With and without (ChrisC gets a cage)

Brad Roberts · 09-07-2002, 12:25 AM

Chris Cambell bit the bullet and drove up from SmellA to have us do a cage for him today. The car arrived around 4:30 pm. We started removing doors and dash pieces. Tube bending started at 6:30 PM. We are tired.. and I just fired off the 3.2 car after receiving the clutch today.

We will finish the X brace in the doors tomorrow morning and cut the dash back in around the cage. Chris can then drive back to LA. Should be all done by 3PM or so.

B

SummerSledSix · 09-07-2002, 05:45 AM

Brad, what kind of cuts do you make to the dash?

Brad Roberts · 09-07-2002, 03:06 PM

I'll show you in about 1 hour.

We are cutting it in right now.

B

Brad Roberts · 09-07-2002, 07:31 PM

Sorry, forgot to post back after I took the pics.

I HATE having the tube that runs from A pillar to A pillar in front of the bottom dash pad righ in front of my knees (I'm over 6'1)

Well.. to get this under the dash pad requires me to remove the dash pieces and cut them in after the cage has been welded in.

I grew up around full tube chassis Pro street drag cars that had full interiors installed over and around the tube chassis.

So.. I took the cages farther forward into the dash which in turn makes the X opening larger (easier to get in out of the car with the larger X) and moves the knee bar under the stock steel dash.

NEXT. These are fun, and the first time they drive their car with the cage.. they are blown away at how much stronger the car feels.

B

Brad Roberts · 09-07-2002, 07:34 PM

Oh.. the little plastic vent is about 1 inch in front of the A pillar bar. I chop off the back of them and just mount the face into the lower dash pad holes. Looks really clean and stock. When looking at the car from a standing position, you cant see the lower knee bar. The A pillar bars just disapear into the top dash pad.

B

SummerSledSix · 09-08-2002, 03:55 AM

Nice touch!

campbellcj · 09-08-2002, 11:46 AM

Quote:

Originally posted by Brad Roberts
the first time they drive their car with the cage.. they are blown away at how much stronger the car feels.

YUP, I could feel it just driving down the freeway. More of a sharp "thwack" vs. a "creak-groan-kerchunk" over expansion joints.

You can tell the suspension is working more/harder too, because the chassis isn't flexing nearly as much.

I'm stoked

thanks B (and the "behind the scenes" guys who do the real work...ah, just kidding)

Brad Roberts · 09-08-2002, 11:50 AM

No shame to my game:

Find the young guy's who know what they are doing and let them rip.

Chris, we are in management, we *shouldnt* have to bend a tube or sweep the floors.

B

Jeroen · 09-08-2002, 01:08 PM

Hey Chris,

Good to see your car get a cage.
(that was a fast move BTW)

I was just wondering the other day, that you don't see the diagonal brace through the passenger compartment as much anymore...
And behold, what do I see in Chris' car 8^)

How much difference does this brace make?

Cheers,

Jeroen

campbellcj · 02:15 PM

I have been told that the "Petty Bar" (diagonal) makes a huge difference.

It is a pretty major leap for a car that is routinely street-driven. Not a great idea in that application.

Mine won't be street driven much at all, except to-from the track until I get a trailer rig, so I went ahead and did it.

The way this cage is designed/built, I am surprisingly comfortable in the car and the tubes are farther away from my 'space' than I thought. It doesn't feel claustrophobic to me as I figured it might. Even getting in & out has not been a problem (I am not a really big guy though), with the high "X-brace" race version door beams -- the street version has a much lower "Y" type of door bar.

I expected to have serious probs getting in and out without a removable steering wheel, but that wasn't the case either.

This is exactly why I made the road trip to a guy/shop who has done so many 914 cages before. All the tricky crap is "worked out" by now.

I need to POR-15 the floors and cage, pad the bars, and wire up a couple of aux gauges. Then I will re-skin the dash and install some simple "RSR" door panels. That will wrap up the interior for now; then on to the remaining race prep (suspension, mostly) in October.

Brad Roberts · 09-08-2002, 02:38 PM

Jeroen,

SCCA requires a petty bar going forward IF you dont have bars going backwards from the main hoop.

The other cars are either street cars or the interiors where not far enough long to install that bar.

I knew Chris was'nt going to be around for us to install the petty bar at later date....so you see it now.

B

Jeroen · 09-08-2002, 02:52 PM

stoopid me forgot that the cage isn't tied to the front or rear shock-tops...

thanks for clearing that up!

Cheers,

Jeroen

campbellcj · 09-08-2002, 03:43 PM

No thru-firewall tubes at this time.

They may get added later ("version 2.0") if/when the car gets significantly more power & grip.

URY914 · URY914's Garage

Brad,
What size tubing is that 1 1/2"?
What is the wall thickness?

Thanks
Paul

Brad Roberts · 09-08-2002, 06:13 PM

We use inch and a half.

Chris' plans call for a big 6 one day..so.. we went with .125 wall

In a 4cyl car we can legally get away with inch and a half .095

SCCA says cars under 2100lbs (I could be off by a 100lbs) can use .095 wall while cars that weigh more than this need to have .125 wall (production rules) GT rules are different, but this cage fits the GT rules also.

So... 6 sixes lightened up could meet the 2100lb rule, but we dont take the chance.

Plan ahead and make life easier for the owner of our cages.

I have stood in the scrutineers tent at Mid Ohio and had a cage gigged by them after traveling 1200miles to get there. I vowed never to let that happen again (that was 1994)

B

SummerSledSix · 09-09-2002, 04:13 AM

Brad, when you do tie a cage into the suspension mounts, where do you terminate the tubing, and do you reinforce the mounting area in any way first?

I can see that a Petty bar would really jack up the torsional rigidity of the chassis, but I assume there's no way a passenger (uh, make that instructor) will fit in the car anymore, right?

Dave at Pelican Parts · Dave at Pelican Parts's Garage

Since I've seen a couple of them go in, now, and have seen a couple more already installed, I can answer at least part of that.

There are pretty beefy scab plates welded to the top of the longitudinal. (Perhaps 9" long, and the width of the long.) The tubes are welded to those.

And I've never seen a safety steward that wouldn't have kittens if they saw someone riding in the passenger's seat of a car with a Petty bar...

--DD

Jeroen · 09-09-2002, 06:14 AM

Per FIA regulations (that's what we're supposed use over here) the scab plates should be at least 3mm thick at the feet of the main hoops

IIRC, the ties to the front / rear suspension pick-ups should have scab plates at least 2/3 of that (ie 2mm), but 3mm is preferred

The scab plates also have a minimum surface area (which I don't know from the top of my head)

Dunno about the SCCA-rules. You should be able to find this (and more cage building requirements) in the rule-book

Cheers,

Jeroen

Doug M · 09-09-2002, 09:30 AM

Brad, when you weld in a gage do you put it on stands or leave it on the ground?
Doug

maf 914 · 09-09-2002, 10:12 AM

Brad,

Nice work with the cages. Thanks for posting the pictures so we can all enjoy them. I was just browsing the Gunnar Racing site and checking out their project cars which are very nice. They have two 914 projects, one underway and one in the completed project archives that have roll cages. These are open roadsters so they are different from your cages, but you might find them to be interesting. Check it out in Projects at http://www.gunnarracing.com/

Mike