Pics of your SN95 cages?

[ScotWithOne_t]

I am interested in seeing pictures of your roll cages in SN95 Mustangs. Specifically where the main hoop connects to the floor, and where the rearward braces connect to the floor. This is not for an AI car, but an HPDE car, but I figured this would be a good place to ask for advice since there are probably many SN95 owners here, and you ALL have roll cages.

 

Thanks,

-Scot

[white_2kgt]

Bunch here,

http://www.2kgt.com/item.php?itemid=144

 

Couple words of advice, have the main hoop laid back a few degrees towards the rear. This will bring it more in-line w/ the B-pillar, and make sure they get the A-pillar bars up tight against the a-pillar. Don't even think about attaching the rear down bars to anything other than the frame rails in the rear, not the wheel wheels like the autopower bars do, those are WAY to weak for a cage.

 

Yes, I know the diagonal isn't legal, it's being fixed.

[ScotWithOne_t]

Thanks for the response, and pics. Couple questions/comments though:

 

Couple words of advice, have the main hoop laid back a few degrees towards the rear. This will bring it more in-line w/ the B-pillar,

 

I was wondering if it would be okay to tilt the hoop back some, but it sounds like that is an acceptable practice? I may need to do that anyway in order for there to be enough room so the seat doesn't hit the harness bar.

 

and make sure they get the A-pillar bars up tight against the a-pillar.

 

there will be no a-pillar bars. This is a Competition Engineering 8pt roll bar kit that I am welding in myself, not a full cage.

 

Don't even think about attaching the rear down bars to anything other than the frame rails in the rear, not the wheel wheels like the autopower bars do, those are WAY to weak for a cage.

 

hmm... yours are not connected to the frame rails. unless the rear shock towers are considered to be part of the frame rails on a unibody car. I'm not quite sure how I will get the rear bars to that location though, since the rear bulkhead is in the way. Looks like you removed yours, along with the rear decklid. I may just use a holesaw to cut holes where I need them in the bulkhead.

[fireball25f500]

Here is a link to a friend's AS Work in Progress.

 

http://www.geocities.com/rgebhardt9/cage.html

[white_2kgt]

hmm... yours are not connected to the frame rails. unless the rear shock towers are considered to be part of the frame rails on a unibody car. I'm not quite sure how I will get the rear bars to that location though, since the rear bulkhead is in the way. Looks like you removed yours, along with the rear decklid. I may just use a holesaw to cut holes where I need them in the bulkhead.

 

That is correct. They will be though. The cage has been cut out of that car in the pictures and is being prepped for another car. I would build another one w/ a laid back main hoop and better A-pillar bars, but it's 'ok' and I'd rather spend the $$$ in brakes.

[ScotWithOne_t]

That is correct. They will be though. The cage has been cut out of that car in the pictures and is being prepped for another car. I would build another one w/ a laid back main hoop and better A-pillar bars, but it's 'ok' and I'd rather spend the $$$ in brakes.

 

So are you saying that attaching it like you had in the pics is not good? I've seen pics of many a mustang where they run a strut brace between the rear stut towers, then just weld the rearward rollbar braces to the horizontal strut brace. welding it directly to the strut tower seems like it would be better to me...and besides...i don't think I will be running a rear STB.

[mcmmotorsports]

 

Yes, I know the diagonal isn't legal, it's being fixed.

 

Hey Chad, hate to tell you this, but there were a BUNCH of cars at VIR two weeks ago with the exact same diagonal problem that you have.

Not just Mustangs, but Bimmers and Honda's too.

[nape]

Can you guys find where it's quoted in the CCR where a 1pc main hoop diagonal is required? I was trying to argue that point a while back then couldn't find the section in the CCR.

 

Thanks.

[Grumpy]

Can you guys find where it's quoted in the CCR where a 1pc main hoop diagonal is required? I was trying to argue that point a while back then couldn't find the section in the CCR.

 

Thanks.

 

The CCR states where each end of the bar should connect. Driver side head and passenger side floor.

 

15.6.7 Diagonal Brace

At least one (1) diagonal brace shall be used in the same plane as the main hoop. One

end of the diagonal brace shall attach to the corner, or horizontal part, of the main hoop

above the driver’s head, within twelve (12) inches of the driver’s-side corner. The other

end of the diagonal brace shall attach to the mounting plate (or to the main hoop as

close to the mounting plate as practically possible) diagonally opposed to the driver’s

head (passenger floor).

[white_2kgt]

That is correct. They will be though. The cage has been cut out of that car in the pictures and is being prepped for another car. I would build another one w/ a laid back main hoop and better A-pillar bars, but it's 'ok' and I'd rather spend the $$$ in brakes.

 

So are you saying that attaching it like you had in the pics is not good? I've seen pics of many a mustang where they run a strut brace between the rear stut towers, then just weld the rearward rollbar braces to the horizontal strut brace. welding it directly to the strut tower seems like it would be better to me...and besides...i don't think I will be running a rear STB.

