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The Breakup (Miata build)

Posted: Tue May 06, 2014 8:54 pm
by drummingpariah
We're breaking up. It's not you, it's me. I suppose I always knew this day would come. I just want things you can't provide, and it's unfair to expect so much from you. I think we should split up. Take as long as you need to, I'm not kicking you out right now. I'll give you time to deal with it.

Yes, I've already moved on. I'm sorry, Yaris.
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I've always liked the Miata, but haven't ever lusted for one. I have no plans to make any major modifications to it, that's what the Datsun is for, but because the Datsun isn't finished yet and I absolutely loathe driving the Yaris, I picked this up to stand in for Ascutney I and take over daily driver duties. I believe I'll be in U6, unless I can get some decent wheels/tires before next weekend (unlikely, because I just blew a big chunk of my budget buying this).

I just tried looking through the rules for convertible-specific rules, but couldn't find anything. Could someone help me out, perhaps?

Re: The Breakup

Posted: Tue May 06, 2014 9:43 pm
by walterclark
From the technical regulations:

1. Roll bar required in all cars without a full steel roof. Roll bar should be equivalent in construction to cage specs

Re: The Breakup

Posted: Wed May 07, 2014 7:22 am
by drummingpariah
walterclark wrote:From the technical regulations:

1. Roll bar required in all cars without a full steel roof. Roll bar should be equivalent in construction to cage specs
Excellent. It has a roll bar of some sort, but ill have to see how old it is and what its made of.

Re: The Breakup

Posted: Wed May 07, 2014 12:26 pm
by drummingpariah
The current roll bar is just a single hoop with no rear bracing. I'll go snap a photo if that helps illustrate it. I'd like to replace it with a well braced bar (possibly a cage) eventually, but I'm not entirely clear on whether or not roll BARS need bracing or if it's just roll CAGES.
All Roll cages must have horizontal and vertical bars above, ahead, behind, and to the sides of the plane of the drivers’ helmet. Main hoop must be braced front and/or back, must have diagonal member(s) or equivalent within the hoop if spanning more that 3’.
The way that's worded, I can't tell if the last sentence is wrapping up the 'roll cage only' paragraph or if it applies to roll bar hoops as well.

Also, if I'm reading the helmet section correctly, I believe I can wear my CL16 motorcycle helmet and don't have to buy a new race helmet? It's DOT (meaningless) and Snell m2010 certified, which I think is acceptable?
http://www.revzilla.com/motorcycle/hjc- ... ic-helmets

*edit* Nope, after some more reading m2010 and sa2010 are completely different standards. Looks like I'm going to have to make room for another helmet on the helmet shelf.

*edit-x2*
Here's the lol-bar that I'm pretty sure I don't trust as far as I can throw the car:
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Re: The Breakup (Miata build)

Posted: Thu May 08, 2014 3:49 pm
by drummingpariah
A bunch of poring over the rules didn't really clarify what a roll bar is defined as, but after some reading about 'mousetrap bars' I'm not comfortable with what I have. I contacted the manufacturer and it's definitely DOM 1.75"OD .12"w tubing for the main hoop, and I contacted Dave Patten to see if he could point me in the right direction. It just so happens that the right direction is toward his shop, so I'm heading up there tonight to get some tubing. He only had 1.5"OD DOM, but upon looking through our 2014 rules/regs, I found that the main hoop I have is slightly overbuilt for our minimum specs:
Roll bar or roll cage must be of adequate construction, i.e.:
Mild steel DOM tubing, minimum diameter and wall thickness of:
1.25” x .120” or 1.38” x .090” under 1500 lbs.
1.38” x .120” or 1.50” x .090” under 2500 lbs.
1.50” x .120” or 1.75” x .090” over 2500 lbs.
Hopefully I'll have enough time to cut and tack some bracing together, then have a more experienced welder finish it up so it's good and sturdy.

I also took a good look at my tires last night, and was pretty disappointed. The fronts are relatively new, but are all-seasons. The rears are hardened, dry-rotted old things whose only claim to fame is that they hold more air inside than there is outside.
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Good-bye, any money I might have had for this week. You're going toward some decent tires along with mounting/balancing/alignment.

