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Discussion Starter #1
Question for those of you that have run earlier (1981 and older) Spiders in Chump, Lemons or SCCA...

In regards to the roll cage, we are having a difficult time determining the location of our rear stays. Do we go through the wall to the tie them in on the panel where the strut towers are located or do we keep them inside the cabin and tie them into the front part of the rear wheel wells? If we keep them inside we are very close to an "illegal" angle for Lemons and Chump but if we go into the trunk we now have to have a fuel cell because we are into the fuel tank compartment or fabricate a panel that utilizes gromets around the bars....

Just wondering if anyone can make a suggestion or provide some pictures. There are several pics of Spiders with cages but not many interior shots to see where to place the spreader plates. Thanks in advance!
 

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Question for those of you that have run earlier (1981 and older) Spiders in Chump, Lemons or SCCA...

In regards to the roll cage, we are having a difficult time determining the location of our rear stays. Do we go through the wall to the tie them in on the panel where the strut towers are located or do we keep them inside the cabin and tie them into the front part of the rear wheel wells? If we keep them inside we are very close to an "illegal" angle for Lemons and Chump but if we go into the trunk we now have to have a fuel cell because we are into the fuel tank compartment or fabricate a panel that utilizes gromets around the bars....

Just wondering if anyone can make a suggestion or provide some pictures. There are several pics of Spiders with cages but not many interior shots to see where to place the spreader plates. Thanks in advance!
I don't have a Spider, but I've seen a couple running in LeMons, and may be able to get you some pictures. (I do have a Berlina that's all caged up).

Short answer, go through the rear firewall.

Where are you located? I know of a Spider in the Boston area you could take a look at, and another out here in Northern California, both have run races this year and meet the current rules.

bs
 

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Discussion Starter #3
Thanx for the reply BS! Unfortunately I am in Houston but we were leaning towards the firewall route just due to angle. Pics would be great if you have them. We are actually building a mock up cage from 2x2 lumber to help us figure out the correct angles and measurements.
 

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Richard Jemison
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Roll cage

Don`t get too hung up on the "angles" so much as the design relative to front (forward) bracing and rear bracing is what the tech people are looking at. There is no "one specification" you will be held to. However the front and rear bracing should be as close to the top of the hoop as possible or on the cross member itself.

The stronger area aft of the drivers seat is the wheel tubs where they approach the vertical trunk panel. It is heavier material and tied into many other steel pannels in the chassis. That is where I tied in the rear braces.
On the Duetto`s overweight and overdone cage that I cut out of it, the cage`s rear braces went through the trunk panel and were welded next to the shock mounts in the raised area of the trunk.

The rear of the Spiders (all Alfas) are weak structurally, and perhaps if safety outweighs the weight penalty running the rear supports through the rear (vertical) panel (with a reinforcing plate welded to the tube and sheet metal there) continuing to the rearmost area of the trunk with a tubular crossmember there to prevent rear crash intrusion would be a decent design.
The cars are light in the rear anyway.

In any event, use the lightest tubing material that is allowed for the cars weight configuration in the SCCA GCR. Their specs ore still "over adequate"

There are roll cage build pics in both of the links below:

http://www.alfabb.com/bb/forums/motorsports/146464-old-alfa-racer-pics-so-west-div.html

http://www.alfabb.com/bb/forums/spider-1966-up/74007-spider-improvement-effort.html
 

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Hi Richard,

In the case of LeMons, there is a specification, and the above would not pass. They specifically won't allow rear stays to extend beyond the rear wheel arches, yet at the same time the rear stays must have a minimum angle of extension from the main hoop.

I can't speak to other racing groups or sanctioning bodies, but in LeMons they're pretty clear on what they're looking for, and they will fail you if you don't comply.

bs
 

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Richard Jemison
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Cages

Brian, I have never encountered a sanctioning body who would not approve a cage designed and meeting the SCCA`s GCR specifications.

Given the mess I have seen in the "LeMons" type cars I can`t imagine their tech people being too critical...
Rj
 

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Brian, I have never encountered a sanctioning body who would not approve a cage designed and meeting the SCCA`s GCR specifications.

Given the mess I have seen in the "LeMons" type cars I can`t imagine their tech people being too critical...
Richard,

In this case, you'd be wrong. On safety they are extremely critical. Are you seeing unsafe cages on cars that have run LeMons, or cars that are being build for LeMons?

I've seen them force teams to make fixes on site before allowing them to race, anything from minor tweaks to some teams cutting out the entire cage and starting over. (One of the things I love about LeMons is some of the stuff that get's built or repaired at the track, under duress).

The cars may look like total sh*tboxes, and in many cases they are, but I can assure you the LeMons safety crew takes things very seriously, and they *will* fail you if your safety equipment doesn't comply.

Oh, and they inspect every car at every race. There is no notion of a log book with a one time inspection. We've raced our Milano 25 times in LeMons, we are on good terms with all of the LeMons guys, and we still get scrutinized at every race.

bs
 

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Discussion Starter #8 (Edited)
Richard, the pics give me some pretty good ideas. And to BS's point...he is correct. I have seen teams fail with "$2k professionally installed" cages due to improper placement and minimum angle requirements not being met. Some are able to fix them and some just wasted 6 months of work and several thousands only to wait until next race.

