Lexus SC300/SC400 front suspension
Here's the problem. It's not about finding rims to fit the Lexus front suspension. You're right, there are tons. It's about finding rims that fit the Lexus suspension that ALSO fit inside the fenders on an A-body. I measured the front end of my car as in the first few pictures, outside edge of the tire to outside edge. Now, that's a really rough measurement, but it's something. I got 69", just like for the SC400 front end. But, here's the thing, my car has no extra room to the outside. So, whatever that SC400 has on it, that's as wide as you can go to the outside. If it's got +50 offset rims (like the factory rims for that car), you're not going to be able to do much to add tire width because anything extra you add has to be on the inside, so more offset. I'm not sure what tires are pictured, they look like they could be fairly stock which would mean 225's. If that's the case, and they're 225's with a +50 offset, even going to a 245 would mean a +70 offset rim. Not going to find a lot of those. The math says about the same. The track width of the 73+ cars is 59.15", plus the rim offset (+6) because the track width includes the rim offset, so the hub to hub should be ~59.6". The SC400 track width is 59.9", which is almost the same, but that's with a +50mm offset factory rim. So, the hub to hub is more like 63.8". That's a 2.1" difference on each side, so, 53.8mm wider on each side than a 73+ set up. On my Duster I run 18x9's with 275's and an effective offset of +27. That means to run the same wheels and tires with an SC400 front suspension my rims would need to have an offset of +80.8. Not going to find those either.
And the A-bodies already have the front to rear offset mismatch straight from the factory if you want to run wide tires. That's why I have a 68-70 B body 8 3/4 in my Duster. If I ran a A-body 8 3/4 with BBP axles my rear offset would need to be +9mm with the 18x10's and 295's that I run, compared to the +27mm offset I have up front. As it is with the B body 8 3/4, my rims are +38 in the back and +35 in the front (the +27 comes from a 3mm spacer and Dr. Diff's 13" rotors that add 5mm compared to the 73+ disks). And really I could use +35 front and rear with the 3mm spacer up front.
Hey if someone wants to try it I'd like to see it. But there are a TON of potential issues. And honestly, when you're all done, you may not have a car than handles any better than one with a well tuned torsion bar suspension even if everything works great. Because really, a well tuned torsion bar suspension is no slouch. The current coil over conversions aren't demonstrably better. The Hotchkis Taxi can lap at TireRack's test track faster than the 2012 3-series beemers they use for testing. That's a ton of work to undertake on a "maybe", even if you have all the skills. I do, I have both the skills and equipment to make that happen if I wanted to, and let me tell you I have zero desire to do it. If you spent a fraction of the time and effort needed to complete that swap you could have a very well handling torsion bar suspension car.
There's nothing unique about the 4 door suspension. They had the same brake options as the 2 door cars. Sure, it's the track width that's listed and that depends on the tires too, but again, there weren't any unique tire or wheel options available on the 4 doors that you couldn't get on a 2 door. Maybe they spec'd the base option which had a different package. As far as the manual goes, it may also be worth noting that you're not looking at an original 1972 manual. That's a PDF, so depending on how it was created it may be different than the original. This is a scan from the '71 dealer book, notice how it shows 2 and 4 doors with the same track. Of course, it also show's the Demon's with a .1" wider track. That may have been a difference in the base option rims or tires. At any rate, any track width difference comes from the brake or wheel options, the chassis and suspension are the same.
Here's the problem. It's not about finding rims to fit the Lexus front suspension. You're right, there are tons. It's about finding rims that fit the Lexus suspension that ALSO fit inside the fenders on an A-body. I measured the front end of my car as in the first few pictures, outside edge of the tire to outside edge. Now, that's a really rough measurement, but it's something. I got 69", just like for the SC400 front end. But, here's the thing, my car has no extra room to the outside. So, whatever that SC400 has on it, that's as wide as you can go to the outside. If it's got +50 offset rims (like the factory rims for that car), you're not going to be able to do much to add tire width because anything extra you add has to be on the inside, so more offset. I'm not sure what tires are pictured, they look like they could be fairly stock which would mean 225's. If that's the case, and they're 225's with a +50 offset, even going to a 245 would mean a +70 offset rim. Not going to find a lot of those. The math says about the same. The track width of the 73+ cars is 59.15", plus the rim offset (+6) because the track width includes the rim offset, so the hub to hub should be ~59.6". The SC400 track width is 59.9", which is almost the same, but that's with a +50mm offset factory rim. So, the hub to hub is more like 63.8". That's a 2.1" difference on each side, so, 53.8mm wider on each side than a 73+ set up. On my Duster I run 18x9's with 275's and an effective offset of +27. That means to run the same wheels and tires with an SC400 front suspension my rims would need to have an offset of +80.8. Not going to find those either.
And the A-bodies already have the front to rear offset mismatch straight from the factory if you want to run wide tires. That's why I have a 68-70 B body 8 3/4 in my Duster. If I ran a A-body 8 3/4 with BBP axles my rear offset would need to be +9mm with the 18x10's and 295's that I run, compared to the +27mm offset I have up front. As it is with the B body 8 3/4, my rims are +38 in the back and +35 in the front (the +27 comes from a 3mm spacer and Dr. Diff's 13" rotors that add 5mm compared to the 73+ disks). And really I could use +35 front and rear with the 3mm spacer up front.
Hey if someone wants to try it I'd like to see it. But there are a TON of potential issues. And honestly, when you're all done, you may not have a car than handles any better than one with a well tuned torsion bar suspension even if everything works great. Because really, a well tuned torsion bar suspension is no slouch. The current coil over conversions aren't demonstrably better. The Hotchkis Taxi can lap at TireRack's test track faster than the 2012 3-series beemers they use for testing. That's a ton of work to undertake on a "maybe", even if you have all the skills. I do, I have both the skills and equipment to make that happen if I wanted to, and let me tell you I have zero desire to do it. If you spent a fraction of the time and effort needed to complete that swap you could have a very well handling torsion bar suspension car.
