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alwaysinboost

PT specific cage build help needed

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alwaysinboost

I'm building a new (to me) PT/TT car for next season and wanted to see some examples of cages built to the rules of the class, so I don't build something illegal and/or unsafe.

 

I feel like i have a very loose understanding of what is and isn't allowed. Per the rules, I can have 6 points of attachment to the chassis, since this is a sedan those will be at the base of the A & B pillars and also the rear strut tower. Plus an additional 2 points of attachment for either two foot-well bars or two bars that attach to the firewall, one on each side. is there a benefit to either option for the last two attachment points?

 

for driver side protection, what are the advantages of nascar bars over X door bars? From the rules it sounds like you can only attach nascar bars to the drive side without incurring points, is that correct or can I do nascar bars on both sides?

 

from the rules "Additional bars and/or gusseting within the structure of the cage are permitted without a TT Modification Point

assessment.", does that mean I can go hog-wild with gussets and extra connecting bars so long as they terminate within the existing cage and not on new chassis points?

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CRallo

Sounds like you are most of the way there. Within the allowed attachment points you can indeed go hog wild. Regarding the extra forward bars; the lower bars are more about preventing intrusion to the driver's feet and the upper bars are more about attempting to stiffen the chassis. The former does a better job of doing both if designed properly. A NASCAR style bar is allowed on both sides, the sticking point is the extra attachments. I am cautious about tying the door bars to the chassis because some sanctioning bodies don't allow that for certain classes. Depends on intended and for seen use.

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CRallo

And to clarify, yes it is correct that only the driver side door bars may be tied to the chassis directly.

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kbrew8991

there's an unwritten rule about how high the top of the forward attachment for foot protection can be - Terry @ Vorschlag(sp?) got caught out by it being unwritten if you want to pull up his build thread and saga about that.

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CRallo

Nascar bar vs X bar is a bit like religion or oil...

 

Nascar bars are prolific mostly just in the US. Gusseted X bars are the norm elsewhere and usually required by FIA. The best X bar is two solid bent tubes. Some guys will tilt/twist the tubes so they point out in the middle giving the best of both worlds.

 

Most Nascar bars utilized in road racing street cars have an S bend in the door bars around/behind the B pillar. This is BAD, but "everyone" does it anyways to get the most extension into the door while having the main hoop set back. Try to keep the bars straight with no "reverse" bends, these are failure points.

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ILIKETODRIVE
Most Nascar bars utilized in road racing street cars have an S bend in the door bars around/behind the B pillar. This is BAD, but "everyone" does it anyways to get the most extension into the door while having the main hoop set back. Try to keep the bars straight with no "reverse" bends, these are failure points.

621212_orig.jpg?331

 

No double bend and plenty of space.

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TurboShortBus

It's pretty long, but there is a lot of general cage tech in this thread over at Corner-Carvers.com.

 

http://www.corner-carvers.com/forums/showthread.php?t=27556

 

Tip for C-C: Read, re-read, search, read, then ask questions.

 

As for my own cage, I copied the Australian V8 Supercars "COTF" design with a pair of straight side bars, plus the upper half of a typical X arrangement, with short vertical legs that attach to plates on the driver's side rocker beam only. Passenger's side is a standard X arrangement. A half FIA/half NASCAR A-pillar reinforcement bar was added to the driver's side, while both sides have a reinforcement bar between the upper side bars and the main hoop. The LaJoie full containment seat (not shown) was pushed 2" inboard from the stock seat centerline, down to about 2" above the floorpan, and back about 8" or 9" (note how far back the main hoop attaches) for a driving position that is as far away from the side bars, A-pillar, and roof as reasonably possible without cutting the floorpan or transmission tunnel. Note that the setback seating position didn't do much for front/rear weight distribution; prior to the cage installation, the car was 59% front/41% rear, while it is now about 57% front/43% rear, with the majority of the cage being located behind the balance point (about 6" behind the stock shifter), which likely accounts for most of the 2% rearward weight shift. Besides, with the LaJoie seat, it would be impossible to get in/out of the car between the A-pillar reinforcement bar and the head containment without moving the seat back 8"-9".

 

I still would like to add a short angled bar from low on the driver's side of the main hoop to the hoop diagonal/harness bar intersection to brace the bottom of the main hoop from being bent inward in the event of a side impact. Right now, it's like I have a strong garage door with weak track attachments at the jambs.

 

997997_10152953870910214_1230005199_n.jpg?oh=9f391c97ac1e85512aa9e0562d0b39b9&oe=568B01C6

 

Mark

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TurboShortBus
there's an unwritten rule about how high the top of the forward attachment for foot protection can be - Terry @ Vorschlag(sp?) got caught out by it being unwritten if you want to pull up his build thread and saga about that.

A brief explanation:

 

1. Those particular foot-well bars attached at a point that was way too high to provide foot protection (unless the intrusion was coming in above the top of the front tires). I will agree, though, that the rule could have been written a little more clearly.

2. It was determined that those particular foot-well bars performed an additional function, which is not permitted without taking points.

3. The designer, fabricator, and/or installer obviously did not fully read or understand PT/TT classification forms section H.

