- Thread starter
- #21
Mad Hatter
Gotta go Faster
Just thought I would add a update to the roll bar post.. No more funky curves! But will modify again now that we have bought a pair of spare doors to hollow out.
Last edited:
The Mustang Forum for Track & Racing Enthusiasts
Taking your Mustang to an open track/HPDE event for the first time? Do you race competitively? This forum is for you! Log in to remove most ads.
- Welcome to the Ford Mustang forum built for owners of the Mustang GT350, BOSS 302, GT500, and all other S550, S197, SN95, Fox Body and older Mustangs set up for open track days, road racing, and/or autocross. Join our forum, interact with others, share your build, and help us strengthen this community!
MM 6pt roll bar modification planned
- Thread starterMad Hatter
- Start date
This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Grant 302
basic and well known psychic
Ah, better! Using your noggin' to protect your noggin'. I think the other bend was okay...but this will be stronger if you ever need it to be.
- Thread starter
- #23
Mad Hatter
Gotta go Faster
Little by little!!!
- 147
- 60
Better, but just don't get t-boned in the drivers's side or slide sideways into a pillar or end of armco.
I realize your rules are loose, and you want to also cruise the car on the street, but as far as racing safety, you can't have it both ways. You're wheelin faster now and are on track with other w2w racers.
In my humble, safety minded opinion, put a real cage in the car. Make due getting in and out.
You hit the wall at a buck and a quarter and you will probably have the same opinion as I now do.
I enjoy your posts here on this forum and would like to keep it that way.
Just sayin'.
I realize your rules are loose, and you want to also cruise the car on the street, but as far as racing safety, you can't have it both ways. You're wheelin faster now and are on track with other w2w racers.
In my humble, safety minded opinion, put a real cage in the car. Make due getting in and out.
You hit the wall at a buck and a quarter and you will probably have the same opinion as I now do.
I enjoy your posts here on this forum and would like to keep it that way.
Just sayin'.
- Thread starter
- #25
Mad Hatter
Gotta go Faster
True, too true!! When we have the doors ready we will make some upgrades to the cross bar. Thanks!
Bill Pemberton
0ld Ford Automotive Racing Terror
Agree with DocB, especially since we all likezzz U, so get some cross beams in there and cover them with the proper rubberized bar covers. Cool you are getting some hollowed door panels because that will also allow you to build the bars out a bit more for side impact protection. Plus getting rid of some extra weight that has no purpose , so keep us posted on your progress!
Be safe !
Be safe !
So.... wow... the bolt-together erector set "cages" based on a 4-point always make my eye twitch. 
I didn't see the earlier wobbly noodle A-pillar / vertical bars until after they were replaced with straighter bits, which are better. It still makes me wonder - how would this perform in a rollover?
I am not one that advocates for full roll cages to ever be used in street driven cars. Even with SFI padding on the upper door and windshield bars, whacking your bare head on a door cage can do some serious damage to your brain and skull. We stick with 4-point roll bars on street driven cars - period. And for the S197 chassis I feel that Maximum Motorsports makes the best one, as long as you get the optional diagonal and harness bar in the main hoop, as shown above.
The main issue I have with using the street car based 4-point kits and "turning" these into a roll cage is they are made to fit within the confines of interior, so they never use all of the available room inside the chassis. Above is a stripped S197 Mustang where the main hoop of the cage was pushed out to the limits of the chassis, which is inches beyond where the headliner and interior plastics allow. Sometimes we will even cut out some of the inner sheet metal structure to gain even more room away from the driver. That space allows for the cage to crush in a heavy impact, and the more margin we have the safer the driver can be.
A dedicated race car with a fully stripped interior and gutted doors gains you a lot of room between the steel tubing of the cage and the human occupant(s) inside.
