4th Gens on bigger than stock tyres

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Let me put it this way, we had three Swifts, two five doors and a four door, only one had the wider tires, only one had brake issues and ended up with warped rotors, and the start of the issues coincided with the installation of the tire/rim combination.
That's enough to convince me that the problem was related to the additional rotating mass

I have 235's on my Gen4 Auto, and after 76000Km my discs are like brand new. This is my first change of brake pads.

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Let me put it this way, we had three Swifts, two five doors and a four door, only one had the wider tires, only one had brake issues and ended up with warped rotors, and the start of the issues coincided with the installation of the tire/rim combination.
That's enough to convince me that the problem was related to the additional rotating mass

Umm, I just struggle to see it. Have run bigger tyres on lots of cars and plenty of other people also do. Warped discs (rotors) is also a bit of an urban myth. In 99.99% of cases it is due to uneven carbon build up on the face of the disc. Or is caused by run-out. Thew discs don't actually "warp".

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Let me put it this way, we had three Swifts, two five doors and a four door, only one had the wider tires, only one had brake issues and ended up with warped rotors, and the start of the issues coincided with the installation of the tire/rim combination.
That's enough to convince me that the problem was related to the additional rotating mass

Umm, I just struggle to see it. Have run bigger tyres on lots of cars and plenty of other people also do. Warped discs (rotors) is also a bit of an urban myth. In 99.99% of cases it is due to uneven carbon build up on the face of the disc. Or is caused by run-out. Thew discs don't actually "warp".

I used to always have issues with "warped" discs. I was led to understand it was caused by hot spots. I changed my driving style so that when braking from high speeds, I don't come to a full stop, and let the car roll forward slowly. I haven't had a "warped" disc since.
 

Warping is the differential expansion of a brake rotor due to excess heat build up. A solid rotor will not suffer this as much as a ventilated one as the rotor mass is of a constant thickness whereas a ventilated one has ribs connecting the two rotors together.

Overheating the rotors is caused by excessive braking over short periods of time. Normal driving wont do it, it needs, well you figure it out.

Roger

When you brake, you create friction between the pad and the disc. This friction converts kinetic energy into heat. Hot spots on discs are created in the spaces between the connecting ribs i.e. the thin sections of the discs, so you get sections at a higher temperature i.e. the hot spots. In extreme situations they will show up as blue sections created when the iron reached red heat.

Roger

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I'm considering getting tougher AT or MT tyres on my auto JB74 (last time going off road I had a puncture on the sidewall of one of the OEM tyres that had to be replaced), but from all I've read here I'm a bit worried about its effect on the car performance on road (which is where mine runs about 70% of the time).
If I were to fit 215 75 15 AT tyres such as BFG or Maxxis (easier to find in Brazil) the weight increase per tyre would be around 5 kg/11 lbs (OEM wheels: 7.6 kg/16.8 lbs | OEM tyres: 9.8 kg/21.6 lbs | AT 215-75-15 tyres: 15 kg/33 lbs).
Also, I found these Rays A-LAP-J 16" forged wheels that weight just 4.8 kg/10.6 lbs each. If I had them with BFG AT 215-70-16 tyres (15 kg/33 lbs) or 225-70-16 tyres (15.7 kg/34.6 lbs) total weight increase would be less, respectively 2.4 kg/5.3 lbs or 3.1 kg/ 6.8 lbs.
 

I know it is a bit of a very specific question, but has anyone installed these A-LAP-J wheels or heard from someone who had them installed and could point out if they have helped to keep the OEM performance on road with chunkier tyres? Or could anyone advice on how much that wheel+tyre weight difference would affect performance, so that I could have a better idea if purchasing lighter wheels just for the sake of performance would be worth it?

Sorry to bring up an old thread but you asked there exact same question I was going to ask. I wondered if you ever got any further with this as I'm also looking at the same alloys with an 80/20 road/off-road ratio