Question for harnesses in 993 re: safety of using lapbelt mounting points
#16
Three Wheelin'
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Derek helped w my install. Hes a great guy and very willing to spend time on the phone or in person discussing your needs. For my sub belts I welded a piece of 1x2 steel tubing to the seat adapter plate amd wrapped the sub belts around that.
#17
Race Car
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Someone correct me on my logic here.
If the seat mount is strong enoughg for the 3 point belt, why wouldn't it be strong enough for the 6 point? Doesn't spreading the load over more attachment points lower the load on any one point? Example, if my 210 lbs is displaced forward in an accident, with the three point the seat mount would be taking a third of the load. A 6 point would spread that load over the shoulder mount points, and the sub mount points resulting in less load on the seat mount.
What am I missing?
If the seat mount is strong enoughg for the 3 point belt, why wouldn't it be strong enough for the 6 point? Doesn't spreading the load over more attachment points lower the load on any one point? Example, if my 210 lbs is displaced forward in an accident, with the three point the seat mount would be taking a third of the load. A 6 point would spread that load over the shoulder mount points, and the sub mount points resulting in less load on the seat mount.
What am I missing?
#18
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Someone correct me on my logic here.
If the seat mount is strong enoughg for the 3 point belt, why wouldn't it be strong enough for the 6 point? Doesn't spreading the load over more attachment points lower the load on any one point? Example, if my 210 lbs is displaced forward in an accident, with the three point the seat mount would be taking a third of the load. A 6 point would spread that load over the shoulder mount points, and the sub mount points resulting in less load on the seat mount.
What am I missing?
If the seat mount is strong enoughg for the 3 point belt, why wouldn't it be strong enough for the 6 point? Doesn't spreading the load over more attachment points lower the load on any one point? Example, if my 210 lbs is displaced forward in an accident, with the three point the seat mount would be taking a third of the load. A 6 point would spread that load over the shoulder mount points, and the sub mount points resulting in less load on the seat mount.
What am I missing?
Schroth makes the GT3 seat specific harness for Porsche
Recaro makes the PP/RS and GT3 seats for Porsche, and now the new GT2 seats with similar seat belt/harness mounts
http://www.suncoastparts.com/product/GT2Seats.html
Assuming per Porsche specs
Assuming seat mount points in a Porsche chassis is designed to be a strong mounting point for seats, with the reduced weight of the GT3 seats, and addition of harnesses, I don't understand where the added stress is coming from for DE (but race cars probably needs to adhere to racing assoc regulations regarding where to mount harnesses, which why what Bill V posted makes sense)
And not all owners want to drill mounting points into there street Porsches, hence an entire industry exists for that (ie: Brey Krause, Das Sport, Tequipment, Etc)
I can only assume since Schroth didn't have any part of designing the chassis in where their harnesses will be mounted, a better safe then sorry advise seems understandable
#19
Rennlist Member
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I asked those questions too and he had reasonable answers. on a 3 point most of the load is actually the pillar and sill points. ON a 6 point I assumed most would be shoulder in a forward crash - but he said actually the biggest load is still the lap points with something like 30 and 15% the shoulder and sub belts (I may be off by a few, but same point). And speeds are much higher compared to what they test the seat anchors in a crash for DOT or similar.
Also he did mention the floor pans in the 996 and later were very different and were actually tested so not a concern there. He admitted there is no testing on the 993/964 pans to even no - but looking at its design he surmised it wasn't great - probably why the post by BillV suggested reenforcement for RS standards.
I think its a balance. Mostly they want me/us to know its a compromise in the ideal safety design environment and don't be thinking we are getting all the protection these are intended for. THat is legally necessary and a good philosophy. Similar to using harness or fixed seats without roll bar I am sure. Or airbag in an environment that now defeats the 3 point set up. I don't know how BK doesn't at least mention this situation though.
Also he did mention the floor pans in the 996 and later were very different and were actually tested so not a concern there. He admitted there is no testing on the 993/964 pans to even no - but looking at its design he surmised it wasn't great - probably why the post by BillV suggested reenforcement for RS standards.
I think its a balance. Mostly they want me/us to know its a compromise in the ideal safety design environment and don't be thinking we are getting all the protection these are intended for. THat is legally necessary and a good philosophy. Similar to using harness or fixed seats without roll bar I am sure. Or airbag in an environment that now defeats the 3 point set up. I don't know how BK doesn't at least mention this situation though.
#20
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Hi clib,
I have a 996 gt3 seat ready to install on the driver's side of my '97 c2s. I wonder if you could share what seat brackets and sliders you used? I've done a fair amount of research but haven't found anything conclusive for this combination.
Still thinking through a harness solution, will be talking to the engineers about a floor installation following Bill's post (many thanks as ever bill).
M.
I have a 996 gt3 seat ready to install on the driver's side of my '97 c2s. I wonder if you could share what seat brackets and sliders you used? I've done a fair amount of research but haven't found anything conclusive for this combination.