 

no, it's really fine. that area is plenty strong, especially when connected together w/ a bar. just that tying into the frame rail would be stronger. I'm going to 'box' in the shock tower, connect that to the frame rail and then attach the cage to that. I mainly was trying to say DON'T attach the down bars to the wheel wells, like many a roll bar-in-a-box's do.

[white_2kgt]

 

Yes, I know the diagonal isn't legal, it's being fixed.

 

Hey Chad, hate to tell you this, but there were a BUNCH of cars at VIR two weeks ago with the exact same diagonal problem that you have.

Not just Mustangs, but Bimmers and Honda's too.

 

Don't know why you hate to tell me, I'm going to fix mine to comply with the rules, won't be an issue anymore. Was it an issue for them during tech?

[mcmmotorsports]

 

Don't know why you hate to tell me, I'm going to fix mine to comply with the rules, won't be an issue anymore. Was it an issue for them during tech?

 

Well, I hated to tell you because a lot of other cars had it like yours and it according the the CCR and what I saw, I guess it is legal and now you went ahead and did all that work for possibly nuttin'

[white_2kgt]

 

Don't know why you hate to tell me, I'm going to fix mine to comply with the rules, won't be an issue anymore. Was it an issue for them during tech?

 

Well, I hated to tell you because a lot of other cars had it like yours and it according the the CCR and what I saw, I guess it is legal and now you went ahead and did all that work for possibly nuttin'

 

Well, according to the rules it isn't legal. I'm sure plenty of cars get though tech w/ it that way, I did, I'm just not going to take the chance again.

[ST#97]

 

Don't know why you hate to tell me, I'm going to fix mine to comply with the rules, won't be an issue anymore. Was it an issue for them during tech?

 

Well, I hated to tell you because a lot of other cars had it like yours and it according the the CCR and what I saw, I guess it is legal and now you went ahead and did all that work for possibly nuttin'

 

Well, according to the rules it isn't legal. I'm sure plenty of cars get though tech w/ it that way, I did, I'm just not going to take the chance again.

If you guys are saying the main hoop diagonal that goes from driver head to passenger floor is to be one continuous piece of tubing, then 90% of all our cars in Texas are wrong and those were signed off on at nationals last year....? Mine is this same way and was tech'd by Ryan in our region who did the tech at Nationals....

[white_2kgt]

 

Don't know why you hate to tell me, I'm going to fix mine to comply with the rules, won't be an issue anymore. Was it an issue for them during tech?

 

Well, I hated to tell you because a lot of other cars had it like yours and it according the the CCR and what I saw, I guess it is legal and now you went ahead and did all that work for possibly nuttin'

 

Well, according to the rules it isn't legal. I'm sure plenty of cars get though tech w/ it that way, I did, I'm just not going to take the chance again.

If you guys are saying the main hoop diagonal that goes from driver head to passenger floor is to be one continuous piece of tubing, then 90% of all our cars in Texas are wrong and those were signed off on at nationals last year....? Mine is this same way and was tech'd by Ryan in our region who did the tech at Nationals....

 

yes that is what we are saying, just b/c a bunch of people are doing it doesn't make it legal, so until the rule is rewritten, mine's getting fixed.

[mcmmotorsports]

Chad, can you show me where it says that it must be 1 continuous piece?

[ST#97]

well, it sounds like someone needs to rule now so those of us that are going to be at nationals or fabricating cars now can fix this....hate to see half the field get disqual'd!!!!

[Adam Ginsberg]

So are you saying that attaching it like you had in the pics is not good? I've seen pics of many a mustang where they run a strut brace between the rear stut towers, then just weld the rearward rollbar braces to the horizontal strut brace. welding it directly to the strut tower seems like it would be better to me...and besides...i don't think I will be running a rear STB.

 

This particular method of cage construction was addressed 2+ years ago during a friend's build up - welding the required rear braces from the main hoop down to a horizontal bar ( instead of welded to mounting plates ) situated between the shock towers is not permitted in the CCR's:

 

2007 NASA CCR's, rev 2007.13 Edition, Section 15.6.13 Mounting Points

 

The roll cage shall be mounted to the floor of the car in six, seven, or eight points. The cage shall not go through the firewall. The seventh and eighth points must attach to the firewall or front fender wells. All cage attachment points must be mounted to plates. Each required cage bar shall terminate on a plate with a 360 degree weld to the mounting plate, except as specified in Section 15.6.14.B. There shall be only one (1) mounting “pointâ€

[ST#97]

 

90%, Matt?? Have you personally inspected all the cars competing in Texas? I don't think so.....

 

However, no where in section 15.6.7 doesn't specifically state it has to be one contiuous piece. One could infer that, but it doesn't actually say it. That could leave the interpretation to each Scrutineer - and that could be very subjective.

