260DET

Your option 2 would be fine to 300 whp only, drags and drifting excluded, a Z32 box is fine for 400 whp, you will need a R200 diff with suitable CV axles. Plenty of LSD options, my choice would be the most expensive (as usual) a OS.Giken. 400 whp can get quite expensive for it to all hold together and take a bit of abuse.

Go with your first choice, the 4x114 to 5x114 adaptors. As you said they are available in the thicknesses you need and are a structurally sound option.

My dreams exceed my capacity so this idea has been put to bed. But there is a turbo version of the Mazda 2.5 which obviously has a lot of potential, if I was proceeding that would be a favourite.

OK, no Z this time, one of my favourite cars at the Nurburgring.

That's one of the good things about the US, if it works there is no need to change. Elsewhere there is too much trendy keeping up with the latest, good or bad, appropriate or not.

What you have done is better, it's added very little extra weight while adding considerable strength where needed.

Manuals are so yesterday, get a DCT conversion, it will shift faster than you can and they are not relatively heavy. Particularly compared with a CD009 lump. That's if you want the best performance option, what is the point in handicapping a good engine with a less than optimal transmission?

I'm liking what has been done here and the thought process involved. Keep going. What was done to my sills/rockers was to simply run some square tube underneath against the pinch weld flange and weld it in place. Makes jacking easy too anywhere along it.

Seems like you have not made a decision yet on door area impact strength. My decision was to go with composite doors incorporating a separate light weight tube steel frame to connect to the hinges from the latch. The doors were then filled as far as practical with foam which cushions and spreads impact. Importantly the car has a basic cage which adds to impact protection and stiffens the body too. So what I suggest is deciding if the car is going to have a cage and go from there. I'm quite confident that my setup will provide excellent protection.

Historic spec S30 showing how to drive this circuit.

Always post pics, gets more interest. I understand that you are looking to blend the kit panels into the body, as grannyknot said your 'panel bond' should come with instructions but blending is the problem. I'd like to know the answer to that too without adding excessive weight.

Epic thread in the just cause of losing weight, great to see, just don't forget that Group 3 cars weigh up to 1,300 kg and do lap times that us Z punters can only dream about with modest power.

Agree, may be OK for crash protection but no good for chassis reinforcement, particularly on one side.

Another vote for strong frame rails no matter what the application. What i do is weld some RHS along the pinch well and brace it back into the body in a few places. A bonus is it can be used as jacking/stand points, very handy.

As far as coilovers go MCA have a well deserved superb reputation in my country, see https://mcasuspension.com/shop/catalog/302/240Z They did me a three way custom setup years ago, low and high speed bump, rebound. On my favourite circuit there was a turn in problem with one corner so after doing some research I did two clicks on the low speed bump, problem solved, unreal. That corner was the straight entry corner, two clicks to go from 'turn in you bitch' to whoah, PB coming up. My point is that the best dampers and knowing what the adjustments do is everything. Before you ge