 

Note that the car owner was afforded a massive courtesy when various points discrepancies (easily found via his widespread internet documentation) were brought to his attention by officials BEFORE the car's first event, and not AT the event, where it would have been disqualified and/or moved up from its intended class of PTC/TTC to PTB/TTB. This allowed changes to be made to the car so that it could compete in PTC/TTC.

 

When in doubt, ask a regional or national director first, THEN start welding.

 

Mark

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kbrew8991

if there's going to be a window defined for those foot protection kickers going forward, then cool. There wasn't one, I don't know that as a regional (now former) I would've made the call as to illegal on those as I couldn't point to any language or past precedent to back up the call.

 

My $0.01

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Arca_ex

 

When in doubt, ask a regional or national director first, THEN start welding.

 

 

 

It is almost laughable that you think that all of the regional directors would have provided the same answer that was given in that situation, since it is exactly how kbrew8991 describes it, unwritten. What happens if you show up to nationals with written approval from a regional director to do what he did? You get DQ'd or bumped up a class despite the fact?

 

 

Two additional attachment points for either two foot-well bars or two bars to the front firewall

(one on each side) may be added without a TT Modification Point assessment.

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kbrew8991

We were/are not all as awesome as Mark.

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Fair
there's an unwritten rule about how high the top of the forward attachment for foot protection can be - Terry @ Vorshlag got caught out by it being unwritten if you want to pull up his build thread and saga about that.

Unwritten, indeed.

 

A brief explanation:

 

1. Those particular foot-well bars attached at a point that was way too high to provide foot protection (unless the intrusion was coming in above the top of the front tires). I will agree, though, that the rule could have been written a little more clearly.

2. It was determined that those particular foot-well bars performed an additional function, which is not permitted without taking points.

3. The designer, fabricator, and/or installer obviously did not fully read or understand PT/TT classification forms section H.

No, I read the rules, and only made one mistake - the passenger side attachment bars for the NASCAR style door bars on that side.

 

cage-changes-M.jpg

 

I don't agree with this particular rule as written - it encourages people to make one side of a cage less safe than the other - but I did make that mistake... Shame on me.

 

DSC_8615-M.jpg

 

Which has since been fixed (above) and that I shared in my build thread, so nobody else made the same mistake. But the main part of that 5-part Mystery Internet Protest protest on the cage I didn't agree with, has to do with our two allowed firewall bracing bars:

 

B61G6552-M.jpg

 

The rule about these bars is clearly written, and it does not necessarily agree with your (or Greg's) assessment:

 

ttcagerules-page34-M.jpg

 

There no grey area in the wording there, to me. Its pretty cut and dry: Two bars to the front firewall (one on each side) may be added without a TT Modification Point assessment. Which we did, because these flimsy fiberglass cars have really flimsy fiberglass firewalls. In a crash, this structure needs all the help it can get. Only the outer perimeter of the firewall structure is steel, which is where we landed the bars. Did it look unusual? Sure. Was it done within the wording of the rules? We think so, yes.

 

DSC_8599-M.jpg

 

But Greg ruled against us on that, and we had cut those two firewall tubes out as well, unhappily. I sure hope this car never gets in a big enough crash to have needed those firewall braces.

 

DSC_8615-M.jpg

 

And yes, we smoothed out the cut tubes, as recommended. We're not a bunch of hacks.

 

Note that the car owner was afforded a massive courtesy when various points discrepancies (easily found via his widespread internet documentation) were brought to his attention by officials BEFORE the car's first event, and not AT the event, where it would have been disqualified and/or moved up from its intended class of PTC/TTC to PTB/TTB. This allowed changes to be made to the car so that it could compete in PTC/TTC.

Hmm... It is hard to respond to this, because that statement is both misleading and non-factual. I found out about Greg's sudden interest in my C4 during the very first event we attended, which was well before we had built the roll cage. The concerns then were the OEM replacement shocks we were using (off the shelf $80 Bilsteins vs 25 year old out of production Delco-Bilstein factory shocks) as well as the move to the 1996 BTM brakes, which were 13" vs 12" fronts on the 1992-1995 BTM (but these cars are classed as "1992-96 LT1 Corvettes").

 

DSC_5522-S.jpgDSC_5544-S.jpg

 

The points free front brake upgrade was clearly legal, as anyone with basic 3rd grade reading comprehension would have learned had they read my extremely detailed build thread. But it pissed somebody off, so they threw paper - in secret.

 

P7B_9131-M.jpg

 

This was one of the five points brought up at the Mystery Internet Protest that was filed later that year. I heard grumblings about this pending protest at the March 2015 NASA Texas event we attended, after we had built the roll cage. None of my competitors threw any paper on the car then and we had clearly shared everything for the world to see. We had motor problems at that event that sidelined the car for the rest of the NASA season, but that didn't slow down the Mystery Internet Protester.

 

That seems to be the rub - sharing our build thread brought undue scrutiny from some Armchair Quarterback, who then wrote a detailed Protest to Greg, in secret, about FIVE issues they noted on my car that were shown in our build thread, only one of which was a real mistake (but as non-competition enhancing as you can get - the door bars). But that's what we do - we share all of our shop builds - in the hope that we reach people who have never thought about racing with NASA, or maybe was inhibited by the costs of a TT build. This was our cheapest TT build to date (other than the GRM $2011 car we built that I ran in TTU a couple of times).

