perelet

Can you guys please tell me where was "stock" shoulder harness mounting point(s) on Clubsport models equipped with Heigo Roll bar?

Question is about original factory historically correct setup, not modern DE or clubracing rules, or gazillion of other ways to bolt harness.

According to Cupcar's post in this thread there's single eyebolt that is using read passenger seat belt mount:


On other side I've seen 2 eye bolt setups, but some of them seem to be modified cars

This car does look modified ( see wing) or is this 993 rs?:


Also this one got wing, and eye bolts are in different location not sure if this is factory car or again is this 993 rs?:



This has Sabelt harness instead of Schroth, plus roll bar is aluminum also not sure if it is factory ...:


Thanks!
Oleg.

freedman

Yellow car is a 964 (see the rear quarter window seal)

Unfortunately thats the only thing I can deduce from the pics

kos11-12

I think there is a bar going across the shoulders with 2 guides per seats, this is where they should be fitted,

I think I have seen on the ACU book that for safety the belts should to be short and fairly in line with the seat holes...

tat

I believe all the NGT "Clubsport" variants had a welded-in cage (made by Matter?) that included a harness bar, around which the shoulder straps were wrapped.

As far as I know, no 964RS variants were built with mounting points specifically for harnesses. But they may have retained the mounting holes for rear seat belts, and child seats - these look to be what is being used in the first two pictures in the opening post.

The Heigo cages pictured are after market bolt-in half-cages. Neither of them include the optional harness bar, which goes across the width of the car between the vertical hoop. I don't think Heigo cages were ever a factory option on any Porsche.

RSGulp

The white 964RS at the bottom is mine. It has the factory (I believe) mounting point next to the C pillar, and has an additional mounting point (installed before my ownership) on each side toward the centre of the car. Many 964RSs I've seen here in Europe have the same mounts. 964RS N/GT Clubsports I've seen here in Europe have exactly the same mounts.

If you like I can take measurements to help you out. I might be able to obtain some pics of the N/GT Clubsport mounts (without carpet) which might help.

perelet

RSGulp, thanks for confirmation! And if you can please measure and post pic of 2nd mount without carpet (I presume it is standard FIA backing plate) it will be great!

That explains why no extra shoulder harness mounts are mentioned on well known diagram (below). So we are inline with Cupcar's post - single eyebolt from factory and later almost everybody added 2nd mount.




Thanks!
Oleg.

RSGulp

Hi Perelet,

I saw a friend this weekend and took some photos of his original, factory built 964 Cup Car.

The cars came from the factory with the original C-pillar mount (as per Carrera 2 shell) and an additional 'middle mount' which is where BOTH shoulder harnesses were originally secured.

The single mounting later didn't meet updated FIA regs, so Cup Cars used the original C-pillar mount and had an additional inner mount installed. This is the set-up my 964RS has and also most (if not all) of the other RS and N/GT Clubsports I've seen here in Europe. I haven't lifted my carpets so I don't know if 964RSs also came with the 'middle mount'.

As was mentioned above, drivers now often choose to secure their harnesses to the cross-bar of the welded-in cage. This allows for shorter harnesses overall and therefore lessens the possibility of the belts stretching in the event of a crash.

I'll attach the pics below. Unfortunately I didn't have time to take measurements as he was racing, but he will take a measurement from the C-pillar mount to the inner mount. I've also asked for a photo taken from the engine compartment of the underside of the added mount which might help you with installation.

Hope this all helps.

RSGulp

Okay, the C-pillar and inner mount are 295mm between centres. It's not possible to photograph the mount from below as it's not visible and inside a void. He assumes its drilled through into solid structure and tapped from above.

RSGulp

Perelet? You still here?

perelet

RSGulp, thanks a lot!

It is interesting observation that 2nd hole is probably tapped and no back plate is used, yes there's double layer of sheet metal in that place.

Did anybody seen factory documentation on this FIA compliance update?



Oleg.

RSGulp

Hi Perelet,

I took one of my inner mounts out today. It is definitely threaded into think steel inside the hole and goes around 8mm deep. I put a thin screwdriver inside the hole and it stops when it hits the bottom. I imagine there is a solid bar between the two skins. Or possibly a plate is somehow fed in through one of the larger holes towards the centre of the car?

Unfortunately I couldn't take any pics as the hole in the carpet (in my RS lwt) is very small and you just can't see anything clearly. When I next see an NGT or Cup I'll investigate further for you.

Rich

perelet

Rich, I looked at regular 964. As I can tell there are 2 separate threaded backing plates (about 8mm thick) spot welded welded under C pillar and center 'Factory' mounts.

Interesting fact 'Factory' mont is thread is M8x1.25 which is smaller than C pillar hole which is standard M11x1.25.

Metal thickness at 4mm accessory hole is about 3mm on regular 964 and that is where eye bolts are going on your pics. I'm curious is RS had backing plate welded there ... which will be only possible before chassis is assembled ... (no published source confirms that).




Here are backing plates on your pics:



If you get a chance can you please look at hole for inner harness eye bolt - is there backing plate under it?


Oleg

Strega(UK)

I went through all this a year back and decided I did not like the odd offset of using the factory holes but did like the factory strength and the fact I did not have to permanently modify my car, so I fabricated a 1/4 steel bar to pick up on the original holes using small spacers then welded anchor plates underneath the bar in the locations I wanted. It all looks factory and can be removed if needed.

HiWind

wow super detail and pics - worth a bump for any pics of how these plates look inside the engine bay? Or are they inside the firewall /back shelf?

BeReal

Interesting is right.

If anyone has any more info on these feel free to post!