One of the mods I have been toying with for a while is a roll bar for my E36. I have heard of roll bars helping with the stiffness of a car (therefore helping with car haandling, etc), but nothing specific about the E36.

I ask the question because adding a 30 lb+ roll bar to the car goes against my current mod, weight reduction. I would like to do some DE's in the future, but the car will see mainly auto-x duty for the foreseeable future. So is a roll bar on an E36 worth it for auto-x?

nope, not worth it for autox

not a bad idea for DEs though.

and its not like it will ruin you for SM


One of the mods I have been toying with for a while is a roll bar for my E36. I have heard of roll bars helping with the stiffness of a car (therefore helping with car haandling, etc), but nothing specific about the E36.

I ask the question because adding a 30 lb+ roll bar to the car goes against my current mod, weight reduction. I would like to do some DE's in the future, but the car will see mainly auto-x duty for the foreseeable future. So is a roll bar on an E36 worth it for auto-x?

i have a cage i say if you want it do it, my e30 is not as stiff as your e36 but it was night and day as stiffness goes

One of the mods I have been toying with for a while is a roll bar for my E36. I have heard of roll bars helping with the stiffness of a car (therefore helping with car haandling, etc), but nothing specific about the E36.

I ask the question because adding a 30 lb+ roll bar to the car goes against my current mod, weight reduction. I would like to do some DE's in the future, but the car will see mainly auto-x duty for the foreseeable future. So is a roll bar on an E36 worth it for auto-x?
James,

I'm not an autocrosser, but for DE events, a roll bar is almost critical.
One, having a roll bar and either 5- or 6-point harnesses is a huge safety factor (and nicer for your instructor).
Two, with harnesses to hold your body in place, you can concentrate on steering input smoothness rather than using the steering wheel to keep your butt in the seat. Both driving pleasure and driving skills improve.
And three, the roll bar will add stiffness to the chassis. How much that stiffness helped me I'm not sure. When I installed mine, the driver was still the limiting factor that determined how well my car handled- I hadn't reached the chassis' limit.

If you do go to DEs (I highly recommend one just for improving street driving skills), you have a great BMWCCA chapter up there with the Tidewater Chapter- I've had a couple of their members as my instructors at VIR.

Sam Lamson

It's "worth it" when you're upside down going 50 MPH. A roll bar is kinda like shingles. You don't need them on sunny days.

I installed a roll bar over the winter for DE purposes but I do a lot of auto-xing also. I have not seen a hinder in performance due to the weight. Actually, since I replaced my vaders with race seats at the same time I doubt I even gained a pound. I have the National tour coming up in 2 weeks and that will be a good test.

if you're going to de it, by all means put one in. if it's a dedicated autocross car, however, you'd be better off saving the weight.

If you are going to be serious about autox'ing, you only need look at the grid at a Nat event to notice that no top runner in an E36 in SM will have a roll bar. Everyone has harness bars since you can make them for ~5lbs.

However I'd not go onto a track without a full cage personally.

So you really need to decide if you want maximum performance for autox, or safety for track use.

If you are going to be serious about autox'ing, you only need look at the grid at a Nat event to notice that no top runner in an E36 in SM will have a roll bar. Everyone has harness bars since you can make them for ~5lbs.

However I'd not go onto a track without a full cage personally.

So you really need to decide if you want maximum performance for autox, or safety for track use.


better yet, bolt the harness into the rear seatbelt holes for 0lbs!

=)

word

better yet, bolt the harness into the rear seatbelt holes for 0lbs!

=)

The harness bar doubles as a camera mount. Might also want to read this article on the length and angle of shoulder strap mounts:

http://www.schroth.com/produkte/rennsport/pdf/06_Anchorage_evaluation_Shoulder_Belts.pdf

put the camera on the top of the car and do squats at the gym. ;)

Russ...he's talking about a roll bar, not an anti-roll bar. ;)

put the camera on the top of the car and do squats at the gym. ;)

I've generally noted that you don't get very good shots of your steering inputs with a camera on top of your car. And no, opening a sunroof and pointing the camera down doesn't count. :stickoutt

Thanks for all of the input guys! Actually, I am very serious about auto-x. In the past few years I have put some serious time and $$$ into the car, and it has paid off IMO.

About the only thing keeping me from getting even more serious (i.e. more national level events) is my current job (that whole Navy thing about having to go out to sea from time to time :) ..)

I think I may invest in one since I would like to do more DEs in the future and the car has quite a bit of race life left since it is no longer my daily driver. But in the meantime I think I will focus on other mods.

So how much does that Autopower roll bar weigh exactly anyway?

So how much does that Autopower roll bar weigh exactly anyway?

If you decide to do a rollbar, you might as well decide on one that isn't a piece of junk.

There are better options on the market for not much more $$.

Russ...he's talking about a roll bar, not an anti-roll bar. ;)

Duh...what is the wedsite again...www.improveyoureadingcomprension.com

If you decide to do a rollbar, you might as well decide on one that isn't a piece of junk.

There are better options on the market for not much more $$.
OK then....recommendations? Why would you say that, BTW?

HMS Motorsport makes a very nice rollbar for the E36 cars.

Does TC Kline still make their bolt-in roll bar?

OK then....recommendations? Why would you say that, BTW?

Because I've seen Autopower rollbars. The welds looked similiar to something I can do (and I've welded maybe three times) and the backing plates weren't even close to large enough.

Heck, I've seen an Autopower cage punch right through the floor of an ITB VW Rabbit (lightweight) during a low speed roll and I just read about an E30 M3 club racer that had it's bolt-in (not sure of manufacturer) cage punch through the floor during a T-bone. Those were cages with SIX mounting points...you are talking about a rollbar with only 4 points to take the load.

I think there are much better options. As a reference, I had a local cage builder built a custom rollbar for my old 95 M3 street car (bolt-in with LARGE mounting plates on both sides of the sheet metal). He fabricated a removable harness bar that allowed me to continue using the rear for storage and then had it powdercoated gray to match my interior. The price came out to around $700 with installation.

There is a GB going on right now on Kirk rollbars. Check the GB forum.

i have a cage i say if you want it do it, my e30 is not as stiff as your e36 but it was night and day as stiffness goes

who made your cage, how heavy is it and is it welded?

One of the mods I have been toying with for a while is a roll bar for my E36. I have heard of roll bars helping with the stiffness of a car (therefore helping with car haandling, etc), but nothing specific about the E36.

I ask the question because adding a 30 lb+ roll bar to the car goes against my current mod, weight reduction. I would like to do some DE's in the future, but the car will see mainly auto-x duty for the foreseeable future. So is a roll bar on an E36 worth it for auto-x?
If you're doing it strictly for chassis stiffness, I'd stay away from the bolt-together bolt-in bars. I'd suggest getting a custom welded cage built, tying the front strut towers into the structure, all the way back to the rear shock towers and subframe mount. Should also weld the cage to the A-pillars and to the rest of the body of the car - just take a look at the cage that Tri-Point Engineering built into Chris Cox's Nationals winning FP M3. Probably don't need the NASCAR style side intrusion bars, so you can save a little weight there. Naturally, this is going to make your car totally unsuitable for street use.

To do it right, though, you're going to have to do some engineering work. The best cage that I saw for autoxing was designed first by computer, then welded into the car, then they jacked up corners of the car measuring the deflection. They removed and added tubing and braces until they had the structure was the stiffest and lightest that they could get. Of course, this sort of development work isn't cheap...

Jim