to retain the rubber cover; I removed it.
Inside lap belt
You'll need to remove the center console to easily access the bolt for the inside lap belt. This is covered in many other installs (for example the rollbar install) and will not be detailed here. The inside lap belt (factory buckle) is bolted to the seat bracket. Bolting the racing harness to this point isn't ideal and with a racing seat (and a different seat rail/bracket) may not be possible at all, in which case bolting the belt to the car body with a steel backing plate welded in would be the preferred option.
Note the bolt end for my old Schroth harness in the photo below; the new belt will go in the same position. As you can see the new bolt end can only go on one side of the factory buckle "arm" due to how the latter bends; the little metal tabs that keep the factory buckle at the correct angle interfere with the G-Force bolt end which is why I fitted the Schroth bolt end.
Undo the bolt; on the driver's side, there will be wiring to the factory belt buckle to control the seat belt warning light; take care not to pull on it or damage it. (Presumably, shorting the two wires together will close the switch and keep the warning light off, though I wouldn't recommend tampering with it.) Unscrew the retaining washer and put the Schroth bolt end on the bolt, making sure it's turned the right way.
Reattach the bolt and torque to 33 ft-lbs.
Anti-submarine ("crutch") straps
Contrary to popular belief, the anti-sub strap does not hold you, unlike the other belts. Rather, its purpose is to strap the lap belt down and keep it from "riding" up in the event of an impact. This keeps the lap belt correctly positioned over your hips (which can absorb more force than other parts of your torso) and prevents injuries from "submarining" (sliding under the lap belt). As such, the strap is never tight against your "delicate" areas since it's anchored slightly forward of your body. Many true racing seats will have a hole in the bottom for ideal positioning of the strap; otherwise, the strap has to be looped over the front of the seat.
Five-point harness sets will have a single anti-sub strap; six-points, two. Some people prefer the latter for comfort reasons; in this particular case, two straps are ideal because they can be anchored using the factory seat bolt points; a single strap could be anchored either to the seat bracket or car body (with backing plate).
Undo the nuts holding the factory seat bracket:
Put on the anti-sub belt bolt ends, making sure they're turned the right way (tip: on my belts, the labels on the anti-sub belts face downwards when the belts are latched) and angled slightly inwards.
Tighten the nuts to 22 ft-lbs of torque. Important: pass the belt between the seat and the seat slider handle, otherwise the belts could pull the handle upwards under load and allow the seat to slide freely--not what you want during an impact!
Shoulder harnesses
The shoulder straps loop around the harness bar and therefore the bolt ends they come with are not needed (and should be removed).
With the G-Force harness belt, the left and right shoulder straps are identical. Before you tie them to the harness bar, thread them through the holes in the factory Recaro seat. It's much easier to thread the belts in "backwards" than "forwards" as getting the latch and tightening hardware through the hole--as opposed to just the belt and adjuster--can be something of a pain.
Attaching the belts to the harness bar is straightforward: make the belts are flipped over the right way, then bring the belt under the bar and loop over to the adjuster. Lace the belt into the adjuster; over:
Under:
And back around:
(You may wish to leave the belt partly laced until you've adjusted the shoulder belts to the right length.)
Adjusting belt lengths
With all the belts in place, slide and recline the seat to your driving position, and sit in it. Latch all the belts to the camlock and tighten by pulling on the rolled-up "grab" ends. (Always tighten the lap belt first, then the shoulder harnesses.) You'll likely end up with a lot of extra belt. Having a bit of extra is ideal as it allows you to easily buckle up the belt before tightening it, and allows for different drivers and seat positions. However you don't want too much extra belt because it makes it more difficult to tighten the belts properly. With the shoulder straps, you don't want the extra to be flapping in your face and interfering with your vision when you're out on the racetrack.
Use the adjusters to "shorten" the belts as needed. The anti-sub straps should shortened so that they are fairly tight around the front of the seat and securely holding the lap belt over your hips--it should not be possible to pull the lap belt up and out of position by tightening the shoulder harnesses. It may take a few attempts to get this right but it's important that you do, so don't rush.
If you don't ever plan on using the belts in any other car, configuration or with a different driver, you can tidy things up by trimming some of the extra belt length, though I have not (yet).
Factory belts
Make sure you can still use the OEM seat belts (assuming you've retained them). You may need to tuck the racing belts out of the way to do so. For practical and safety reasons you should generally use the OEM belts on the street and save the race harnesses for the autocross/track/dragstrip.
Done!
And now that you're securely belted in, go out there and break some lap records!
Jul 19, 2005, 12:01 PM
#2
People,
I used to work for Schroth USA, the company that imports, assembles, and sells every Schroth belt and hardware in the country. In no way is the sub straps safely mounted based on this install. Without getting into too much technical detail, the angle of the sub straps (the "Crotch straps") as the come off of the cam lock must be at least 45 degrees, which is close to pushing it, moreso should be 60 degress from the vertical plane. In order to accomplish this, you MUST HAVE the factory seat modified with a substrap hole to route the belts through. You may say, well, other than this, its OK, but this part is super critical. You are safer actually wearing the stock 3-point seatbelt than wearing a 6-point harness installed like this. Contact joe@hmsmotorsport.com for any additional questions. He has sold, installed, and adjusted belts for 15 NASCAR drivers, including Jeff Gordon, Mark Martin, etc., and he is known to nearly all NASCAR crew chiefs, as well as the director of safety. PM me if you need more answers.
