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rayaapp2

Bad Dog Z Full Length Frame Rails

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Hello folks,

 

Last week after many years of putting this off I finally installed my bad dog z frame rails on my 260z.

 

I thought Id give you all a brief overview of the install for anyone looking to do this on their own. This was an early 260Z with a non-catalyst floor pan.

 

I opted for the full length rails. I bought these back when Bad Dog first started making these full length. I think sometime between 2004 and 2006, I dont really recall.

The front rails are sweet. As long as you have solid straight rails to start with they are pretty painless. I had to do a little beating on the passenger side rail to get the rail to slide over snugly. All the undercoating and paint was removed with many hours of propane torching, chiseling, grinding with a sanding disc, and finally wire wheeling for a good surface. A word of caution though, strip the in cabin floor of tar and paint as well when welding. I stripped the tar off for the most part several years back to patch various rust holes, but forgot to strip the paint off again inside. The inner side of the frame rail towards the transmission tunnel will require special attention while you are welding. The transmission tunnel vinyl and organic matt is very close to where you are welding and can/will catch on fire! I kept a fire extinguisher and a spay bottle with water on hand. I ended up spraying the matte and vinyl down with the water bottle to keep it wet and catching on fire. It started to smolder several times. The only other spot that was difficult was near the inside of the front frame rails against the T/C rod bushings. Take them out before welding. They can catch on fire or melt.

 

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EDIT: Dont forget to remove the rubber floor plugs... I did, just forgot to mention it.

 

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When your fabricating for over 48 hours straight with no sleep, the drink of choice is Monster for us. You can see our "Import" can stickers were just peeled off and placed on the speedo and tach gauges. We started putting them everywhere on the car... lol

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The carpet and seats were removed for this job as well.

 

Once the front rails were in place and placed as far forward as possible near the T/C rods I was able to fit and trim the rear rails for fitment. I will get back to the front frame rails in a moment. The rear rails did not completely fit the floor pan in the valley towards the rear box frame. There was a gap near the top and next to the box frame. The pad that lays on the box frame also had to be modified. It was welded up from bad dog so that it was 90* exactly from the frame rails. The rear box frame had a slight angle in it. so I cut the pad off and cut the rear rail to angle the L pad to fit the box frame on the back. There was still a gap at the top with about 3/8" of clearance that I could do nothing about. If I had more metal around I could have filled it, but it was like 3am by the time we had this figured out and decided that it would be okay to have 2" of gap there and that I could go back later and weld in some filler plates if need be. You might be able to use the rail pieces that you cut off to fill the gap if you really want to get anal about it and dont have any extra metal around. Once the fitment was dealt with we welded it all up. We constantly had issues with thinner rust areas in the floor while welding. This resulted in holes in the floor that had to filled in later.

 

P1050883.jpg

 

Back to the front rails. You will find that if you weld the front rails on full forward and up against the T/C rod plate(where I sometimes jack it up because its extra thick there) that the rails are just straight and that the outside of the original frame rails curve in. I cut a slit on each side several inches back and C-clamped the rails into place and welded them to the original rails. This worked out beautifully.

 

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Over all Im very happy with the results. But Im use to all the difuculties of working on old rusty metal. Do not expect your car to have perfect floor pans no matter how good they look. They were probably pressed out which resulted in thinner spots in some areas and oxidation over time may have taken its toll where you cannot see it from either side. Tack weld them in place with your car leveled out out in the area and supported from strong areas like the front cross member and rear/front diff mount to try and prevent any tweaking of the frame. Once you are tack welded up stitch it together, but dont focus on one area to long. General welding rules apply.

 

 

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Edited by rayaapp2

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Totally worth it in the end. The plastics in the rear use to squeak when I went over speed bumps from the flex(running pretty stiff coils on it) and now they dont make a noise. The car definitely feels more solid while driving down the freeway as well. Although I did install a set of nice seats in the car as well. The seats are not completely worn out like my old ones. I dont know what they are from. A friend happened to have a set he thought were from a Toyota, and they happened to fit the car very well. That could be affecting my perceived solidness as well.

 

Ray

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Ray:

 

Very nicely documented application of Bad Dog rails. Need to do the same to my 240Z except the passenger floor is buckled upward. Same on drivers side but to lesser extent. Need to remove existing frame rails then use portapower to push floors back into position and anchor same with new Bad Dog rails that are on hand. Want to add 90 degree and "C" channel on top side for more strength. Right now it is TOO HOT in Arizona to do much of anything outside.