Re: The Breakup (Miata build)

Posted: Fri May 09, 2014 9:46 pm
by walterclark
Going with some braces is the right choice.

Our rules dont specify that bracing is required, but the fact is a free standing rollbar is likely to fold back or forward in anything but an ideal situation, leaving you exposed. If the car had a bolt-on hardtop then it would probably be OK unbraced.

Re: The Breakup (Miata build)

Posted: Sat May 10, 2014 7:50 am
by drummingpariah
I haven't been able to find a hardtop that would fit in my budget yet, I really want to ditch the soft top though. As long as I can come up with a bottle of inert gas, I'm adding bracing this weekend. I just don't trust this thing as it is. I just picked up all my new fluids so I've got my work cut out for me today.

Re: The Breakup (Miata build)

Posted: Mon May 12, 2014 12:11 pm
by drummingpariah
I spent some quality time under the car this weekend. I flushed the engine, trans, and diff oils and will check their levels again sometime this week to make sure nothing is low. I went through all the major suspension components with a torque wrench to try to identify the clunk I occasionally hear, but have nothing to report. It may just be the soft top bouncing around a bit, but I'm going to do a little more hunting before the event. New tires (Kumho XS) are en route, as is new driver's side mirror glass.

Roll bar bracing saw some heavy development last night. My friend Laurie came over, and we angle-ground a brace. It was so much grinding, then test-fitting, then grinding, then test-fitting, over and over and over for a few hours. She's taking it in to work to get proper measurements and make the corresponding second brace, along with some mounting plates for the bottom. Then we'll get together again, and she'll TIG it all together. This is just going to be rear braces, no diagonals yet (because of time constraints), but this is a lot safer than what the 'lol bar' was bringing to the table. Hopefully I'll have time to snag some photos tonight, to show what's actually being done. I definitely would have preferred to purchase a proper bar from Hard Dog, but it was slightly out of my time and financial budget for this race.

I ordered an FSA-2 helmet today, and I'm REALLY hoping it shows up by Thursday so I'll have it on Friday. http://www.saferacer.com/ doesn't specify where they typically ship from, so I'm a little nervous about it.

Re: The Breakup (Miata build)

Posted: Tue May 13, 2014 2:32 pm
by drummingpariah
The lol bar has evolved to a roll bar.
I still need to drill a couple fastener holes for the rear plates, but I feel much better about this bar now.
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I'd also like to clean up the cuts I had to made to provide clearance for the bracing
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I'm really impressed with the quality of Laurie's welds, and the final fitment we ended up with.
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I also found the source of the rear-end clunk. I had assumed that the PO had actually mounted the battery. Silly me, thinking people care about securing batteries that are right next to gas tanks.
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My extinguisher is supposed to be here mid-week, and I still haven't heard back from saferacer.com as to when they can deliver. Does anyone know of any motorsport shops I can drop in to and buy a reasonably-priced M/L sa2010 helmet if they fail me?

Re: The Breakup (Miata build)

Posted: Tue May 13, 2014 3:26 pm
by walterclark
I have ordered from saferacer in the past and found them to be reliable, though I was never in a big hurry so cant comment on speed.

You might call a couple of the local speed shops that are listed as retailers by G-Force and see if they have something in an SA2010 that you can afford.

Ciotti Racing Products Dover 603.743.4333
Johnson's Speed Concord 603.225.5799
One Stop Toy Shop Epping 603.679.9800
Pro-Street Unlimited Manchester 603.647.1919
Tim's Speed & Custom Nashua 603.883.2700

Or even look for a cheap temporary deal on and SA2005 like these: http://gforce.shptron.com/c/helmets_sne ... 05-helmets. Not sure how fast they could get you one though. Saturday is only 3 business days away. I know I bought a Hans a few years back from HMS on Tuesday before an event and while they had to order my size they arranged for an overnight FedEx direct to me from Hans. Trouble is someone at Hans decided to save HMS a few bucks and they shipped it some way that took until Saturday (I was at Ascutney) to arrive. So even well laid plans can go amiss.