As long as we're going there:

https://www.miataturbo.net/attachmen...ine=1317860039

Im also doing a winter cage. My main concern is side penetration since Im planning on doing W2W racing at some point in the near future.

looks like a chassis for drag racing.

Bob

Yea, drag car project.

That is very much like what I am talking about. I have my donor chassis now. It is basically trash from the front sub frame attachment forward but I didn’t plan on using any of that part anyway. Also now looking at all the metal that I will be removing from other places in the unibody.

Bob

What I do like about the carbon fiber time attack car main roll hoop is that it is pushed out wider in the chassis and integrated into the structure of the aft door B-post. Note there is no seat belt tower like in a Spec Miata or IT ruled cage.

I intend for most of the unibody structure to be gone in that area and I want the roll bar out there so it can replace the missing structure with some more ties to the chassis. I’m looking at removing significant portions of inner structure like the two inner walls of material behind the rear quarter panels along with the rear inner fenders and a bunch of the other stuff with about the only thing left of the stock anybody is the two box section rails that the sub-frame mounts too. Everything else that is not external shell will be removed or replaced with something lighter or more purpose fictional. I plan to go a bit further than many others have gone that I have seen pictures for but not quite a full tube chassis. Allot of the using the cage to re-engineer the chassis structure stuff is not allowed in spec miata or IT rules but in the GT rules and Solo Prepared rules it is I want to take advantage of everything I can.

The one chassis with the re done front end looks cool but It looks to me like those tubes would be much thicker and potentially heavier than stock. I think it is more than necessary. I think I would make it lighter but still very similar. I’m starting with a chassis that hit a telephone pole and everything in front of the front sub frame attachment is wadded up garbage anyway. In the end I still think I might end up front heavy with all the weight reduction I’m planning so I am also looking at shifting the engine back. Looking at the rules I think I can do that. The rules say I can’t modify the firewall for head or cylinder block clearance but I can for the cam angle sensor electrical cooling or the bell housing. Might be able to move the engine back 4 “ I’m guessing.

Bob

http://www.customcages.co.uk/Rollcag...ype=Multipoint

I don't understand the door bars in this design. I can only presume that no bar was located where the seat base would sit because.... well... that's where the customer's seat base sits. I can't argue with the rest of it though - not least because it's been designed by a reputable firm and is all FIA and MSA approved, so frankly it must be pretty sound.

This is interesting... what is it?
Is it Miata subframe based?

is there a build thread somewhere?

I think there might be some issues with SCCA rules with that But I think FIA approval will supersede. The big issue I see is for a LHD car that design would make use of the dead pedal impossible with where the bar attaches down in the foot box area.

Bob

Did they deliberately design the door bars that way to make the car a huge, huge bitch to get in and out of?

Looks more like they forgot that people have to actually get in and out of it. :giggle:

I think you're all just bitter that you're not as young and nimble as you once were :giggle:

But serimeowsly, I think the door bars have been designed for someone who wanted X bars (note the non-stripped doors) but who couldn't locate the lower bar by the seat because of packaging constraints. All seems a bit compromised to me, but equally, I don't know how else they could have done it given the space.
Also, you all need to get in and out of Caterham or Elise road cars a few times. Then sit back and have a think about why you're moaning about ingress and egress in a flippin' race car!

Pfft, a caged Caterham is something to manage at 6'3" ... :D (trough the top circular braces is easiest).

I sadly only have this old (2005) picture of my AMP-cage (bolt in, that's why the front part is not further forward.
https://www.miataturbo.net/attachmen...1&d=1318275677
It's also tight toward the wheel, that's why I use a 300mm (a bit too small), not in this picture, I was just happy to get it together back then.
The seatbelt towers are removed to get the cage in (but can be bolted back with the cage in place... Not the safest option though...). The rear supports (going all the way back to the rear part of the subframe mounting point) are separation points.

The driver area is ok for me at 6'3" with 34" inseam (the bulb on the cage is needed), but the passenger side is useless with the roof diagonal.
Better seatbelt attachment would be a plus (HNRS is hard to get working now).
And having a complete cage all the way to the front shock towers is a dream (the front of the cars have a life of its own now), but I need to take the cage out for inspections... We all have our demons...

https://www.miataturbo.net/attachmen...ine=1318276878
:D

Sounds interesting Bob. Sorry if I missed it, but will this be an open-top car or will you run a hard top? If you are planning on a hardtop, is an Autokonexion fastback an option?

I have an AK fastback on my car, which I installed years after the cage was built. That cage was built to fit under an OEM hardtop. If/when I build my next car, it will also have an AK fastback, and I'll build the cage around it. There is a good bit more that can be done under the AK fastback, and the placement of the back glass is quite different.

I haven’t decided on a fast back yet. but I think this picture is good for showing a big chunk of stock metal bits that I intend to be gone along with trunk floor etc. car will mostly just retain the outer skin. The inner fender and two inner layers of quarter panel will be gone. Depending on what I decide on for wide body kit to fit 23.5X11 R16 slicks much of the outer fender is likely to be gone as well.

https://www.miataturbo.net/attachmen...1&d=1318279370
Bob

Care to elaborate a little? I'm waiting for my AK FB to arrive before I take my car to the cage builder. They have done plenty of SM cages, but I'm wondering what can they do differently under the fastback.

thanks!

Specifically?

https://www.miataturbo.net/attachmen...ine=1318289853

Cages built without thought towards rapid egress in the case of a fire are cages built without thought.

Impacts do not scare me. I have a containment seat, low NASCAR bars, and a HANS device. Fire, on the other hand, scares the shit out of me, and I have a 6-nozzle AFFF system.