Do Metal Miata hardtops exist? V2

If you'll allow me to approach this from a different angle- I used to rally an RX7, currently rally a BRZ, and have done an unhealthy amount of examination of whether an MR2 is viable so I ask; do you fit?  Safely?

I have a system for this: first, get a scrap piece of cage tubing and stick a short piece of sfi padding to it.  Sit in the car with your helmet on, and pass that between your head and the roof, the top of the door, and whatever else structural is nearby- that's your best case scenario for cage fitment, is there room?

If that passes, next find homes for 2 typical fire extinguishers, a 4L suppression system tank, 3 road triangles, a few notebooks, a tow rope, and a first aid kit, all inside the cage with you- you can even use cardboard to block these out if you want to visualize it.  Now get a friend, and both of your helmets, put the helmets somewhere in the interior with you and all that stuff you already packed, add a couple water bottles for good measure, and go for a drive.  This will be what the space is like on transits, for hours every rally weekend- still big enough?

I point this out because it's a line I'm used to trying to draw for myself. A miata would be cool, but for me at least it's probably not big enough for all the stuff that comes with rallying.

In reply to ¯\_(ツ)_/¯ :

I'm 6'2" and I think I could just make it work, though I'd have to wear my helmet during transits.  Which is probably the safe thing to do anyway in a caged car.  At least for the interior stuff, but I'm not sure what I'd do about a spare wheel/tire--there's no way you're getting a rally sized wheel/tire combo in the trunk.  Especially not after mounting the fire suppression tank there which I think would be the only option.  (Though, note, you don't actually need a 4L bottle.  An SFI 17.1 5lb gas bottle is a heck of a lot of smaller than that and ARA legal.)

We were able to fit the fire extinguishers (in front of seats), road triangles (same), notebooks (net attached to the transmission tunnel), tow rope (trunk) and first aid kit (attached under dash with velcro straps) inside an NA Miata. Water bottles were handled with Camelbak "Unbottles" on the rear deck and the hoses attached to the harnesses so we could easily drink at any time. No suppression system because that wasn't required by the rules, but the bottle could have gone on the rear deck behind the seats. I also had a 225/45-15 tire on a 15x8 wheel in the trunk. Took a little hammer forming, but it fit.

For short transits, we'd put the helmets in the passenger footwell. Yes, it was crowded. For longer ones, we put them in the trunk. I honestly don't recall where we kept the transit headsets when we were on a closed stage.

In reply to Berck :

For the spare- early Miatas can still fit 13s right?  To me half the appeal of running something that small is the ability to get away with a lighter wheel/tire combo.

In reply to ¯\_(ツ)_/¯ :

You can fit 13s on an NA miata, but are there any gravel tires?  I found a bunch of near-free 14" rally wheels for the BMW, but the 14" gravel tire choices in the US seemed non-existent.  Looked like there were options if I wanted to pay for shipping from the UK.  Also, given the stupid weight of gravel tires, I'm not sure that a smaller wheel actually saves you weight?

You can fit a 185/60R14 spare in a Miata trunk barely.  Keith did get eventually get something like a 225/45 in the trunk... but with no hinges or latch and some non-pictured hammering.  You're obviously going to want something much skinnier/taller for gravel.

Not sure that there'd be room for a fire bottle on the rear deck with an FIA cage.  Maybe.

Looking through the rules, though, I'm not sure there's anything that says you can't just mount the spare on top of the trunk?

If it were legal, I'd absolutely be trying to make it work.

In reply to Keith Tanner :

If you put the helmets in the trunk does that mean you didn't end up carrying a spare?

In reply to Berck :

Tons of 13s- Hoosier and Pirelli make them, or MRF if you're feeling cheap.  Thank the guys running old historic stuff in Europe.

I had both the spare and the helmets in the trunk. They had to go in just the right way if memory serves, and it helped that the spare was mounted offset in the trunk so there was space beside it. No way I would have run without a spare. The hinges weren't a factor in the spare installation IIRC, the hammering was mostly on the aft wall of the trunk off to one side. This pic of the 205/50-15 (same diameter, not as wide) shows the latch mount is untouched (bottom right corner of the pic).  I removed the hinges and latch for weight savings and I've been cursing myself ever since :)

If you try to go any taller than 23" tires, you're going to run into a bunch of other problems with clearance that may require you to handicap the car's suspension travel. So I'd recommend sticking pretty close to that diameter. Skinnier would make life easier.

Here's the rear deck with the Unbottles mounted. A 4l bottle is only 6" in diameter and 14" long, you could fit it back there. That cage met the FIA specs for 2011, IIRC, now it would require another diagonal in the main bar but that wouldn't affect the deck.

Suppression bottle has to be inside the structure of the cage, although if you sent the supports further rearward I see how you might be able to get it there.

The Unbottles can go in other places, so you could potentially put the bottle laterally at the front of the rear deck. At 6" in diameter, I'll bet I could get it under the dash if the heater core was removed. Let's just say that mounting the 4L bottle is not the biggest obstacle you'd have to deal with in making a rally Miata. The convertible aspect is liable to be more of one.

