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  • Garagistic roll bar

    I've been thinking about getting a roll bar (rear cage) recently as I track the car 3-5 times/year. I did some research on the VSR one, which everyone seemed to like when it came out, but it looks like it's NLA. What does everyone think about this new offering from Garagistic? It looks good to me, but I'm not sure of what design details to look for.
    https://store.garagistic.com/e30-coupe-bolt-in-roll-bar
    "It is needless to say that self-propelling vehicles, like other machines, will never do as much for one who does not understand them as for one who does."

  • #2
    I have been using the VSR one for years, and that garagistic bar looks identical to it....I mean...I can't tell the difference.

    I have been quite satisfied with the VSR bar.

    Comment


    • #3
      There are usually so many compromises with a bolt in roll bar the parameter that it looks good is probably equal to if would actually save you in a worst case roll over scenario.
      jimmy p.
      87 E30 M3 Prodrive British Touring Car
      88 E30 M3 Zinnoberot - Street
      88 E30 M3 Lachsilber - Race (#98 SCCA SPU)
      92 E30 M Technic Cabrio - S14 POWERED!
      98 318Ti M44, Base - Morea Green
      04 Ford F350 - V10

      Comment


      • #4
        Ive always been curious about bolt in cages. What exactly are the significant downfalls of a bolt in cage? Is it that they do not have plates welded to the floors and likely the cage would puncture straight through the floor in a roll over? Could you just weld in plates to the floor and weld the bolt in cage to the plates?

        I know some cages have bolts going through the cage to assemble it. This one appears to be one piece. So I would imagine, if its welded to plates on the floor, it would be exactly a weld in cage?

        Just looking for info for future reference.

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        • #5
          These 4 point bars are not a cage though. Other than look racey the only thing these 4 point roll bars offer is a bit of B pillar roll protection which is probably the stronger of the A & B pillars.
          In my view these really offer no value other than looks at cars and coffee.

          The value of a real 6-8-10-10+ point welded cage is when you weld it to the chassis in a manner that the pickup points and the design of the cage stiffens the car "and" also provides roll protection. Depending on your rules you can also stitch along the tubes to the A & B pillars, the roofline, etc. The Gruppe A cages are like that.
          A super stiff suspension in a car will end up being greatly diminished if its pushing against a chassis that has the stiffness of saltwater taffy.

          Bolt in "cages"as in 6-8 point type have some of the advantages of the weld in cage, but cannot compare to a welded structure. There were some pics floating around of a European mfg Gruppe N legal cage that actually looked pretty decent.

          Trivia - Our E30M3s because they truly are homologation special cars actually do have a few additional bolting points for bolt in Gruppe N cages that help tie the cage to the chassis a bit better than just the floor plates.
          If you look behind the A and B pillar interior trim you will find some 10mm threaded inserts that were made for the Gruppe N chassis to tie the Gruppe N cages into the A & B pillars.
          I used those on my first 6 point cage on the A&B pillars by adding tabs to the A & B pillar tubes (credit to Don Fields for showing me that 20 years ago). Thats a pretty cool detail the ///M engineers put in.


          Last edited by jimmy p.; 11-17-2017, 05:40 AM.
          jimmy p.
          87 E30 M3 Prodrive British Touring Car
          88 E30 M3 Zinnoberot - Street
          88 E30 M3 Lachsilber - Race (#98 SCCA SPU)
          92 E30 M Technic Cabrio - S14 POWERED!
          98 318Ti M44, Base - Morea Green
          04 Ford F350 - V10

          Comment


          • #6
            I understand that it's not a replacement for a proper cage, and I don't expect it to be. However, I find it hard to believe that it really has no function beyond aesthetics. Any by "looks good" I was not referring to aesthetics, but to the design and layout of the tubes, because that's all you can tell from the pictures. I recall a post here many many years ago when the VSR roll bar came out, where someone installed it and said the first time the took the car out after install, they almost drove the car into the apex of the turn of a familiar back road because the car turned in so much more sharply. That review has stuck in my head all these years. It may have been exaggerated, but it can't be 100% imagination.

            As for bolted floor plates vs. welded floor plates, it's all about surface area and where the plates are located. Given the same location and footprint, a welded and bolted foot plate should have the same "push through" resistance.

            Now what I'm looking for is improved safety and some extra rigidity for HPDE. My car has all original panels and paint (except for CF hood), full interior, and has about 120k miles. I'm very very unlikely to gut and cage it, even though it's a 90% HPDE car and I'll never sell it. If I can get 5-pt harnesses, roll protection, some side impact protection, and maybe some chassis stiffness as a bonus without ripping apart my car, it sounds like a reasonable trade off. Am I way off base here?
            "It is needless to say that self-propelling vehicles, like other machines, will never do as much for one who does not understand them as for one who does."