This EVO X came in with a street car 4-point roll bar welded in place. It was built for use with the headliner, so when it came time to put in a full cage - we had to cut it out and throw it all away. It was 3" shorter than the main hoop we built for this car. The door bars were a full FOOT away from the driver, once we gutted the doors. Cannot do that on a street car, of course
Cages go hand-in-hand with a seat install. The S197 above had a simple Cobra seat and slider which was somewhat tall. Look where the driver's head is in relation to the roof and upper door bar. We replaced that with a Sparco seat that had head restraints - which don't work for street use but are a huge safety upgrade on a track car. We had a fitting with the customer and mounted the seat lower to give him more headroom - yet the padded upper door bar is still too close for safe use without a helmet.
Anyway, I didn't mean to start some "cage design" tangent, and hope I didn't get too far off topic. I do applaud the OP for at least trying to upgrade his 4-point bar, just know that the MM 4-point kit is made for casual HPDE use and built around the restraints of an interior. It can never provide the level of safety and "crush room" of a proper roll cage pushed to the limits of the chassis inside.
Cheers,
I didn't see the earlier wobbly noodle A-pillar / vertical bars until after they were replaced with straighter bits, which are better. It still makes me wonder - how would this perform in a rollover?
I am not one that advocates for full roll cages to ever be used in street driven cars. Even with SFI padding on the upper door and windshield bars, whacking your bare head on a door cage can do some serious damage to your brain and skull. We stick with 4-point roll bars on street driven cars - period. And for the S197 chassis I feel that Maximum Motorsports makes the best one, as long as you get the optional diagonal and harness bar in the main hoop, as shown above.
The main issue I have with using the street car based 4-point kits and "turning" these into a roll cage is they are made to fit within the confines of interior, so they never use all of the available room inside the chassis. Above is a stripped S197 Mustang where the main hoop of the cage was pushed out to the limits of the chassis, which is inches beyond where the headliner and interior plastics allow. Sometimes we will even cut out some of the inner sheet metal structure to gain even more room away from the driver. That space allows for the cage to crush in a heavy impact, and the more margin we have the safer the driver can be.
A dedicated race car with a fully stripped interior and gutted doors gains you a lot of room between the steel tubing of the cage and the human occupant(s) inside.
This EVO X came in with a street car 4-point roll bar welded in place. It was built for use with the headliner, so when it came time to put in a full cage - we had to cut it out and throw it all away. It was 3" shorter than the main hoop we built for this car. The door bars were a full FOOT away from the driver, once we gutted the doors. Cannot do that on a street car, of course
Cages go hand-in-hand with a seat install. The S197 above had a simple Cobra seat and slider which was somewhat tall. Look where the driver's head is in relation to the roof and upper door bar. We replaced that with a Sparco seat that had head restraints - which don't work for street use but are a huge safety upgrade on a track car. We had a fitting with the customer and mounted the seat lower to give him more headroom - yet the padded upper door bar is still too close for safe use without a helmet.
Anyway, I didn't mean to start some "cage design" tangent, and hope I didn't get too far off topic. I do applaud the OP for at least trying to upgrade his 4-point bar, just know that the MM 4-point kit is made for casual HPDE use and built around the restraints of an interior. It can never provide the level of safety and "crush room" of a proper roll cage pushed to the limits of the chassis inside.
Cheers,
- Thread starter
- #28
Mad Hatter
Gotta go Faster
Its true.... little by little has been the approach. Not ideal, I do realize! The car is still "street" legal (sort of..) and gets to the track on its own steam, having a problem pulling the plug and going all the way but rear seats are out and rarely have the passenger seat installed, and then only for a helmeted mechanic etc). Will be adding cross braces during our off season (Summer months of Jan and Feb.)
No brawling!!! I promise...........
No brawling!!! I promise...........
Grant 302
basic and well known psychic
Timely advice Terry.
Hi Terry,
I'm almost ready for those MCS coilovers for my 2019 GT racecar build we talked about. I'm fabricating my cage right now. I run those bars touching the roof to get all the space I can.
carl
My mainhoop is at the same angle as the "B" piller but flush against the roof where the rollover hoop typically ends in say a Watson racing road race cage. Just about everyone else uses the rear seat shelf as the rollover hoop footing. It does use less metal but has several other issues IMO.
