Roll bar + harness for occasional track use?

[FredK]

OK, I see what you're talking about. The VSR and Garagistic bars have the main hoop mount to the outermost part of the horizontal portion of the floor, whereas the Kirk is inboard by easily 4" on each side, bolting to the thinnest, least structural part of the E30's floor. That's pretty aggravating.

I wonder why the rear stays on the Garagistic bar are bent? Also, it simply doesn't make much sense to me that they're using .120 4130, when the primary reason why people go chromoly is to save weight because it's significantly stronger than DOM, and you can get by with smaller diameter tubing.

[amcp]

From the pics Ive seen the Garagistic bar mounts to the rocker area.
I think it was an oversight on Kirks part. Their reasoning was the fuel lines under the drivers side were in the way.
And thats exactly what I plan on doing Fred. Weld plates in.

[FredK]

There aren't any bolt-in rollbars that mount to or tie into the rocker panels. If you are worried about punching through, the best course of action is to weld in reinforcement plates that tie the floor into the rocker panel. It isn't too hard to weld plates like these in, and for peace of mind, it might be worth it.

The racing / HPDE accidents that I've seen involved going off and not rolling over. I think a bigger concern is the lack of front crash structure on an E30, where your legs are probably more in danger than your noggin being crushed by a rollover. It certainly depends on the race track, as sometimes the going gets really rough when you have an off.

[amcp]

I know its not scientific, but heres what the roof structure will do.

https://www.youtube.com/watch?v=_9fw9nou_G8

And Im not saying you need a rollbar or cage for a DE. I'm saying if youre buying either, you'd want one that mounts correctly.

[mindspin311]

You might be right, its better than nothing. But why half ass it? Theres no way the floopan can take the weight of the car resting on it without punching through it, even with backing plates.
And I know that a floorpan isnt where you mount a rollbar or cage.

There's still the roof structure.

I wouldn't call it half-assed. If you dont want a full caged track car. And realistically, a fully caged car shouldnt be a requirement of a DE car. Then the roll bar definitely increases your odds in the event you happen to roll over at a DE. Which you shouldn't ever be doing. Because it's a DE.

[amcp]

You might be right, its better than nothing. But why half ass it? Theres no way the floopan can take the weight of the car resting on it without punching through it, even with backing plates.
And I know that a floorpan isnt where you mount a rollbar or cage.

[Digitalwave]

Don't all 4 pt bolt in roll bars mount to the floor?

[mindspin311]

Yeah, no. Had I known the Kirk roll bar mounts to the floorpan I'd have never bought it. It should have been made to mount to the inner rails, not the rear footwell area.

It's better than nothing. Are you informed of the strength of an E30 floor?

[amcp]

You can buy a Kirk 4pt bolt in bar. Run a 6pt harness. And, keep your factory belts. But I wouldn't touch a seat that's been involved in an accident.

Yeah, no. Had I known the Kirk roll bar mounts to the floorpan I'd have never bought it. It should have been made to mount to the inner rails, not the rear footwell area.

[TobyB]

A HANS or similar only works with a 5/6 point harness.

Or something similar with vertical torso straps.

t

[hoveringuy]

TobyB, Sorry to hear, and to that's a great reminder.

Is HANS only for harnesses or does it work with 3 point?
I have 3-point w/airbag.

[TobyB]

I wrecked once without a HANS.

That was 2006.

I still can't look over my left shoulder.

I wish I hadn't learned the hard way.

t

[Ryan...]

^^ Good link, thanks!

[Digitalwave]

https://www.r3vlimited.com/board/showthread.php?t=201326&page=4

^ Pages 4/5 of that thread are pertinent to your questions.

[e30davie]

Years ago we had a harness bar in an ae86 that went between the two rear shock towers. AE86 rear seat folds down so you can just flip the seats down and put the harnensses on. allowed a harness bar without a rollbar. and the straps were at an acceptable angle. w

Unsure if such a thing would suit e30, shock towers might be alot further back.