Thinking about it, though - even if the coupes are expensive rarities, they're still going to cost you less than a new WRX. So maybe that idea isn't so crazy. It'll be another 5 years before they're legal to import into the US, though - better buy one and stash it in Canada before the US causes the prices to spike.

In reply to ¯\_(ツ)_/¯ :

Is this one of the rules tech inspectors are making up?  I don't see anything about the suppression bottle needing to be inside the cage:

2.3.5 Fire extinguishers a) All competition vehicles must be equipped with all of the following: i) An “on-board” system that uses either manual or automatic activation. 1) All bottles will be secured using a metal strap and have a fill gauge that is visible for Scrutineering. Activation point for the fire system must be located within easy reach of the driver and co-driver when seated. 2) All such systems will be installed and serviced in accordance with the manufacturer’s instructions. Installed system must meet one of the following standards: • SFI Spec 17.1 and display a manufacturer appearing on the current respective list of SFI Spec 17.1 manufacturers at sfifoundation.com • FIA 8865-2015 • Currently listed as homologated for Rally on Technical List n° 16 of the FIA website (fia.com) 3) The fire system cylinder shall be securely fastened, in such a manner that it can be checked during a technical inspection and may be removed periodically for weighing. 4) All on-board systems shall be identified with 2 circle “E” decals one at the release location and the second on the outside bodywork in line with or as near to the release location as possible.

In reply to Berck :

It's the "All such systems will be installed and serviced in accordance with the manufacturer’s instructions" part.  I'm yet to encounter one that says you can install it outside the cage.

In reply to ¯\_(ツ)_/¯ :

Here's the installation instructions for mine.  I don't see anything that precludes mounting it in the trunk.  I've got it behind the codriver's seat right now, but I was thinking about moving it.... 

In reply to Berck :

Very interesting, gonna keep that one in the back pocket for people with weird small cars then.  Most use the Lifeline systems which want to be in the cage with you.  Thanks!

In reply to Keith Tanner :

It might still be possible, but the Miata coupes only came with a fiberglass top instead of a metal one. You might end up running into the same issue, but at least then you'd fall into the closed-body classification.

In reply to L0b56 :

Yeah, the way I read the rules you'd still need to comply with:

"Sunroofs and/or roof panels of any other material must be replaced with metal of equivalent strength of the roof panel and must be fixed in the closed position by welding or steel fasteners."

But I think you actually could comply with that if you started with a coupe.  I'm curious if that's actually the intent of the rule, though.  It seems like there's any number of fiberglass cars this would suck for?

L0b56 said:

In reply to Keith Tanner :

It might still be possible, but the Miata coupes only came with a fiberglass top instead of a metal one. You might end up running into the same issue, but at least then you'd fall into the closed-body classification.

The production 2003-04 Miata coupes had a steel roof. The one-off 1996 show car was fiberglass - and Mazda won't let that one out of the museum anyhow :) 

There was a factory metal-topped coupe version of a Miata available in the US. I mean, sure, it was a lengthened platform (or more accurately the Miata was a shortened platform) and it had some funny looking pistons, but it was basically a Miata. 

Unfortunately I doubt this is of any help for this situation, although nocones did post a free RX-8 on Facebook this morning. 

Looks like there are at least two rally RX8s. One runs a 20B for a 50% increase in the likelihood of apex seal failures :)

An RX-8 (maybe with an MZR swap for reliability) starts to sound like a pretty reasonable idea.

Here is another idea, not sure if it has been brought up or not: How hard would it be to bond some sheetmetal to the fiberglass top, cut it to fit, and weld that to the car at the windshield and the quarter panels, and the behind-the-trunk-panel-thing? May also want to weld in the frankenstein bolts to keep the safety folks happy at that point. 

jharry3 said:

"Rules are for the obedience of fools and the interpretations of smart men."  Colin Chapman

After reading the rule text it seems to address the different issue of removable roof panels.   Nothing about removable hardtops, which are not panels like on a Targa style roof, or sliding style sunroofs.    

 

The rules text also basically says they reserve the right to not allow your car, period.

They don't have to let you enter, it's a private club.  There's no Fastest Indian "if we show up they have to let us run".

Berck said:

An RX-8 (maybe with an MZR swap for reliability) starts to sound like a pretty reasonable idea.

Our own NONACK (¯\_(ツ)_/¯) found that a major limitation for an RX8 in rallying is the stubby T-rex arms on the rear suspension that don't handle large amounts of travel well.

In reply to Pete. (l33t FS) :

Exactly.  And they really don't seem motivated to increase participation.  My 2 experiences thus far with ARA tech is that they let me run, but they manage to come up with a list of grievances that are nowhere to be found in the rules.  The best is probably the tech volunteer who told me, "I feel sorry for you because your car is so crappy."  And he hadn't even seen how slowly I was going to drive it!

In reply to Berck :

I am sure that they were happy to see you driving slowly, and not yeet it into a ditch on the second corner of the first stage.