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996.1 cab C2 manual

Should be fine but that's the most you'd want the wheel sitting out in the arch, especially with no aerokit to even the look out a bit.

Standard Mk2 GT3 are 11 inch with 65 offset. Yours are gonna sit 9mm further out but if your using 285 tyres instead of the 'correct" 295 you'll save 5mm in and 5mm out so you'll be 4mm further out than factory GT3.

I'm sure my tyres don't run within 4mm of my arch lips so there should be room.
Again though I'd just worry about the wheels looking to wide for the car if they're gonna stick out. Should be ok though.

Edit. Just been out to the garage and I wouldn't want the front lips of my wheels sticking out another 9mm. They may not catch but I think it's just too far out to look right. :nooo:
Oh and if you did move upto 295s then it really would be close, clearance wise.

Henry will know though. :thumb:
 
Those will be pretty much flush with the arch but with 285's I think you will be fine.
Ive run 10in et38 on mine which stick a further 5mm out and they didn't rub at all however that was with 265/40 in tyres so slight stretch.
 
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Chris from CG recommended using a harness for track days as I've got a Recaro SPG seat which is designed for a harness.

However- I have no idea how I'd mount the shoulder straps, and fitting an actual harness bar seems somewhat over the top:

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The problem you have is getting the harness angle correct as it passes over your shoulders. Mounting the harnesses to the rear seat-belt anchor points is easy, and is what many people do, but that creates a very acute angle over your shoulders and transmits loads down through your spine, which is a no no, so you need something to create the correct angle.
There are basically three options.
1.)Harness guide bar - the harness mounts to the rear seat belt anchor points but passes over the bar which creates the proper angle over the shoulders. These are pretty quick and easy to install / remove, though I'm not sure I've seen one fitted to a 996 cab as they tend to attach to the B-pillar upper seat belt mounting point.
2.)Harness truss - this is rather more substantial with a greater number of anchor points. The harness mounts direct to the truss. This sort of thing.....
https://www.bkauto.com/R_1035_Harness_Mount_Truss_p/R_1029_p/r-1029.htm
3.)Full roll-cage - harness mounts to cage, but this is probably overkill in this scenario.
A less invasive solution may be to fit eyebolts into the rear bulkhead, though I have no idea how strong a mounting point that is in a 996. It was generally deemed acceptable in a 964. Hopefully someone else might be able to advise on this......... ?

Jamie
 
Harness - I hear you on the angle aspect, I do wonder whether I'd be within the 20 degree range that's considered ok (and would pass scrutineering) as the lower seat belt mounts are really pretty high up when compared to my shoulder harness openings on the Recaro SPG. I may get a tube welded in behind the front seats and use it primarily to attach the upper edge of a luggage net, but secondarily as a harness bar, if I go ahead and delete the rear seats and turn that area into a luggage storage compartment.

In seat related news:

48886345793_c5d6b2f992_b.jpg


Just need to strip the paint, make the hole a little larger, wave the TIG at it and wallop. Plus a squirt of satin black rattle can.
 
If those are for fitting eyebolts for harness lap belts, the genuine 964 RS mount has the threaded boss already attached.
It's generally felt to be better to mount the belts direct to the chassis eg lower B-pillar seat-belt mounting point than to the seat rails. This tends to be difficult on the transmission tunnel side, so the 964 RS mount is a solution to that, allowing fitment of the seat belt receiver and an eyebolt for the harness lapbelt. The fact that the seat rail mounting bolts are made of cheese always made me nervous - I've seen the seat mount towers on the chassis crack as well. The solution is to drill the transmission tunnel and weld an eyebolt mounting plate on the inside of the tunnel.
I have no idea what the access is like to do that on a 996, but it was certainly a viable solution on the older cars.
 
I've got the 964 RS mount in the car at the moment - challenge with that is that it doesn't line up with the mounting bolts on the side-mounts/runners.

The two brackets pictured do, having been supplied with the seat mount, but they didn't have the 7/16th threading which the 964 RS mount does.

Essentially the bungs in the picture are direct copies of the inserts in the 964 RS mount, and will convert the brackets that came with the seat mount to BBI-racing/964-RS hybrids.

I'd then need to have a think about mounting harness lap belts, I'd probably screw an eyebolt into the mount and clip to that - I don't mind ten minutes of faff at the start and end of the track day.
 
Yes, taking harnesses in and out is not a big deal, though the tunnel side can be pretty fiddly - small hands / strong fingers required !

I'd also recommend fitting a GT3 sub-bar under the seat to attach sub straps. To my mind four point harnesses aren't great as you can slide under them in a frontal impact. Five point as a minimum for me.

(It's a bit of a pet peeve for me - you so rarely see harnesses fitted properly using the correct double strap-wrapping technique, and even if they are, they're seldom adjusted properly by the wearer, with the buckle usually somewhere around the navel !)
 
The BBI seat base I used has mounting points for either five or six point harnesses, so that's no problem. The only question is the shoulder straps.
 
Many thanks to Slippydiff for lending them and Mister Corn for moving them - these are now with BG Developments to have my new brakes designed.

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I'm interested to hear what size rotor these 18" LM's can hold.
 

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