Most "crap cans" are common cars with common cages. There are even some companies that make U-Weld it pre fabricated Lemons cages due to their repeat appearances in Lemons. The Smaller cars (Alfas, MGs, Minis, etc.) all present unique challenges to to cage compliance simply due to smaller cabins meaning tighter angles and limited space. We are cutting what we can out of the interior panels and interior door skins to make room for spreader plates along the frame rails and NASCAR bars on the driver's side. We are also going to fabricate new panel where we go through the rear firewall for the rear stays. I will get some pics of the car and mock cage this weekend and post them up.

I've heard both good and bad things about Spiders in Lemons and the bad is the limited, common race parts. The good is having a surgeon / engineer who owns 3 Spiders, donated the car for the race and is on our team ;-)


Here is the link from the rules page of Lemons:

http://www.24hoursoflemons.com/prices-rules
 

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The reason for the cage not extending past the rear wheel arches in LeMons is that they want the OEM crush zones to be effective in absorbing crash energy.

There is verbiage about this in the rules.

Due to the increasing speed differentials between the fastest and slowest cars in LeMons I have witnessed some really hard crashes that have used up every inch of this structure..

I think a lot of people would be surprised by how fast the top of the field in a LeMons or Chump car race is.

Greg
 

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Richard Jemison
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Roll cage

Read that section of the "Rule book" re cages.
Said as close to 45 degrees as "REASONABLE"
(which opens the door to different designs obviously)

My point has been is it reasonable to attach a bracing tube to something with no structural integrity just to have 45 degrees?

I have no dog in this hunt. No further input.
 

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Read that section of the "Rule book" re cages.
Said as close to 45 degrees as "REASONABLE"
(which opens the door to different designs obviously)

My point has been is it reasonable to attach a bracing tube to something with no structural integrity just to have 45 degrees?

I have no dog in this hunt. No further input.
Hey Richard,

I can't argue with you here. My only comment was in response to your comment that LeMons wouldn't fail a cage built to SCCA GCR rules. They will, and have, if it doesn't also meet their set of rules. The two main areas where people with other cages have issues with LeMons is with the spreader plates and the rear stays.

Yeah, I'd like to think a cage built to SCCA GCR rules would be ok, but that's not a guarantee.

bs
 

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spider cage

this is my 3rd attempt to do this, hopefully will not post 3 times. if it does, sorry.
we are running an 85 spider in the NE. we had the cage professionally built. it was expensive, but if you divide up between team members, not too bad. we did not go light. we went strong - main structure is 1.75" DOM seamless. i do not regret the few extra pounds.
our thought was that if anything goes bad we are WALKING AWAY, not jaws of life, dragged away on a gurney. the spider is tiny - and slow. do not want to get a 5/6/7 liter GM up the wazoo w out some structure around you. lemons entries are quite large - 120>180 cars depending where you are entered. you almost never are alone on the track, often in a big clot of cars racing hard. stuff happens. imho, better safe than sorry.
it is an amazing structure - if a little tall. should have gone w a sports fisherman boat theme. height due to fact that we could not settle on a final height so decided to go tall, just in case. oh well, makes it easy to get out of the car.
have not been hit in this car yet - but have been in milanos - and have seen others take big hits. like lift the car right up off the ground hits. so do not regret the extra stucture. besides, the spider is a totally flexible flyer and the cage really stiffens the chassis... all good for handling.
also, we went for a fuel cell. the oem tank is right at the corner of the car - with maybe an inch of space between the fender and the tank? had the cage guy build that as well. lemons will generally accept any oem tank solution, but it made us nervous. we scored the cell used. worked out fine.
in any case, regarding your specific questionL the B pillars will end up right up against the rear seat shelf. not much room from there to the rear bulkhead. hard to get anything near a 45' angle by keeping the C pillars forward of the bulkhead. went through the rear bulkhead and tied to plates welded to the shelf between the shock towers. very robust. fwiw, tech inspectors really like this cage...
you do have to patch the bulkhead but is not that big a deal.
attaching some pics of cage. if you have any further questions about prep or our experiences todate drop me an email.
andy
 

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I like it and it is better than some other Spider roll cage designs I've seen ...
Pete
 

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Discussion Starter #14
Barbone,

Clean design for Lemons! I like the structure! Would it be possible for you to post a pic of the windshield post runners in relation to the inside of the door? We are wanting to run with a slightly less aggressive angle going up to the halo for two of our taller drivers. We removed the windshield completely and will be using a boat screen that is being fabricated for us out of Lexan (including some plastic tear-offs for it as well). If we do that it almost apprears that we will have to cut away some of the front quater panel to do so and we would really like to avoid that if possible. Thanks again for all the input guys!
 

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here are a few pics. basically he built the A pillar to run right along the windwhield frame then turned down to the floor. then spot welded the windshield frame to the pillars.
also, gutted the doors w extreme prejudice. left them just a floppy skin. then welded that to the door jamb(s) and in a nod to practicality, welded in a small section sq tube along the top of the door to give it some support so can get in and out of the car wout crushing the door. the previous owner had used sooo much bondo on the doors, had to grind down almost 1/2" in some places to get to metal so could weld.
 

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Discussion Starter #16 (Edited)
Thanks again! I wish the person that did you cage saved the specs. I'd order one straight from him but I'm sure it was all done custom. Its a great looking cage and we are passing along some of these pics to the machine shop that is going to make ours. That is easily a $2000+ looking cage.
 
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