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Ray,

Well documented and described. I went this route myself with the bad dog rails/sub connectors and new floors from Zedd findings. Man what a difference just climbing into the car. It feels so strong and rigid and barely gives under my weight. Thanks for posting your results...

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Ray:

 

Very nicely documented application of Bad Dog rails. Need to do the same to my 240Z except the passenger floor is buckled upward. Same on drivers side but to lesser extent. Need to remove existing frame rails then use portapower to push floors back into position and anchor same with new Bad Dog rails that are on hand. Want to add 90 degree and "C" channel on top side for more strength. Right now it is TOO HOT in Arizona to do much of anything outside.

 

 

A large rubber mallet(like something you would have seen in Looney Tunes Acme style), and some strong legs is all we had to straighten the passenger side out in mine. I braced myself against the top of the door threshold for short bursts while my buddy welded the pans down to get them perfect. A harbor freight dolly set also comes in handy to get any small bumps out one your done.

 

 

Thanks guys, I dont really have much to offer Hybridz these days so its the least I can do until I can make a donation.

 

 

Ray

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You can buy them from Bad Dog as far as I know. That is where I purchased mine.

bad dog parts

I believe Bad Dog Z is also a member of this board.

 

 

If you are looking to spend less and you have fab skills, you can try your local area for places that sell steel. Have them cut some stock for you and put it together yourself. Just depends on what your time is worth. Personally I do not have a plasma cutter, and the time to measure it all out. It took some time just to prep the car(74 hours between a Wed and Saturday mornings). It would have taken many more hours to fab the rails up as well. Trust me when I say Bad Dog's rails are well worth the time and costs if you are not equipped to build your own rails.

 

You can always keep your eyes open for a set of un-used rails second hand. Ive seen those and the Zedd Finding Floor pans pop up once in a while. Good luck!

 

Ray

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Right now it is TOO HOT in Arizona to do much of anything outside.

 

That's why they put lights in the garage...

 

I would go to sleep around 6pm, right after dinner, then wake up and work on the car from midnight to 6AM, take a shower, have breakfast, then drive to work!

 

Believe it or not, it kept my weight down for some reason.And I got a lot of work done, much to the chagrin of the neighbors at some point or another! :lol:

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Thanks Ray for the info, I guess I will be placing an order for both frame rails. You didnt have any problems with the supplier did you? These people seem to be pretty legite and resonable, I just got the runaround by modern motorsports not to long ago and dont want to get hastled again. Thanks again

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A large rubber mallet(like something you would have seen in Looney Tunes Acme style), and some strong legs is all we had to straighten the passenger side out in mine. I braced myself against the top of the door threshold for short bursts while my buddy welded the pans down to get them perfect. A harbor freight dolly set also comes in handy to get any small bumps out one your done.

 

 

Thanks guys, I dont really have much to offer Hybridz these days so its the least I can do until I can make a donation.

 

 

Ray

I used a short handled 2# sledge hammer with a piece 2x4. It got out the dents from a misplaced floor jack and then I hammer/dollied out the smaller dings like mentioned above.

Thanks for the post about the bad dog install!

Edited by theramz

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Thanks Ray for the info, I guess I will be placing an order for both frame rails. You didnt have any problems with the supplier did you? These people seem to be pretty legite and resonable, I just got the runaround by modern motorsports not to long ago and dont want to get hastled again. Thanks Oiagain

bad dog parts is top notch to deal with. I bought a bunch of stuff from them and I was very pleased with their customer service

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I need to take Tony D's advice and work through the cooler night.

 

Right now there are more aspects to the project and need to tackle them one a time. Need to align the rear of the T56 transmission and R200 rear end to get the angles just right then finish fabing the rear trans mount. Need to remove the existing subframe rails, straighten the floors and weld in the Bad Dog Frame Rails. Suspect the floor pan steel is real thin and needs great care in welding the new Frame Rails. Would also like to weld in "L" channel on the top side to the Bad Dog Sub-frame Rails with a spacing such that I can weld a "C" channel to the two "L" rails on top of the floor to gain much added strength. Likely cleco the whole mess together during the process, then plug weld through the "L" rails through the original floor to the Bad Dog rails. This should allow for a GOOD STRONG weld. Then add the "C" channel on top for added strength.

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That's why they put lights in the garage...

 

I would go to sleep around 6pm, right after dinner, then wake up and work on the car from midnight to 6AM, take a shower, have breakfast, then drive to work!

 

Believe it or not, it kept my weight down for some reason.And I got a lot of work done, much to the chagrin of the neighbors at some point or another!

 

 

Its easier to do this when your young.:)

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