I weld to the high strength steel vertical B piller by plating here then using a hortizontal footing bar to the tunnel which is low strength steel. Then I weld the rollover hoop full height touching the roof and full length within 1.75" of the floor (that helps me temp push the top halo bar to main hoop down to complete my welds). You can see how I use the full cabin width. This take time to be precise. This allows #1 the ability to use the horizontal footing bar as the rear end of my to be welded seat base. I weld a seat base so the car can collaspe around me but my seat is fixed to my cage. This design makes the cage attachment points to the chassis less important. Essentially making the seat part of the cage makes a monocoque within the chassis. That isn't really possible + added more metal integrating the seat base with the Watson racing style main hoop footing.
Second the future crossbar downtube will end at this cage footing node further stiffening the chassis.
Third the angle of the rollover hoop to "B" piller will mate perfectly with my future gusset to the 'B" piller adding even more stiffness to the chassis. That gusset is the 14G steel plate with the holes in it.
Fourth my NASCAR driver's door bars will have the proper emergence profile like an egg crate protecting your eggs. The typical Watson racing door bar design have an additional bend at the door bar to get past the 'B" piller that weakens the door bar setup and their door bar type has no gussetting to the sill plate or sill tube making for an additionally weak structure.
This is proper shape and gussetted IMO. Forces of impact are directed into the A and B piller and supported at the sill plate. I did this for a corvette.
I'm no engineer or pro builder. So that Watson design must be perfectly fine because they do it 100's of times and no deaths. I don't know any better and have few data points so I build with no margin of error. All cage designs are a compromise. Watson is a pro outfit and they do what they do for a reason.
I think I enjoy building cars as much as racing them.
No, you are right to second guess the "floating" door bars and the double S curves on the WR cages - both of which are compromises.
If there isn't a good way to avoid the double-S, tying the door bars into the frame/base of door opening is a good idea and should add a lot of side impact strength (see below).
Avoiding the double S is always a good design. Just requires cutting into the door jambs, but it will be safer.
Make sure to check your class rules / organization's cage regulations. We had tied both sets of NASCAR door bars into the frame on this C4 Corvette...
...and got penalized for it on the passenger side and had to cut those out. As well as the forward firewall bar below.
There is a fine line between adding safety and adding too much rigidity, at least in some classes. Just read the rules and ASK THE TECH GUYS BEFOREHAND instead of asking for asking for forgiveness after.
Anymore I will avoid double S door bends - damn the door jambs.
If there isn't a good way to avoid the double-S, tying the door bars into the frame/base of door opening is a good idea and should add a lot of side impact strength (see below).
Avoiding the double S is always a good design. Just requires cutting into the door jambs, but it will be safer.
Make sure to check your class rules / organization's cage regulations. We had tied both sets of NASCAR door bars into the frame on this C4 Corvette...
...and got penalized for it on the passenger side and had to cut those out. As well as the forward firewall bar below.
There is a fine line between adding safety and adding too much rigidity, at least in some classes. Just read the rules and ASK THE TECH GUYS BEFOREHAND instead of asking for asking for forgiveness after.
Anymore I will avoid double S door bends - damn the door jambs.
I'm doing something new. My 1st racecar I welded X door bars. That was the way back in the day. Then later builds I did NASCAR bars supported at the sill plate like Terry's picture done way into the door innards cut out. My new design for my S550 is 1/2 deep NASCAR bars with 14G gusset welded to the face of the NASCAR bars then the NASCAR IMPAXX 4" thick foam block in the door.. The door will now basically be a crashbox (crash attenuator) ultimately stopped by the gusset face of the NASCAR bars. It will be similar to the crashbox on the corvette C6R but I won't have to step over it since mine will be in my door not on my cage.
TMO Supporting Vendors
