Jump to content
Greg G.

Techinical Bulletin--ST/TT B-pillar Cage Notching 3-12-18

Recommended Posts

Greg G.

TECHNICAL BULLETIN 3-12-18

B-pillar Notching for Cage Placement

 

ST1-4

6.2.1 Chassis and Body Modifications to Production Vehicles

1h) "B" pillars of the unibody may be notched to accommodate the placement of roll cage door bars provided that the notched area is welded to the bar(s) that intrude into the B-pillar.

 

ST56.1.3.2 Chassis and Body Modifications

1h) "B" pillars of the unibody may be notched to accommodate the placement of roll cage door bars provided that the notched area is welded to the bar(s) that intrude into the B-pillar.

Share this post


Link to post
Share on other sites
Fair

Thanks for this clarification/change. This allowance really helped us cage a 4 door EVO X. This was for a customer's TT car that needed to go to ST.

35659875_10102889487810189_7364518781080

This car came in with a welded 4 point roll bar, but the top was shorter than the roof (and his helmet), and it was pretty narrow - several inches inside the B-pillar. We cut all of that out and skinned the roof for a carbon panel, too.

DSCN0921-M.jpg

We made the main hoop to where it almost touched the roof skin (3" taller) and moved the seat back, as well as the hoop. We made it about 6" wider than the old 4-point's main hoop that came out as well. That added some protection laterally.

B61G1201-M.jpg

With the main hoop and rear structure in place it was obvious that the factory B-pillars would be in the way of the upper door bars.

B61G1289-M.jpg

With the doors gutted and the door bars kicked out to the door skin, we had over a foot of room from the door bars to the driver.

DSCN1283-S.jpgDSCN1282-S.jpg

But there was no way to get the upper door bar to the main hoop without notching the B-pillar. If we went around the B-pillar then the rear door hinges wouldn't fit, and opeing the back doors (to access cool suit cooler, ballast, etc) was a LOT more work.

DSCN1442-M.jpg

We ended up using two lower door bars - one that terminates on the B (see above) and another lower bar (see below) that slides inside it, at the floor (not near his body).

DSCN1628-M.jpg

This is how the "ladder" structure of the door bars went together on both sides, giving the driver ample "crush" space and snaking around the B-pillar underneath. Just the bar up by his elbow & arm he needed the "notched" routing through the B.

B61G3383-M.jpg

The B-pillar notch was welded to the cage, of course. And we got NASA approvals at every step of this cage build, including the change to the CCR listed.

B61G3798-M.jpg

In the end the customer was happy, the tech inspector was happy, the rear doors could open and close normally, and the car was much safer than before.

Thanks,

  • Like 1

Share this post


Link to post
Share on other sites
Greg G.

Very clean build!  Must be nice having that much room in there for the driver. 

New Forums are great with the easy photos uploads, too!

  • Like 1

Share this post


Link to post
Share on other sites
TurboShortBus

Ah, yes...a textbook example of how to turn a 7 month old tech bulletin update into a watermarked shop plug / build thread.

Mark

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×