 

 

 

 

as for the horizontal bar passing between the "uprights" of the main hoop, I sort of figured all this time that this bar was to aid in deterring the collapse of the upright in a side impact and the diagonal bar was to keep the upper portion of the cage intact in a roll over.

 

I am also pretty certain someone in the SCCA or cage building business figured this out a long time ago and should be able to figure it out pretty quickly. At the very least, so as to prevent confusion at nationals, will there be an official ruling on this or does JWL and the gang even know about this thread? If not, let's run it up the flag pole and get an answer instead of chasing ghost interpretations of the rule and causing undue panic.

Edited April 7, 2007 by Guest

[ST#97]

yes that is what we are saying, just b/c a bunch of people are doing it doesn't make it legal, so until the rule is rewritten, mine's getting fixed.

 

Chad, are you being overly paranoid since you have been on your roof this year or has there been a history of an actual problem of someone not getting a green flag on this...?

 

Thanks!

[Adam Ginsberg]

Adam, it called an generalization...something like someone saying YOU are an idiot. Do we know it for sure? no....but all the signs point to it...

 

Nice work, Matt. Great way to drag an informative thread into the trash heap.

[ST#97]

actually no offense to chad because we have sort of built cars around the same timeline and shared some ideas along the way....but I don't think there is an overall good list of tech in this thread as it sounds like we are going on rumors and not facts regarding the "one Piece" bar.

 

Otherwise, it was just a simple attack on you....which nobody gives a sh!t about anyway..... Have a nice day!

[Frank Corkran]

I am also pretty certain someone in the SCCA or cage building business figured this out a long time ago and should be able to figure it out pretty quickly.

 

They did. From the SCCA 2007 GCR:

 

9.4.2 SHOWROOM STOCK ROLL CAGE

D. Main Roll Hoop:

1. Main roll hoop (behind the driver) shall extend the full width of the driver/passenger compartment and shall be as near the roof as possible. It shall incorporate a diagonal lateral brace to prevent lateral distortion of the hoop ( See Figure 8 ). Any number of additional reinforcing bars are permitted within the structure of the cage. It is required that the horizontal brace behind the driver’s seat (described in Section 9.4.2.J.) continue from the diagonal to the passenger side main hoop upright or that a second diagonal be installed in the main hoop.

 

Figure 8 referenced explicitly shows the diagonal as 1-pc and the horizontal bars as 2 separate tubes (welds and all). Section J requires the horizontal on the driver's side from the main hoop to the diagonal "In order to provide a secure seat back support..." The requirement above for the horizontal bar to continue on the passenger side was added within the last year or two.

 

Figure 8 is referenced by all the various SCCA production based race class rules and the same main hoop/diagonal/horizontal brace verbage is also included in each rule set.

 

The 2007.13 EDITION NASA CCR 15.6.7 calls out the diagonal as a required bar, but I can't find any mention of a required horizontal bar in the main hoop. 15.6.22 Seat Back Support doesn't specifically mention a horizontal bar, just that "A seatback support must be made to hold the seat from going back in the event of a crash."

 

15.6.7 Diagonal Brace

At least one (1) diagonal brace shall be used in the same plane as the main hoop. One end of the diagonal brace shall attach to the corner, or horizontal part, of the main hoop above the driver’s head, within twelve (12) inches of the driver’s-side corner. The other end of the diagonal brace shall attach to the mounting plate (or to the main hoop as close to the mounting plate as practically possible) diagonally opposed to the driver’s head (passenger floor).

 

The italics I've added above also seem to indicate that the diagonal will have only two ends, each attached to the main hoop. The implication is that this required bar must be 1-pc.

 

Section 15.5 Driver restraint system doesn't call out a horizontal bar either, only:

 

6. The shoulder harness shall be mounted behind the driver and above a line drawn downward from the shoulder point at an angle of no more than twenty (20) degrees with the horizontal.

7. The seat, seat holes, and attachments to the seat are not permissible “harness guidesâ€

[ST#97]

Frank, thanks for the info...good stuff.

 

Now JWL, can we get a ruling so I can figure out whether or not to go get a cutting wheel and start making some sparks!

 

Thanks!

[ScotWithOne_t]

Do you guys see any problem with mounting the main hoop on the raised section on the leading edge of the rear seat?

 

 

The kit came with 6"x6" mounting plates, so I would probably put a 90° bend in them and place them on top of that raised part. The rules for roll bars in the HPDE section seem pretty sparce, so I'm assuming that details like mounting locations, whether or not the diagonal brace is one piece, etc. are not going to be considered by the tech inspectors. As I understand it, anything mentioned in section 15.6 of the CCR applies ONLY to full cages, however I'd like to follow it somewhat since I'm sure the rules in 15.6 are there because it is the best (safest) way of doing things.