 

DSC_8298-M.jpg

 

When in doubt, ask a regional or national director first, THEN start welding. - Mark

You see this remark here? a little snippy, yes? That's a NASA Regional Director being a bit condescending and patronizing. Against someone he knows owns a business in motorsports.

 

B61G6520-M.jpg

 

Just so you know I had TWO different NASA Texas race Directors come by my shop, inspect the cage, and look at the wording in rule 8.3.H before it was final welded. They both missed the passenger side bars (because its illogical, and only applies to TT letter classes), as did I, but both agreed that our forward firewall tubing should be deemed legal with 8.3.H, as the wording was clear in the rule about that.

 

B61G6174-M.jpg

 

We're not just a bunch of yahoos working out of a barn here, we build NASA cages for racers. And Pikes Peak cages, and drag NHRA race cages, SCTA/Bonneville cages. Of course we ALWAYS work with tech inspectors from each racing group and get their blessing before we final weld anything. Which we did here, but that Greg over-ruled based on "that's not what we MEANT for the rule to mean" logic.

 

11823150_10205956333565583_2272024844711472190_o-M.jpg

 

Dave Schotz is pretty much the polar opposite of our Mystery Internet Protester. Dave is an open, honest, and respectful competitor. Dave was also racing in TTC this year (just like Mark) and even building a C4, so we could feasibly meet up at a National event this year. He saw something in the our build thread on corner-carvers that was used against me in his 5 part protest, but that the Protester himself missed (could have been 6!)

 

DSC_8975-M.jpg

 

Dave noticed in one of our many pictures we posted that the car had an aftermarket throttle body airfoil. We bought the 24 year old car partially prepped, but I had personally never seen the throttle body with the air intake tube off (my shop manager snapped the pic in question when my techs were working on the car). Yet Dave went out of his way an CALLED ME - a TTC competitor - to let me know that it was a +2 point mod. I had to see for myself, and sure enough - it was in there. We ran the first event with it unknowingly in place (but had the points then for it, so it didn't really mater). This part has since been removed and we shared that openly as well.

 

That is how you handle these matters, without the Mystery Internet Protest. If someone (like Mark here) wanted to "afford a massive courtesy for various points discrepancies" he could have picked up the phone and talked to me - I'm not that hard to find. Or he could have PM'd me here or on corner-carvers, where he apparently read my build thread. It would have taken him 60 seconds...

 

Instead, "whoever" protested me kept it all in secret and sent his mega-protest via the internet. And somehow NASA doesn't allow me to know who protested me when done in secret like this - unless maybe they were a Regional Director with more pull than a normal racer? I can't seem to find this Mystery Internet Protest procedure spelled out in the CCR either.

 

Dozens of people have spoken to me at various events this year and shared their disgust with how this was handled by NASA, so I'm not the only one who thinks this smells funny.

 

Mark's comments only help prove to me what several people have told me: He is the Mystery Internet Protester, who threw paper on our car from thousands of miles away, and did so in secret.

 

Please tell me I'm wrong here, Mark. Tell me a Regional Director didn't pull this janky move??

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Greg G.
Which we did here, but that Greg over-ruled based on "that's not what we MEANT for the rule to mean" logic.

Terry, you should really stop whining on the Internet, it doesn't relay to folks what a great guy you really are or how professional

you are in your builds and with your customers.

 

We don't debate issues of specific vehicle rules interpretations or protests on the Internet, but I guess I need to correct a few of the incorrect statements you are making here, before I shut this down. I don't see why a simple thread about building a cage needs to come to this. First, NASA was made aware of issues

with your build that you believed were No-Points modifications based on your Internet postings and photos, before a competition. Second, NASA made every effort to assure that you would not show up at an event and be disqualified for these issues that we were made aware of before the event. Third, you would have been disqualified for the passenger side bars alone, and NASA prevented you from that embarrassing situation. Fourth, while I handed down the ruling on the front bars that did not go to the firewall (as the firewall is not metal and cannot be welded to), this issue was evaluated by multiple National NASA Executives who assisted in making the determination. Don't throw quotes to my name for statements that I never made. It was determined that your bars did NOT go to the firewall, not the quote you have above. Fifth, the rules state to ask your Director(s) if there are any questions, not to ask some unnamed race directors that are not your Series Directors. Series Directors make determinations about vehicle compliance. Sixth, did you ever consider that just maybe, that the person who informed NASA of your car's potential issues is someone who works for you (or likes you, or is a customer of yours) and knew of the potential issues, but didn't want to see you get DQ'd, and also didn't want you to go on an Internet rant against them, or fire them, etc... It was not a Series Director who brought this to our attention, but there is no doubt that the Series Director would have found these issues when you brought the car to the track, and you would have been disqualified. So, why don't you stop bashing NASA, me, and our Series Directors, and stop making unfounded accusations, and stop trying to play the victim? It is unbecoming of a professional like yourself.

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