I quickly installed the Hard Dog door bars this morning. I thought the picks of the fitment on their site sucked *** so I thought I would post these as an aid for others who might be trying to decide if they wanted to add them. They tie in to the lower rollbar mount so adding them is quick. They are much less intrusive than I thought they would be.
















On the passenger side I had to move the harness protection tube and switch the mounting tab to the right hand side of it. I still used the same stud to hold it down.

 

They should put that last pic up on their site.

Thanks for sharing.

 

How's the car feel now? Is there a marked difference in stiffness? What about NVH?

 

I wanted these, and I bought them. I have yet to put them in, but I "test fitted" them in my car. Looks like a pain in the nuts to get in and out of, but that's a sacrifice I'm willing to make for added stiffness/ safety. Someday I will put them in. Nice photos! What year is your car/ what roll bar do you have?
Mine is a '99 with a Harddog Xtreme roll bar.

 

Hah! Try getting in/out of a car with door bars designed for side-impact.

Sixshooter - how hard was it to drill through the floor for the bolts for the front mount?

 

Interesting, so they turn on of the bolts into a welded stud and weld the tube over it? Just don't damage the threads on that one bolt I guess.

 

I climbed in and out of the car on both sides but did not drive it yet. I don't predict any change in NVH but chassis stiffness should increase. I already have Stein's stainless frame rails which helped as well.

I have the Hard Dog M2 Sport DD with their padding/cover kit and my car is a '96. This bar provides no noticeable impediment to ingress and egress, which is one of the reasons why I wanted to post the pictures. I predicted it would be much more difficult when looking at the pictures on the Bethania Garage website.

I would have actually preferred them to be about two or three inches higher at the front to make me feel a bit more secure about side impacts but then people with manual windows would likely have interference with their hand cranks. The front bumper height of a stock F-250 is roughly even with the outside door handle so make sure you get hit by a PT Cruiser.

This. A Spec Miata race cage is hard to get into. These are not even a nuisance. I am really pleased to say that they really are no difference to me.

That's the only real problem I had. The flooring sheet metal is thin and too easy to drill through. There are multi-layer sections within a few inches of where this bolts in but not right where this bolts in. I am thinking of making a couple of pieces of thin plate to go under the foot and under the backing plate to spread the load a bit wider at the front and tie into the foremost bolt that holds my Stein's frame rail stiffener and a couple of other bolts to spread the load even better for good measure. Hard Dog probably doesn't do it to keep from being too intrusive but let's face it, the Miata is a sheet metal car and there isn't much structure to it to work with unless you are in the front or rear subframe areas anyway. Even the framerails are a joke. That is why it needs these bars in the first place.







I thought the same thing after I broke one of the grade eight bolts with my "Earthquake" impact gun set on #2 of 6 settings. I'm glad it wasn't a stud. I should be more careful.

 

I am 99.9% confident that Sixshooter will be reporting a big difference in chassis stiffness based on my own experience with the same door bars. It is a bigger improvement than frame rail braces, and a much bigger improvement than a hard top.

Also +1 on egress not degrading much. I had a set on my DD and they did not bother me, definitely not to the point of wanting to take them back out.

 

You've got me wanting to go home and drive it. I can't wait for Road Atlanta, my next track day, to see what differences I can feel.

 

What seats are you using? When I test-fitted my door bars in my car (2001 w/leather seats), they were extremely tight. I made a 1/8" spacer for the front inside two bolts to rock the bar over closer to the door. The bar made slight contact with the door when closed, and significant contact with the seat (read: side bolster was significantly compressed and seat was a pita to re-isntall). Ingress/Egress didn't bother me, but my wife hated them, so I sold them.

 

I really enjoy my hard dog door bars too.

 

I have the Kirkeys that are pictured. There are several inches of free space on either side of them and plenty of room between them and the bars. It isn't an issue.

 

I had the Boss Frog version in the black car before I put the '90 together. They bothered me for DD but did stiffen things a lot. On that car I had a full butterfly, door bars and frog arms. I put the car up on jackstands once (pinch welds). I was off on tooth on one corner and the car tripoded about the length of the errant jackstand tooth. The car was STIFF for an open top.

 

Thanks for the pics.

I never understood the front mounting. Turning down and bolting to the floor always seemed silly compared to going forward and tying in up higher. Then I tried to figure out how to do it and Hard Dog's solution made sense.

Still, a straight bar between the rear bulkhead and the front frame rail seems like the thing.

 

Bolting to the floor makes it easy to install for your average DIY'er. Blackbird Fabworx 6 point bar uses the rocker panels which are quite a bit stiffer but you'll need to weld a plate first to accept the bars.

 

So I sense the biggest reason people shy away from door bars is the inconvenience of getting in and out on a daily driver.
Well what if you could easily remove the bars for daily driving and keeping the SO happy. Put them back in for track days, autocross, etc. but be able to remove them when you don't plan on driving spirited.
I'll get better pics in the day light tomorrow.

 

Not sure that bolt in shear is going to have the same sort of stiffness you'd get out of a seamless tube...

 

The joint is solid, so the only shear is if you were pulling the connection apart. Most of the force will be pushing the jouint together and it it is solid steel with no stress to the bolt. Point is, do you know how much force is being applied and what it would take to shear the bolt? Stronger is not always better. The bolt is near 2000lb shear.

 

So rod stock welded in to each tube end and then milled or cut to get that 90 degree shelf? I haven't seen any empirical studies nor have I done FEA of a miata unibody, but I would be surprised if the loading on that was purely in compression.

Also, I believe if you'd like to sell something on this forum commercially, you must pay to become a supporting vendor.

 

Just saw this. There are two distinct hazards here you should be aware of.

1. You have added a hard and immoveable surface next to your hip. In a side impact, that bar will crush it (your hip). Door bars should only be used with a race seat that has a high padded bolster between you and the bar. Put race seats in it stat.

2. Pool noodles are not "padding". Use SFI rated roll bar padding, which is something like 10x stiffer than pool noodle. Your body mass will blow through that "padding" in a millisecond and not dissipate any appreciable energy in an impact.

You have made your car much less safe for driver and passenger. While sheet aluminum seats are popular, they are not particularly safe unless tied into a full cage in at least 6 spots. Of course no one does that. Stick with an FIA 8855 rated composite seat.

Pls do over. Don't die.