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Regarding strut bars.
9.3.8.9. Any bolt-in or welded strut or shock tower brace is permitted, unless specified in these
regulations. Attachment points are limited to the shock towers. This single bar is not a
part of the car’s roll cage structure and is not bound by CCR section 15.6.
That means the following is still illegal correct?
I think that is legal. The sentence you highlighted was saying that the strut bar would not be considered part of the roll cage, and thus would be exempt from the 15.6 rule.
[quote=rules]Chassis stiffening is a side benefit of a good roll cage system, but it is not the intent of
these rules. Parts of the cage deemed by the Chief Scrutineer, to serve no practical
purpose other than chassis stiffening may be considered in violation of the intent of
these rules (Note: Some class rules allow for chassis stiffening.).[/quote]
I think originally the strut brace would violate that rule.
Simon, where did you get that picture of my car?
Clarification: mine is painted black. If it makes a difference, mine was done in 2005 before the rules were clarified about braces and subsequently reclarified this year 2011 about braces. But, since we’re both asking the same question about braces, I guess it isn’t clarified?
If you need photos of other cars with this type of brace before the brace rule before the subsequent brace rule let me know.
Regards, Robert Patton
Patton wrote:
[quote]Simon, where did you get that picture of my car?
[/quote]
This is in a car in Indy that my mechanic owns. He is thinking of selling it and I said I would help him. I’m just trying to determine if it is a good candidate for spec E30 and what would have to be changed.
“attachment points are limited to the strut tower”
Isn’t the bar above clearly attached to more than the strut tower?
Elephant4 wrote:
Simon -
I think it is fine. But here is my draft 2012 rule clarification.:laugh:
9.3.8.9. Any bolt-in or welded strut or shock tower brace is permitted, unless specified in these regulations. Attachment points are limited to the shock towers. If a welded shock tower brace is utilized but is not an integral component of the car’s roll cage structure (i.e. if such bar is welded to the same mounting plates supporting the roll cage structure but not welded to or in contact with roll cage bars), the bar shall not be considered to be a component of the roll cage structure and the bar’s attachment points shall not be counted towards the maximum number of chassis mounting points specified in CCR section 15.6.13. If a welded shock tower brace is utilized and is an integral component of the car’s roll cage structure, the bar’s attachment points shall be counted but the bar shall not be deemed to violate section 15.6.2 regarding illegal chassis stiffening.
Howzat?
We’re off topic, but if those in the SE scream “low-class, down and dirty cheater,” and don’t like my brace before the brace rule before the brace rule, well, I always carry a sawsall to the track with me.
RP
Foglght wrote:
You are probably better off going to the spring perches anyway so I wouldn’t worry about it. Here is my car.
Steve D wrote:
I’ve already got the clear helium filled unobtanium ones - they are lighter and the helium lifts the front end. It’s like they aren’t even there! :laugh: 
:silly:
wildhorsesracing wrote:
[quote]Steve D wrote:
I’ve already got the clear helium filled unobtanium ones - they are lighter and the helium lifts the front end. It’s like they aren’t even there! :laugh: :silly:[/quote]
jim, don’t you want downforce not lift in the front end? 
kishg wrote:
[quote]wildhorsesracing wrote:
[quote]Steve D wrote:
I’ve already got the clear helium filled unobtanium ones - they are lighter and the helium lifts the front end. It’s like they aren’t even there! :laugh: :silly:[/quote]
jim, don’t you want downforce not lift in the front end? :)[/quote]
Don’t confuse him. He is still trying to figure out why hot pressures of 23 won’t work.
WooHoo… New Rules! I’m going to be head’n back to Whitakers next month and Al’s going to give me a new tub. I just hope I can get the car build before they change again. :laugh: just kidding. My goal is to be at Lowes B) when it warms up I’ll get started with postin sum pix
Witch do you think is a better bumper choice. I’ll be racing in teh SE and MA so I was thinking I’d rock the big metal ones.
IMHO, this blue cage is not legal due to the CCR requirement that says that all required bars must end on a plate. The two downbars from the main hoop are required bars. The reasoning is that the weld of the crossbar will be put in shear (which is weaker) if the downbar is forced backwards. Ending the downbar on a plate would put the weld/bar in compression. I know of at least one car in my region that did this initially and was asked to change it - he just replaced the downbars and made them go directly to a plate on the shock tower. In fact, I think this is a red car that you bought, Simon (not the red one he pictured above).
9.3.8.9 doesn’t help make this blue bar and plate configuration any more legal. The intent is to say that the crossbar is not to be regarded as part of the cage. If it were, it would have to end in close proximity to the downbars, be welded continuously with them, etc.
In Simon’s pictures of the red car/gray cage bars above, the crossbar is part of the cage (and a very nice design for an e30 at that), and not subject to 9.3.8.9 (which only covers crossbars between the strut towers)
thanks,
bruce
Elephant4 wrote:
[quote]Regarding strut bars.
9.3.8.9. Any bolt-in or welded strut or shock tower brace is permitted, unless specified in these
regulations. Attachment points are limited to the shock towers. This single bar is not a
part of the car’s roll cage structure and is not bound by CCR section 15.6.
That means the following is still illegal correct?
[/quote]
Thanks Bruce, that makes sense to me.
leggwork wrote:
[quote]In fact, I think this is a red car that you bought, Simon (not the red one he pictured above).
[/quote]
Yes the cage was modified in that car, just was checking that the new rule didn’t change that. The red car was sold to Kevin Sweeney and he um tested the cage already :ohmy:.
10 min mark
IMHO, NASA rules mirror SCCA. Either cage would be legal in SCCA since any
number of bars can be connected to a mounting plate. The fact that the down tubes
terminate at the cross bar is immaterial. The cross bar is part of the cage (blue
bars) and therefore can mount to any mounting plate with any number of bars mounted
to the same point. Note, there must be some variation allowance for access for
welding. Also note, the rear cross bar does nothing for chassis stiffness or suspension
pick up points. The cage should be mounted to the spring perches as with the other
car (and they are really a little too far rearward).
As an experiment, I installed my front strut brace with 22ga sheet metal for the last
Barber race and the ARRC. I use the curbs a lot, really a lot at RA. No deflection on the
installation what so ever. Removed the brace to save the weight over the motor. YRMV. Chuck
So, what you are saying is that you believe the blue cage picture is legal, but not necessary.