Cage Fixing Time

[Ron Earp]

I've got my car apart for a new motor and I'm trying to fix some issues that I have found. First up the cage.

On the driver's side, do you think I'll lose any cage integrity by deleting that lower bar on the driver's side long with the tooth pick bars that attach it to the second bar? I'm searching for weight anywhere I can find it. Yes, I know I have to fix that illegal set mount too, it can't be attached to the cage (cage was done in 1993, Atlanta area).

On the passenger side what is the lightest and safe design I can use that will protrude out into the door so I can gut the door? What I have now is shown and that seat isn't installed in my car, just sitting there for storage purposes.

Thanks,
Ron

http://www.gt40s.com/images/Z/cage2.JPG

http://www.gt40s.com/images/Z/cage1.JPG

[ekim952522000]

Ron I would not change anything On the drivers side it looks very good and safe the way it is. not worth losing the weight IMO.

Passenger side I would basically do the same design you have but make the top one lean every sol slightly into the door.

Just my 2 cents.

[betamotorsports]

On the driver's side, do you think I'll lose any cage integrity by deleting that lower bar on the driver's side long with the tooth pick bars that attach it to the second bar?

Yes.


On the passenger side what is the lightest and safe design I can use that will protrude out into the door so I can gut the door?

"X" bar that points/curves into the door area.

[Speed Raycer]

I wouldn't touch the drivers side unless you're willing to cut it all out and start over.

Assuming that the tubes are the min. size (1.75x.095 instead of .120), IF you feel like you have to do something to the cage, I'd actually take the top bar off and use the next size smaller tube for the top rail and the "toothpicks". In other words, if the bottom bars both meet the min. req., use 1.5x.095 on the top bar/stringers.

Pyramid X on the passenger side is the lightest, but I'd do a pyramid X with a sill bar for the strength (see the Miata impacts from late last year). Again, sill bar and main diagonal on the X would be the required, split bars would be smaller diameter or thinner walled. Don't forget your gussets.

After all is said and done, you'll probably drop 6-8 lbs total.

1.5x.095 =1.426 lbs per foot
1.75x.095 =1.73ish lbs per foot
1.5x.120 = ~ 1.87 lbs per foot
1.5x.065 =.99 lbs per foot

[Xian]

Entirely my $0.02 but if you're looking to lose weight on the car, I'd cut out and redo the bars on both sides. Have you thought about doing a two bar setup like I had done on my car? Gives you most of the weight savings of an "X" design but way more strength along with the legal allowance to gut the doors.

Christian

[Ron Earp]

Hey Christian,

Does Cameron do bars? I think I'm going to do what you and Scott suggest. Cut that stuff out and put new stuff in. 1) for weight savings, 2) so I can legally gut that passenger door. Door guts is heavy!

R

[Xian]

Nope... Cameron isn't a "cage guy". I had my cage done by Chris Schimmel at Competition Cages (up your direction). Here's his site: http://www.competitioncages.com/

Christian

[Ron Earp]

Yep, Chris has done a few cages for me/us over the years. I just was wondering if Conover might be able to do a fix type job. I'm sure Chris can knock this out in no time. I'll get it up to him once I have a trailer to get it there!

[dspillrat]

HI Ron,
On my car, We added a small half loop welded to the pass side cage....12-14 inches long to just reach into door cavity..... seems we lost close to 20 pounds removing the innards of that door..... Course I've managed to put it right back in the drivers seat:shrug:.....
FWIW... I've never really turned down pressure to the rear drums...Have you? I rode around with a regulayer for years, til I relized ....never really use it. Never had problem locking rear drums....unless combined with sloppy downshift.
Wheels are on my list to reduce weight..... Once my 401-K recovers..... Or if my stimulus package application is accepted this time.....
Several pounds to be gained optimizing rules allowance for smaller tubing on none required cage parts........ I do have a shell in the backyard that has the smaller/lighter cage....but havn't needed to finish since my current car showed up out of the blue...
Hope to see you guys on the track this year.......:eclipsee_steering:

david

[Gibson]

What is illegal about the seat mount?

[Gary L]

It appears to be welded to the cage, and fastened to the floor. Therefore, it technically constitutes a 7th roll cage attachment point.

[Gibson]

It appears to be welded to the cage, and fastened to the floor. Therefore, it technically constitutes a 7th roll cage attachment point.

That's illegal? Wow. So if you want to tie the bottom of the seat to the cage, it can't be attached to the floor also? That is going to make for a tricky mount.

[dickita15]

If you mount the seat to the cage instead of the floor the rear is easy and the door side is easy but if you attach it to the tunnel it becomes an extra attachment point. I am also a tech inspector and have issued logbooks to cars that have that kind of setup if I felt the seat was safe and I have never heard of a protest but technically I do not think it is legal.

[Gibson]

That might be something to think about rules wise. It is rare for sure, but occasionally race cars come to rest on their sides, and an unreinforced floor pan offers no protection at all. I don't really see how some tubing under the seat, between the rails and the tunnel would ever be a bad idea.

[Ed Funk]

To quote Kirk et al, "slippery slope"

[dickita15]

I agree Ed but I would love to come up with a solution to be able to mount a seat more securely. If anyone wants to try to write up a rule that would help find a solution I am sure there are plenty of us that would be willing to critique it.

[Speed Raycer]

You can still mount the seat to a frame that attaches to the cage... just takes a little more tubing and some non attached plates to support the seat. http://www.izzyscustomcages.com/images/CustCars/Porsche/BC911/P1010015.JPG

The only corner not attached to the cage is the front right and it has a support pad under it, as does the front left and right rear.

There has been a few instances of a roundy round hornet flipping on its side, drivers side down, and being T boned. Never ends well

[trhoppe]

My seat mount is similar to pic above. Mounted/welded to cage, and the one contact point not welded to the cage is "resting" on the floor.

http://www.tomhoppe.com/misc_pics/seat_mount1.jpg

http://www.tomhoppe.com/misc_pics/seat_mount2.jpg

http://www.tomhoppe.com/misc_pics/seat_mount3.jpg

http://www.tomhoppe.com/misc_pics/seat_mount4.jpg

-Tom

[DavidM]

That's how I'm planning on doing the seat mount in the new body. Have it part of the cage. You can have it touch the floor all you want, you just can't weld it to the floor. Same as the downtubes that will be touching the floor with plates on the bottom to serve as jacking points. :cool:

David

[lateapex911]

That's how I'm planning on doing the seat mount in the new body. Have it part of the cage. You can have it touch the floor all you want, you just can't weld it to the floor. Same as the downtubes that will be touching the floor with plates on the bottom to serve as jacking points. :cool:

David
Position those plates over drain holes if you can, and build a "curved top" insert for your jack pad. Project a bolt through the insert sicking up, and drill a hole in your plate, and your jack now registers with the car, eliminating the car slipping off the jack when the jack is resistant to rolling on less than perfectly clean flat floors.

[Gibson]

'There has been a few instances of a roundy round hornet flipping on its side, drivers side down, and being T boned. Never ends well'

I started out in racing helping a friend build and race a dirt track car, that is where I noticed the soft underbelly of these beasts. The floor pan isn't much thicker than the door skin, imagine getting hit in the door if there were no bars there.

As far as a rule, how about just saying one or two optional bars between the rear hoop and the firewall on the drivers side of the tunnel would be allowed to mount a seat or for driver protection. That is how we did it on the F Prod car I work on now, just ran a couple pieces of tubing from the bottom door bar to the tunnel.