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Strut Bar PSA


enginerd
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Public Service Announcement:

 

With a new sheriff in town, things have changed with rear strut bars.

 

Background:  the backstays on my roll cage weld straight to the rear shock towers, for years I have had a roll cage bar welded perpendicular between these bars, very close to where they attach to the shock towers. The whole idea, obviously, was "get the benefit of the strut bar by clever placement of roll cage components". In the past, Phil wanted to charge points for it, but I always put my foot down and said that I wasn't exceeding the maximum value-free roll cage and there weren't any rules restricting this particular placement of the roll cage tubes.

 

Fast forward to Brainerd impound, I now have 10 points in my logbook for a rear strut bar. As I understand it, the gist is: "if it looks like a duck and does what a duck does, it gets the point value of a duck even if it's a goose".

 

So, if you have that going on it will be 10 points next time you go through tech. Tech guy (Jay, I think?) said that if I had a full "X" between the backstays it would not have been points.

Edited by enginerd
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17 hours ago, enginerd said:

Public Service Announcement:

 

With a new sheriff in town, things have changed with rear strut bars.

 

Background:  the backstays on my roll cage weld straight to the rear shock towers, for years I have had a roll cage bar welded perpendicular between these bars, very close to where they attach to the shock towers. The whole idea, obviously, was "get the benefit of the strut bar by clever placement of roll cage components". In the past, Phil wanted to charge points for it, but I always put my foot down and said that I wasn't exceeding the maximum value-free roll cage and there weren't any rules restricting this particular placement of the roll cage tubes.

 

Fast forward to Brainerd impound, I now have 10 points in my logbook for a rear strut bar. As I understand it, the gist is: "if it looks like a duck and does what a duck does, it gets the point value of a duck even if it's a goose".

 

So, if you have that going on it will be 10 points next time you go through tech. Tech guy (Jay, I think?) said that if I had a full "X" between the backstays it would not have been points.

Damn Nate, I thought you were one of the non-cheaty E30 guys...😂  Or did you move to the east region? LOL

I'd say your 'clever placement' is still a strut tower brace.

Phil was much too easy to persuade.... (in more situations than just this - great guy, but part of the reason for some interesting rule interpretations)

I like Jay's input - an X would be legal by the rules, and probably would stiffen up more of the chassis than a tower brace bar.

Edited by mcoppola
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2 hours ago, Ron_e said:

If a horizontal bar between and essentially connecting the strut towers is not a strut tower brace then I don’t know what a strut tower brace is.  

 Halaluya brother you got that right !!

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IMHO Nate's configuration isn't really a stretch of the rules.

4 tubes are allowed behind the rear hoop, 2 of which are the required backstays.

Assuming you are going to have these extra tubes end near a joint and not in the middle of a tube there really aren't that many possible configurations.

 

Nate chose to add one extra tube between the rear ends of the backstays, it doesn't touch the chassis anywhere.

Personally, I would think that in an E30 where the only loads going through the rear shock towers are vertical forces from the dampers (springs loads go through the floorpan), this tube isn't even worth it's weight as far as making the car faster. If there was a benefit to stiffening the chassis in this area an "X" using both allowed tubes would be even more effective. 

 

If the naysayers don't like having a horizontal bar at the bottom of the back stays how much of an angle or how far up the tube does it have to be before it's not a strut bar? Purely a judgement call? 

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20 minutes ago, ABR-Glen said:

If the naysayers don't like having a horizontal bar at the bottom of the back stays how much of an angle or how far up the tube does it have to be before it's not a strut bar? Purely a judgement call?  

 

The answer is obviously "email Jay".

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31 minutes ago, ABR-Glen said:

IMHO Nate's configuration isn't really a stretch of the rules.

4 tubes are allowed behind the rear hoop, 2 of which are the required backstays.

Assuming you are going to have these extra tubes end near a joint and not in the middle of a tube there really aren't that many possible configurations.

 

Nate chose to add one extra tube between the rear ends of the backstays, it doesn't touch the chassis anywhere.

Personally, I would think that in an E30 where the only loads going through the rear shock towers are vertical forces from the dampers (springs loads go through the floorpan), this tube isn't even worth it's weight as far as making the car faster. If there was a benefit to stiffening the chassis in this area an "X" using both allowed tubes would be even more effective. 

 

If the naysayers don't like having a horizontal bar at the bottom of the back stays how much of an angle or how far up the tube does it have to be before it's not a strut bar? Purely a judgement call? 

 

I would agree that that bar probably doesn't do squat - just giving a friend a hard time...

