47 replies to this topic

[2redrovers]

G'day everyone, I'm currently working on an LH sedan for a customer and as part of the build, I'm making up chassis extensions to bridge the gap between the original rail and the lower rear diff mount. It's been suggested that members of the torana community may be interested in what I have made as an alternative to the bolt on chassis strengthening kit available on the market.

Is this a solution that you would be interested in for your build? My parts are made from 2mm steel, profiled and tailored to hug the floor pan without cutting or intruding into the passenger compartment. Once welded into the vehicle, they become a full box rail with a 2mm plate sandwiched against the original floor to give them the best ability to resist stress loads. My intention is that they will be used in conjunction with full chassis boxing plates but could be used as a stand alone with fish plates at the joins. I've tried to emulate the factory look of the existing rail so that on first glance they don't look out of place.

They are time consuming to produce so I would be mostly making them to order. Price is yet to be determined as I need to cost them out properly but I aim to make it as attractive as possible.

I've added a few in process photos to show you how it all works.

Thanks for your time and feedback

An early shot showing the prototype parts that go on to make up the rail sections.

The parts are shaped and fitted to the floor pan and the diff mount, there would be some adjustment room for you to final trim the join to the original rail ends because as you're probably aware, none of these cars are exactly the same as the next.

This is what the section looks like when it's ready to weld together

That gets done first then the cap can be fitted afterwards. Eventually the end result looks like this. They end up roughly 40mm below the floor level which as far as I can work out, is a reduction in the ground clearance by about 20mm overall.

[myss427]

Looking good, would also tie it into the back half chassis with a 45 degree joiner.

[2redrovers]

Looking good, would also tie it into the back half chassis with a 45 degree joiner.

For this particular build I am boxing the rails fully from the radiator support right through, including the diff mount itself. Plates are being made from 3mm steel to go over the infill sections described here. I definitely agree that you should add some additional fish plates to support the joints if you weren't going to box over the top.

[2redrovers]

Apologies, what you suggested didn't sink in the right way at first. Yes agree with you that a tie in with the rear frame is a good idea too. I've carried out other reinforcing to the structure of the car and waiting for an engineer to give the nod the whole plan. Need to ask about going further rearwards than the diff mount because not all of them like that on a street car (crumple zones and such)

[myss427]

Yes, on mine, I could also not go any further with the strengthening than the front cross member mounts as I would change the crumple zone design. Had to follow the engineers design of the triangulating of the top of the rails to pass my report.

[axistr]

Done the same thing to my hatch 14 years ago. Profiled them the floor, mine are only two piece. I folded a 2mm steel plate into a channel then profiled it to the floor leaving a 2mm gap between the floor and u channel, then welded a 2mm plate the shape of the floor. Then welded the plate to the u channel and spot welded the extensions to the rear control arm mount, floor and existing end of chassis rail. Looks factory and no internal protrusion. The hatch it running 513hp & 503 ft pounds of torque and an 11 1/2" rear tyre foot print. Never had any movement or twist in the chassis, rock solid. I haven't needed any further chassis improvements only the rear extensions, a few more welds on the rear control arm mounts, boxing the control arms and more welds on the k frame mostly around the engine mounts..    

 

 post-393-0-04413000-1447407042.jpg   173.53K   34 downloads

[2redrovers]

Axistr, I like it definitely an effective solution. I know that what I've done isn't a new idea, just a slightly different approach and might be useful to someone if they are looking for a basically ready to install option.

[Big_Red]

What are people doing with the fuel and brake lines? Handbrake cables just going strait over the top?

They look like they have a fair bit of setup involved.

[2redrovers]

These things have taken up so much time to get right. It's one thing to make a one off part to fit the car in front of you, it's a whole other ball game to make parts for someone else to install. Think I might be nuts.

I don't think you'll have trouble with ground clearance unless you're going really really low. From what I can measure there's a difference of only 20mm between the lowest point on the diff mount and the new low on the rail when measuring relative to the pinch seam on the sill/floor join.

As for the brakes etc, no idea just yet. My customer is installing aftermarket front and rear ends so it's likely to need custom built adaptation to make it all work. Might be as simple as removing and replacing the brackets in the same location on top of the new boxing or it could mean something entirely different.

I've seen photos of other people who have done similar mods and it looks like they just run over the top with the cables.

[2redrovers]

Here are the final production extensions, ready to be mailed off to their new owner.

Plug weld holes predrilled so you don't have to. Just trim the rail end to suit your car and start welding them in. If anyone else would like a set, let me know. Price for a set is $550 +postage.

[jeffblanco]

Hi 2redrovers,

do you make one for a LX hatch?

 

Regards Mando.

[2redrovers]

Hi 2redrovers,
do you make one for a LX hatch?

Regards Mando.

Is there a difference in the floor pan between the sedan and hatch? I've worked on both but not at the same time. As far as I knew they used the same profiles and therefore these would fit a hatch as well. Can anyone confirm please?

