Dan H.

http://dougrippie.com/products/drm-c5-c6-chassis-bar/

I was looking through the DRM site and came across this item. With its price similar to the two available harness bars, it made me wonder if this is an option.

If you are using this, how does it mount to the car? Any drilling or cutting necessary? Or is it a bolt in.

Thank you

LateBreak

People definitely use them as a harness bar, which is a much safer plan than using a harness bar without some kind of added rollover protection. (DisclaimerL They're not sold as a 'roll bar' for insurance reasons I'm sure, but there's certainly some added safety)

(EDIT: See Randy's response below V) along with cutting/notching the carpet to fit around it if you intend to keep the rear carpet in the car.

0Randy@DRM

So I got your email also but figured answering here would work for the mass people. Our bars have always been a weld in part. There really isn't a good way to bolt down any of the 4 spots. Because of the welding it in, you must remove the gas tanks. As my welding teacher always said you don't want a free trip to the moon.

Seat belts wrap around this bar nicely.

Randy

Bill Dearborn

I had a similar style AutoPower roll bar installed in my two C5s. If the welder knows what he is doing they can weld the mounts in without pulling the gas tanks. The issue is the between tank gas crossover tube which runs just below the horizontal cross bar. To weld the rear down bars you will need to cut some holes in the fiberglass tub floor to reach the frame. The holes will be right about where the storage well is located.

When the guy who installed my bar said he was going to do it with the gas lines in place I asked if he was sure and he said, "No Problemo". The car had Comp Insurance and I stayed away from the shop that day. That was 14 years ago and the car is still running and he is still breathing.

Is the bar better than a so called well designed harness bar? Who really knows as few of any of them have been given a true test under crash like conditions to see if they or the mounting points in the car can stand the forces being applied.

As for rollover protection I found out a couple of years after I had my roll bar installed that GM recommends that all roll bars be mounted so the vertical load experienced in a roll over is transferred to the B Pillar or the frame. The thin sheet metal hump behind the seats isn't designed to handle vertical loads and will fail if used that way. I got that information from an email a GM Engineer sent me about mounting roll bars in the cars. Basically, it told me the close to $2K I had spent for the rollbar and installation in two cars was wasted.

The few rollovers I have seen there is little need for a rollbar as the stock roof halo does a fantastic job of supporting the weight of the car. The problem is the A pillars don't do so well and they will collapse pushing the windshield header into the passenger compartment. Since a rollbar is mounted under the roof halo it doesn't provide any added protection from the collapse. The only thing that will stop that is roll cage. I am attaching some pictures of a C6Z that dropped about 4 ft off a tire wall onto its roof that shows the problem. The instructor (a friend) sitting on the passenger side had his head pushed forward and into his chest as the roof pushed upward as he was coming down in the stock restraints. He suffered a spinal compression injury. His body was already as far to the left as it was going to go before the car dropped as his side of the car was upward on the wall so gravity was pulling him toward the driver just before the car dropped off the wall. I witnessed the incident from start to finish and talked to him within a half hour after it occurred so this is just about as accurate of account of what happened that anybody can get.

Bill

0Randy@DRM

I wonder what the GM engineer would say about running a harness bar and a 6 point harness?

Dan H.

Thanks for the feedback guys, and thank you Randy for your prompt response! I'm not ready to start welding things into my car, its a bit further than I'm willing to go right now. For me that would be one of those turning points where I have a track only car...

hklvette

I would guess that they would tell you to go straight to a full cage. Putting in a roll bar doesn't fix the weak A-pillar and lack of a solid link between the top of the A-pillar and the B-pillar.

Bill Dearborn

I bet he would say go with a full cage. His email to me emphasized how weak the cross beam behind the seats was and that it could not stand anywhere near the vertical load the B pillars could withstand. Even this picture shows the halo held up pretty well under a side impact. Here is the email I received with names deleted.
======================================== ===
---------------------- Forwarded by SD /US/GM/GMC on 11/12/2001
02:57 PM ---------------------------


MN
11/09/2001 10:01 AM

To: SD /US/GM/GMC@GM
cc:
Subject: Re: Rollbar for C5 (Document link not converted)

As with any rollbar installation, the attachment points are critical. The loads must be transmitted down to the main rail through significant structure. The lock pillar is significant as it carries the roof bow. However the cross car beam is not load bearing in the direction that an additional rollbar would apply loads. What we usually do is weld a gussetted plate on top of the beam and to the lock pillar for the main roll hoop to weld to. This will transfer loads from the rollbar to the lock pillar to the frame rail.
======================================== =

Bill