            Comment


            • #7
              I too think it is not really accurate to say a 4-point bar...bolted in or welded....has no value other than looks. The 4-point bar would not offer the same chassis stiffness nor crash protection as a proper multi-point cage to be sure...but it is not intended to. A 4-point bar would certainly provide useful protection from roof collapse in a roll over crash, and it also provides a solid mounting point for the shoulder straps of a 5 or 6 point harness. Basically it serves the same functions a full cage provides, just not to the same extent. Saying it is useless is similar to saying that a three point seat belt is useless just because it will not restrain the driver as well as a properly installed 6-point harness. Even a simple lap belt, while inadequate by today's standards....is far better than no restraint at all. Same with the 4 point roll bar.

              As far as bolt in vs weld in....I can only speak of the VSR bar as it is the only one I have experience with. As Alpine said....it would be no more likely to tear through the car's body than a weld in bar using the same size mounting plate. The VSR bar also has a "backing" plate so that the bolts cannot tear through the car's chassis sheet metal from below. If installed properly using the backing plate and with high-strength hardware, I would wager a bolted in VSR bar is as strong or stronger than most welded bars. Certainly "strong enough". A grade 10.9/12.9 M12 bolt is certainly more of a known quantity strength wise than your standard mild steel chassis MIG weld.

              If you did the math...three M12 grade 12.9 bolts (which each mounting plate of the VSR bar uses) would require an absolutely insane load to approach failure....
              Last edited by Ironhead; 11-18-2017, 05:08 PM.

              Comment


              • #8
                I did say it offers additional roll over protection to the B Pillar,, but I can't see it providing much if any additional torsional / handling benefits.
                You bolt the main hoop plate to the floor at the B Pillar, then the rear bars bolt through the wheel well. It does not pick up the rear subframe, nor even the rear shock mounts or diff or any combination of those that actually act on the suspension. It just bolts to the sheet metal of the wheel well.
                Yeah there could be a modicum of torsional stiffness acquired through the chassis of the wheel well to the B Pillar but I'm not seeing it being significant enough to say its going to make the car handle better. I firmly, fully, 100% believe the guy who said it made his car get to the apex was 100% a placebo effect. Maybe his additional confidence in having a roll over structure made him actually turn the car in that much harder but I can see it being effective. Just look at the structure. There are no triangulations The only attachment points are the plates at 90į angles to the tubes. Even if there were diags / X bracing inside the rear down tubes to the wheel wells, there are very little forces coming up through the wheel well sheet metal that benefit handling transferring through the leading edge of the wheel wells.

                Sorry fellas, I am trying to be objective, and I do not want to be negative nancy,,, but just don't see any benefit other than a modicum of additional roll over protection, and the A pillar is still the more likely to collapse anyway if the unfortunate happens and the car rolls hard (vs. a soft roll)
                Just my 0.02
                I do like the discussion though.
                Cheers
                jimmy
                jimmy p.
                87 E30 M3 Prodrive British Touring Car
                88 E30 M3 Zinnoberot - Street
                88 E30 M3 Lachsilber - Race (#98 SCCA SPU)
                92 E30 M Technic Cabrio - S14 POWERED!
                98 318Ti M44, Base - Morea Green
                04 Ford F350 - V10

                Comment


                • #9
                  Iíll weigh in with my experiences.

                  After I cut my teeth tracking my m3 I decided to build a 318is/s50 and had a great time tracking it. Once I was regularly hitting 130mph+ on the track I stepped up safety. I put in a VSR 4 pt rollbar and it provided a number of benefits. Firstly ó the chassis did become mildly more responsive, nothing groundbreaking, but stiffer to an extent for sure.

                  Also consider that a majority of accidents donít end in rollover. You can oversteer into a wall, lose your brakes and go head on through a corner into a track out wall or there are many other scenarios. Essentially, of the 100+ track events Iíve done a car is wrecked at every one of them. Iíve only seen a rollover maybe twice, once for sure.

                  Consider the safety a 4pt bolt in can provide solely from a harness anchor perspective in almost any type of impact. Properly secured harnesses on a crossbar right behind the drivers seat is probably a lot better than most other setups. I started using a HANS and proper harnesses and fortunately never had to test them but after I sold the car it went into a wall and the driver was unharmed. Got fixed, hit a wall again, no injuries.

                  Proper cage or 4pt bolt in, at least you have a stable harness anchor point for your shoulder straps and for the $500 a 4pt typically costs I see nothing wrong with that.

                  On a side note my current race car came to me with a safety devices 8 pt cage. Although itís designed as a bolt in, previous owner had a fab shop weld it in. Not my first choice but it passed SCCA scrutineering and is somewhat popular in Europe. It may not be a killer custom cage but seems to be accepted as a safe and compliant option.

                  Dave

                  Comment


                  • #10
                    Originally posted by 1990m3 View Post
                    Proper cage or 4pt bolt in, at least you have a stable harness anchor point for your shoulder straps and for the $500 a 4pt typically costs I see nothing wrong with that.
                    I am in complete agreement with this part. It does give a good solid mounting point for harnesses and I did not mention that in my posts
                    jimmy p.
                    87 E30 M3 Prodrive British Touring Car
                    88 E30 M3 Zinnoberot - Street
                    88 E30 M3 Lachsilber - Race (#98 SCCA SPU)
                    92 E30 M Technic Cabrio - S14 POWERED!
                    98 318Ti M44, Base - Morea Green
                    04 Ford F350 - V10

                    Comment

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