Still thinking through a harness solution, will be talking to the engineers about a floor installation following Bill's post (many thanks as ever bill).
M.
#22
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Hi clib,
I have a 996 gt3 seat ready to install on the driver's side of my '97 c2s. I wonder if you could share what seat brackets and sliders you used? I've done a fair amount of research but haven't found anything conclusive for this combination.
Still thinking through a harness solution, will be talking to the engineers about a floor installation following Bill's post (many thanks as ever bill).
M.
I have a 996 gt3 seat ready to install on the driver's side of my '97 c2s. I wonder if you could share what seat brackets and sliders you used? I've done a fair amount of research but haven't found anything conclusive for this combination.
Still thinking through a harness solution, will be talking to the engineers about a floor installation following Bill's post (many thanks as ever bill).
M.
Or you can purchase mounts from Brey-Krause
http://www.bkauto.com/category_s/224.htm
As e9stibi says, search it, there are a few threads on GT3 seat installs
#23
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Here we go:
https://rennlist.com/forums/993-foru...n-summary.html
If you follow this by the letter, you will get a great result. I learned when I prepared for the job, that seats can be tough if you do not follow other people's experience. I summarized mine and other RL's learnings in the posting:
https://rennlist.com/forums/993-foru...n-summary.html
If you follow this by the letter, you will get a great result. I learned when I prepared for the job, that seats can be tough if you do not follow other people's experience. I summarized mine and other RL's learnings in the posting:
#24
Rennlist Member
Thread Starter
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as e9stibi and IamSMC said above - lots of options. As also said, follow one method that has been done already. I actually got my seats from IamSMC. See first if what you receive already has the 996 sliders on the seat - if so, find one of the threads that tells you how to modify them and then they go right in pretty easily. Sounds like you may just have the seat shell - if so you need to get the brackets and some sliders. Then you need to follow a thread like the link above or BreyKrause also sells a kit to mount directly to the floor which is particularly useful if you are very tall however, it must be a pain to use on a street car as you loose any fore/aft adjustability.
#25
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Thanks Guys, I appreciate the help. Couple of clarifications:
1. You are correct, I only have the shell
2. The person I bought it off used BK side-mounts and Sparco sliders but unfortunately I don't have the part numbers. Am pretty sure that BK 9078 is correct given the car is RHD.
I have been collecting together prices and availability today and am trying to decide between the OEM route and the one in e9stibi's thread. That thread is by far the best solution that I have found during my research especially in conjunction with Bill's recaro PP info. I had come across them before (don't want you to think I hadn't bothered searching) but I had lost a little confidence after seeing all the permutations in other places. I'm obviously keen to get a safe set-up; its good to hear form those who have had success.
clib - can I clarify that in going OEM is there anything other than the side-mounts and seat-rails required to run the original 3 point belt? I have had some large differences in the quotes for OEM equipment as some seem to include various fixtures for the belts etc.
Am awaiting more info on Monday when technicians are about.
Thanks again,
M.
1. You are correct, I only have the shell
2. The person I bought it off used BK side-mounts and Sparco sliders but unfortunately I don't have the part numbers. Am pretty sure that BK 9078 is correct given the car is RHD.
I have been collecting together prices and availability today and am trying to decide between the OEM route and the one in e9stibi's thread. That thread is by far the best solution that I have found during my research especially in conjunction with Bill's recaro PP info. I had come across them before (don't want you to think I hadn't bothered searching) but I had lost a little confidence after seeing all the permutations in other places. I'm obviously keen to get a safe set-up; its good to hear form those who have had success.
clib - can I clarify that in going OEM is there anything other than the side-mounts and seat-rails required to run the original 3 point belt? I have had some large differences in the quotes for OEM equipment as some seem to include various fixtures for the belts etc.
Am awaiting more info on Monday when technicians are about.
Thanks again,
M.
#26
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can I clarify that in going OEM is there anything other than the side-mounts and seat-rails required to run the original 3 point belt? I have had some large differences in the quotes for OEM equipment as some seem to include various fixtures for the belts etc.
Am awaiting more info on Monday when technicians are about.
Thanks again,
M.
Am awaiting more info on Monday when technicians are about.
Thanks again,
M.
That's the inboard side of where & how the OEM female receptacle is attached for 3 point belts on the OEM sliders
#30
Rennlist Member
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Bringing this thread back to life, as i will be installing track (DE) seats w/6 pts.
I bought the Rennline hooks for the outboard (door) attachments, will use the eye hooks/backing plates that Schroth supplies for the sub belts (drilling required). That leaves the tunnel mounts. Here is my question:
Is the most secure attachment to drill the tunnel & use the eye hook/backing plate arrangement ? Is there room inside the tunnel for a backing plate ?
I bought the Rennline hooks for the outboard (door) attachments, will use the eye hooks/backing plates that Schroth supplies for the sub belts (drilling required). That leaves the tunnel mounts. Here is my question:
Is the most secure attachment to drill the tunnel & use the eye hook/backing plate arrangement ? Is there room inside the tunnel for a backing plate ?