@ABR-Glen makes a great point here. I can't believe the number of cars i see with tower braces, or backstays going to the shock towers or shock mounting points. Unless the car has coilovers, the bigger benefit is terminating the backstays just above the spring mount, not the shock mount! I build a lot of roll cages, and unless the car has rear C/O's, the backstays always go to the floor,  just above the rear spring perch/cup.   (I've even sunk a vertical tube under the backstay mounting plate to the top of the spring cup, but don't tell anybody this little trick... 😯)

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Sorry, can’t have an E30 specific rule.  All rules apply to all cars and some cars are running coilovers.  

 

If it doesn’t do anything then why have the item and the ensuing argument about the function of the item as it pertains to all cars?

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19 minutes ago, Ron_e said:

Sorry, can’t have an E30 specific rule.  All rules apply to all cars and some cars are running coilovers.  

 

If it doesn’t do anything then why have the item and the ensuing argument about the function of the item as it pertains to all cars?

He wasn't saying "it should be allowed because it doesn't do anything" he was mocking me for having a 4 pound steel bar on my car which doesn't do anything!!

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Tech is coming together to make many things clear very soon . 

 I know what I think but I'll seek opinions - how close to a strut ,shock, tower can a horizontal bar be and not be valued at points ? 

  Anytime anyone has concerns, sugestions or ideas email the tech line ..  how many of you guys have applied for the tech committee ? 

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1 hour ago, Ron_e said:

If it doesn’t do anything then why have the item and the ensuing argument about the function of the item as it pertains to all cars?

"My header doesn't actually help the power output so I don't think it should be counted." ;)

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8 minutes ago, pintodave said:

Ugh. I think there will be a lot of these situations over the next 6 months.....  I hope not, but highly unlikely... 

 

@enginerd this value was added to your car post race, or was this for the next day of a double 7? 

It was added post race on Sunday, was not identified on Saturday. Glad they didn’t try to DQ because it wasn’t claimed. I had 489 points on annual tech from NCM so they made it 499. 

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3.2.12. Roll-cages may not have more than four (4) tubes installed behind the main hoop and two (2) of these must include the main-hoop rear-support (backstay) bars without value add.

 

@enginerd, do you have more than 4 tubes installed behind the main hoop including 2 of them being back stays?

 

The rule looks pretty simple. 

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2 minutes ago, red0 said:

3.2.12. Roll-cages may not have more than four (4) tubes installed behind the main hoop and two (2) of these must include the main-hoop rear-support (backstay) bars without value add.

 

@enginerd, do you have more than 4 tubes installed behind the main hoop including 2 of them being back stays?

 

The rule looks pretty simple. 

Only 3, but I also don’t care anymore because I will just retech without it at the next race. 

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31 minutes ago, enginerd said:

It was added post race on Sunday, was not identified on Saturday. Glad they didn’t try to DQ because it wasn’t claimed. I had 489 points on annual tech from NCM so they made it 499. 

 

Wow. I have a problem with that. Your log book and valuation was performed by a Champcar official (Phil), if the new tech official has a problem with how it was previously valued, that should be a fix by next event item. 

 

Or just claim all 2018 techs invalid and make everyone re-tech so there are no surprises post race based on a difference of staff interpretations. 

 

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53 minutes ago, pintodave said:

Ugh. I think there will be a lot of these situations over the next 6 months.....  I hope not, but highly unlikely... 

 

@enginerd this value was added to your car post race, or was this for the next day of a double 7? 

The aftermath of all the "ask Phil's" ... 

cant wait for the tech advisory committee to hopefully clear up and document a lot of things. 

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13 minutes ago, mcoppola said:

The aftermath of all the "ask Phil's" ... 

cant wait for the tech advisory committee to hopefully clear up and document a lot of things. 

 

Exactly. I'm Switzerland on the whole thing, including this interpretation for @enginerd, but to take a rules interpretation by a Champcar official, right or wrong or indifferent, and re-value it post race just doesn't seem appropriate for a item that was declared or received interpretation (meaning he wasn't hiding it, like a 3.5 under 3.0 plastic). 

 

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1 minute ago, pintodave said:

 

Exactly. I'm Switzerland on the whole thing, including this interpretation for @enginerd, but to take a rules interpretation by a Champcar official, right or wrong or indifferent, and re-value it post race just doesn't seem appropriate for a item that was declared or received interpretation (meaning he wasn't hiding it, like a 3.5 under 3.0 plastic). 

 

I think he may have done it differently if my TCV was over 490 going in to impound. Because 10 points wasn’t going to give me laps, it was a moot point and really was equivalent to ‘retech by next event’. 

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