I wonder how it affects the stiffness and support of the rear suspension.

Just finished a 98 Dakota. Owner did not want bars out of rear of cab period. And Yes, the rule says 6" from top of hoop bars have to come down at no less than some angle and be of a certian diameter depending on the length. I even offered to do the bars off the seat brace area of the main hoop through the bed. No, was the answer. I left the door bars out until they finish all the interior work.

You can do a 25.5 SFI funny car cage with all necessary bracing and leave out the rear bars and be legal. They did not want a noticeable cage. I meant to take some pics. Plan to get some one evening this week. I will try to post them.

Not speaking for James but he probably wanted a cage for the same reason these guys did. Just to get the tech guys to let him race at local track. A main hoop is all we needed but I put the A pillors windshield and dash bar in nothcing the steering column and welding the dash bar in. Making the best of what a customer was willing to let me do for them.

James that is a nice fitting, looking, purpose built cage. NHRA may not think so but they will not like the one I just did either. I did not build for NHRA or IHRA. I built for the customer who only wants to run the hillbilly tracks around our house.LOL

Leon

Thanks Leon, that is what I figured. I always appreciate your input.

WOW! Very nicely done! It pays off to do it right!

-Kenny

Thanks guys!

Leon, sounds like your customer was thinking exactly like me (except I did the rear bars like you were suggesting so that I could tie the entire frame together). Is it legal to run 11.50 or quicker? According to every rule book I have seen, no. However, my chassis builder said he has had several of them certified...

But, the main reason was to have some sort of protection, but keep it hidden and hope the track gives me some slack.

I see no reason it would not be good to 10.00. Its more or less a 6 point installed backwards, and it has door bars to protect driver. Not what we are used to seeing but I would say much better than a six point which is good to 10.00.

Very nice James! How do they weld the backside being that close to the roof? Was it installed with the headliner in?

this may be a stupid question but what would you do if you needed to pull the bed off?

I recently moved and can't put my hands on the NHRA rule book. The rule on the upper cage or roll bar supports is pretty simple. It says they have to be rearward and gives a limit on angle. It also states what size you can run if you run 2 bars 4 bars and how long those bars are. Ihave SFI spec 25.1E, 25.2, 25.4 and 25.5. Except for 25.5 these SFI rules have nothing to do with this.

The cage I was building started out just going to be a roll bar. 1.750 .083 Chrome moly is unobtainium. I refuse to do .134 cold roll electric weld mild steel. In fact the customer installed that and I cut it out. I placed a call to Jim Collins SE Div NHRA tech director. He also sits on he SFI board. Asked about a truck that should run faster than 11.49 but would probably never go 9.99. What do I have to do to be legal. He simply said 25.5 or some bars got to come off of main hoop no more than 6" from top specified in the NHRA rule book. Customer refused a funny car cage and X-ed doors. I really had some cool plans and was going to basically give the job away. But, he refused. I was told if I put too much in the truck and someone poked fun about being slow for so much cage he would cut it out. So I gave him exactly what he asked for and nothing else. They are more interested in street use than Dragstrip. The Timeslip is just a bragging right.

The reason for the rear bars is. So that if the vehicle were to roll over and get hit say in the drivers A-pilar the cage would not roll rearwards. This makes perfect sense in a car. But a truck is different. The cage cannot flip rearward without tearing the cab apart. The idea behind 25.5 is the drivers cockpit including the seat mount is tied together. Deleting the requirement for rear bars. If you notice all the SFI specs are drivers compartment only. Are these cages safe. Sure.

Another note... If you bend the rear bars for appearance or head room. They will continue to bend in an accident. Once you bend you weaken the tube. Bends are pretty and comfortable but weak if not properly braced.

Leon

cudarex: yes the headliner was out. They replaced the windshield so the headliner was slid in from the front.

I can't pull the bed, but I don't ever see a need to.

Leon, makes sense about the cab being the support for the main hoop. Maybe they will modify the rule one day. And the main hoop and halo bar have no bends besides the 90's needed to go around the cab.