I've got a Hard Dog Street Cage with UltraShield SM seats. When the seat is lined up with the steering wheel, the shoulder harness holes are off-center with respect to the cage's seat-back bar. This is what it looks like:


So, what do you guys think? Is this acceptable? Or should I add a separate harness bar? Only the driver's side has this issue, passenger's side is fine. I'm leaning towards adding a separate harness bar.

 

I'd feel safe with it. Really my only bug would be my OCD. The bigger danger might be the sharper edge of the seat though.

Hard Dog's bolt in bar will give you another few inches, as it goes to the seat belt tower. Later down the line you could trade with someone who doesn't have a harness bar for $50 cash or something.

Seat mount pics for anyone who cares:

https://www.miataturbo.net/build-thr...d-76869/page6/

 

Thanks Josh. The other issue is that it will let me get my seat-back brace better centered on the seat.

 

It should be fine. I'd actually be worried about the clamps chafing it. The seat openings are rounded off and smooth on those ultrashields on purpose.

 

I'd probably replace the exhaust clamps with aluminum shaft collars. Those have all chamfered edges and should be lighter. I dont think I've seen a miata with a bolt in roll bar that didnt have this issue. The seat WILL twist if you wreck it though.

 

The exhaust clamps are surprisingly smooth. Similar to the IO Port clamps. Was planning to use the clamps to fab a seatback brace (which I would like to get centered on the seat -- another reason this is bugging me). If I add a separate harness bar, I can also separate the harnesses from the brace to avoid any possibility of chafing.

Got a source for AL shaft collars?

 

mcmaster

 

Not an issue in mine, but that's because the NBs don't have a harness bar in the HD (due to glass rear window interference) and so HD sells a bolt-in harness bar instead.



--Ian

 

Looks like you dont have the harness webbing properly threaded thru. Maybe it is just the camera angle.
Click & See Page 25//

 

IT's routed per the Schroth instructions (the link you posted, although for some reason following it from the forum doesn't work). The loose end is routed down behind the seat, which is probably why it looks wrong.

Tony at TC Design installed them, so I would've been very surprised if it was wrong.

--Ian

 

A friend of mine who's a longtime racer suggested that I could fold the shoulder harness webbing to get it centered on the seat better. He mentioned that it is common for race harnesses to get folded to fit 3" webbing into 2" fittings. I mocked up the fold. Looks like this. I dunno?


Also, the AL shaft collars Leafy mentioned are $12 from McMaster-Carr. They look slick. Going to get some.

Thanks for the ideas all.