Vtluu, this is in no way flaming you whatsoever. The other steps are well written and documented, and the bracket folding is perfect. About 90% of professional racers mount sub straps wrong, unsafely, and the education is just not there.
I used to work for Schroth USA, the company that imports, assembles, and sells every Schroth belt and hardware in the country. In no way is the sub straps safely mounted based on this install. Without getting into too much technical detail, the angle of the sub straps (the "Crotch straps") as the come off of the cam lock must be at least 45 degrees, which is close to pushing it, moreso should be 60 degress from the vertical plane. In order to accomplish this, you MUST HAVE the factory seat modified with a substrap hole to route the belts through. You may say, well, other than this, its OK, but this part is super critical. You are safer actually wearing the stock 3-point seatbelt than wearing a 6-point harness installed like this. Contact joe@hmsmotorsport.com for any additional questions. He has sold, installed, and adjusted belts for 15 NASCAR drivers, including Jeff Gordon, Mark Martin, etc., and he is known to nearly all NASCAR crew chiefs, as well as the director of safety. PM me if you need more answers.
Vtluu, this is in no way flaming you whatsoever. The other steps are well written and documented, and the bracket folding is perfect. About 90% of professional racers mount sub straps wrong, unsafely, and the education is just not there.
Jul 20, 2005, 12:57 AM
#3
Thanks for the info. As I said, it's not ideal (or even safe), and a stopgap measure since I'll be getting full race seats shortly anyway--with the proper sub-strap hole.
A bit of clarification regarding the sub-strap angle: does "45 degrees from vertical" mean the sub-strap is anchored behind the camlock, or in front (i.e. 45 degrees in which direction)?
A bit of clarification regarding the sub-strap angle: does "45 degrees from vertical" mean the sub-strap is anchored behind the camlock, or in front (i.e. 45 degrees in which direction)?
Last edited by vtluu; Jul 20, 2005 at 01:03 AM.
Aug 2, 2005, 11:34 AM
#4
It ends up being in front of the camlock, but ideally it should be directly under it. Sorry for the delay in the response, I forgot to subscribe to this thread. PM me if you have any questions.
Aug 4, 2005, 02:24 AM
#5
Thanks. What size/thickness of backing plate would you recommend for the sub straps? I've seen 4"x4" 1/8" steel as a requirement for the belts, but that seems excessive for the sub straps since they don't have to bear the weight of the driver.
Aug 8, 2005, 11:00 AM
#6
Yeah, they don't, but they do experience extreme sudden loading during an impact. For a safe mouth of 2 sub straps (aka a 6-point), 4 inches is the width of the two belts, and the 1/8" steel is perfect. It seems exxcessive, but sled teting these into walls at 40 created insane load. Watching it in slow motion was actually quite eye-opening...
Trending Topics
Jan 30, 2008, 08:18 PM
#9
Evolving Member
iTrader: (1)
Join Date: Sep 2006
Location: Nebraksa
Posts: 170
Likes: 0
Received 0 Likes
on
0 Posts
People,
I used to work for Schroth USA, the company that imports, assembles, and sells every Schroth belt and hardware in the country. In no way is the sub straps safely mounted based on this install. Without getting into too much technical detail, the angle of the sub straps (the "Crotch straps") as the come off of the cam lock must be at least 45 degrees, which is close to pushing it, moreso should be 60 degress from the vertical plane. In order to accomplish this, you MUST HAVE the factory seat modified with a substrap hole to route the belts through. You may say, well, other than this, its OK, but this part is super critical. You are safer actually wearing the stock 3-point seatbelt than wearing a 6-point harness installed like this. Contact joe@hmsmotorsport.com for any additional questions. He has sold, installed, and adjusted belts for 15 NASCAR drivers, including Jeff Gordon, Mark Martin, etc., and he is known to nearly all NASCAR crew chiefs, as well as the director of safety. PM me if you need more answers.
Vtluu, this is in no way flaming you whatsoever. The other steps are well written and documented, and the bracket folding is perfect. About 90% of professional racers mount sub straps wrong, unsafely, and the education is just not there.
I used to work for Schroth USA, the company that imports, assembles, and sells every Schroth belt and hardware in the country. In no way is the sub straps safely mounted based on this install. Without getting into too much technical detail, the angle of the sub straps (the "Crotch straps") as the come off of the cam lock must be at least 45 degrees, which is close to pushing it, moreso should be 60 degress from the vertical plane. In order to accomplish this, you MUST HAVE the factory seat modified with a substrap hole to route the belts through. You may say, well, other than this, its OK, but this part is super critical. You are safer actually wearing the stock 3-point seatbelt than wearing a 6-point harness installed like this. Contact joe@hmsmotorsport.com for any additional questions. He has sold, installed, and adjusted belts for 15 NASCAR drivers, including Jeff Gordon, Mark Martin, etc., and he is known to nearly all NASCAR crew chiefs, as well as the director of safety. PM me if you need more answers.
Vtluu, this is in no way flaming you whatsoever. The other steps are well written and documented, and the bracket folding is perfect. About 90% of professional racers mount sub straps wrong, unsafely, and the education is just not there.
Last edited by dragmod; Jan 31, 2008 at 08:16 AM.
