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Replace and beef up frame rails?

4.2K views 5 replies 4 participants last post by  HugoW  
#1 ·
Hi,

while the car is up in the air for sills and quarterpanels, I see the frame rails are showing their age / the previous owner's driving style. Their are dented severely. I may be able to bash them into shape again and I consider to bolt the almost-obigatory frame rail chassis reinforcement beams over them. But, I don't like those, drilling and bolting, and creating double layer sheeting (we know what that does at the front...). So, I don't want this:
Image

(BTW, pic nicked from the internet and no intention to dis them, I just don't like them.)

So, I think I will cut of the entire rail between the reinforced ends, and weld a full 4 mm thick U-channel piece in it's place. Of course making sure to keep the car straight and not set the interior on fire while doing it. Is this a know procedure, did I reinvent the wheel or am I overlooking something? I would prep some threaded holes in the channels to make a cross brace, later.

Please share your thoughts, preferably from experience,
Cheers,

Hugo
 
#2 ·
I dont follow the 'frame rail' reinforcement piedpiper 🤭
in my opinion, bolting an over-rail on is just adding a skid as the bolted join can alow movement?

I'm intending to remove & replace the factory 'rail' (floor strengthener) with a shallower section - partly to gain a little ground clearance and partly as I'm looking at a thicker section steel - possibly box-section of ~3mm thickness?

Rich.
 
#4 ·
Thanks for the input. I wasn't aware of the MX5 Restorer versions, nice video on it. I am not sure if I find it sensible money, as I can have them fabricated for € 22,- each without the holes. Those I can drill and the thread insert is not difficult, either. I'll have a look in getting them made and weld them in. At least I didn't come up with another impossible plan, it seems.

Cheers,

Hugo
 
#6 ·
That is indeed the idea, we even have a company semi-close by where you can define the (simple) profile on-line and pick it up a day later for a decent price. I could even have them made out of stainles (304) and weld with a converting wire (is that English?) but that would be a bit over the top, probably.