[myss427]

Same floor on both.

[2redrovers]

Thanks for that, I thought they were same but wasn't sure 👍

[2redrovers]

Installation process. <br />Firstly, ensure both sides of the floor pan are clean and free from original paint and sealer. Apply weld through primer to the area that the extensions will cover. <br /><br />Next, using self tapping screws or similar, attach the baseplate to the floor using some of the predrilled holes. An even spread across the base to keep tensions even and to bring the floor tight against the new parts. Pay close attention to the fitment at each end of the extensions, trim any excess material in order to achieve a neat fit for welding. <br /><br />You can either mig or tig the parts in place, either process is fine so use what you have or are more comfortable with. There is generally no extra benefit for tig in this situation though and may in fact be more difficult to achieve good results with the two different steel thicknesses.<br />Start with the rail join. Solid weld with good penetration, weld inside and out if necessary for a smooth finish. <br /><br />Stitch weld along the inside corners to join the baseplate to the original rail sides. Also run two welds onto the end of the plate connecting it to the floor inside the rail. <br /><br />Start with the four plug welds in the end of the plate. Hot welds with correct wire speed and always start your weld in the center of the holes, on the floor itself, then circle outwards to attain full fusion. The back should look something like this.<br /><br />Space out the first group of welds across the length of the plate. A spacing similar to this is a good idea to keep the heat down and stress to a minimum. Don't be afraid to hammer up the floor from the other side to ensure a close fit.<br /><br />Carry on plug welding slowly, allowing it time to cool naturally as you go without rushing it. Move the screws around as needed to help clamp the parts together for a tight gap. Eventually you will end up with this.<br /><br />The next step is to weld the seam between the plate and the suspension mount but only after the whole thing has cooled down. If you do this last join too soon it could be under stress which will increase the chance of cracking over time.

...

[2redrovers]

This is optional, trace a line from the corner of the mount to the edge, and trim to make it look like the flange is continuous. <br /><br />Unlike other replacement panels, you will have to trim and adjust the ends to suit your car. Be aware also that these may move with the heat input from welding the baseplate in position. It may be necessary to shave more after you have the other welds done.<br /><br />Weld up the seam between the plate and the mount. Tack the points in position, this should be flush with the outside edges but check that the top cap still fits fairly well. The edges can be gently adjusted with a hammer to correct any minor misalignment.<br /><br />The cap should sit easily and line up with the inside edges of the baseplate like this.<br /><br />This is so that you will be able to do an outside corner weld to attach the cap to the sides. It enables a full penetration weld that can be smoothed over afterwards without losing any integrity, and end up with a smooth rounded corner that resembles the original folded one.<br /><br />For ease of installation, there are flattened tack welds to rest the cap on.<br />Fully weld the outside and stitch the inner corners. Recheck that the heat hasn't moved the edges out of shape. <br /><br />Almost done. At this stage it's a good idea to tidy up the welds around the outside and run a wire brush over the inside. This would be the time to prime the inside faces, either in etch or weld through primer.<br /><br />With that done, the cap can be installed. If desired you could weld in a couple of gusset plates in the rail before you put the cap on and finish cleaning everything up. The final step that I recommend is to stitch weld all along the whole rail edges, in inch spacing or every 25mm, to tie the edges down to the floor pan. This will help increase overall strength and stiffness if done throughout the chassis.


I'm not quite ready to install the top capping yet but that's what it would be like.

[2redrovers]

Quick update on a couple of new parts I've got sorted.

Rear chassis rail ends
2mm steel fully tig welded, just attach your crush tubes and drill 12mm holes to match your car
$430 each or $850 per pair includes postage.



Sill repair sections for directly under the B pillar in LH LX UC sedan.
$200 each, including post


Lower outer B pillar sections should be available soon and lower door shell corners /sections after those.


Scuttle corners also coming soon

[Shiney005]

Can you work out postage to Collie in WA for the chassis extensions? PM me with a total cost for a pair please.

[2redrovers]

Pm sent👍

[UCgazman]

Damn I patched my chassis rail ends and already bought some used B-pillars.... Good to see more of these problem area panels getting made though

[2redrovers]

Sorry I wasn't able to help you out with your project, if you need anything specific please let me know and I'll see if I can do something about it.

I'm fixing a car for a customer and aware of the lack of parts you can get. I'm trying to set up for duplicate parts that I need to make because chances are, you guys will need them too.

[2redrovers]

Can you work out postage to Collie in WA for the chassis extensions? PM me with a total cost for a pair please.

Got them finished up today for you, I'll get them wrapped up and posted in the next day or two 👍

[Shiney005]

Another piece of the puzzle complete. Cheers Rodney.

[2redrovers]

Happy to help mate. 👍👍

[Cook]

2redrovers.  Would you happen to be the Rodney that worked on my hatch in Bayswater.  I vaguely remember talk about a Rover. Cheers Ron