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Warning: Extremely long post! Hopefully this will interest some of you. I am from the other side of the world, namely Sweden. I found an old thread here dealing with my car, so I thought I could introduce my project. First a short presentation of myself: The last 27 years I have been working at Öhlins Racing outside of Stockholm, Sweden. I work as a shock absorber design engineer, ridework engineer, and sometimes also as a development test driver. Initially I worked mostly with race cars; Rally Raid (Dakar), Rally cars, NASCAR Cup cars, Super Touring, Dirt Late Model, GT cars and more. Lately, I have mostly been involved in OE road cars; everything from Koenigsegg, Pagani, RUF, Lotus, Polestar and Volvo to others. I have also been working on our aftermarket Road&Track line of shocks for people who want to upgrade the suspension on their road car. There have been a lot of memorable moments too, for instance riding shotgun in a Nextel Cup car sitting on a blanket on the floor, no helmet, no seat, no seat belt, with a two-time Cup champion, lapping a ¾ mile track 0.2 seconds slower than the best lap time during a test… Pretty scary… Another memorable moment was riding with a famous test driver on non-closed German country roads, doing power slides at around 140 mph and hitting 200 mph on a straightaway, all on roads with a 60 mph speed limit. The project actually started as a substitute car for another project that had snowballed; my tube frame, twin turbo Chevy 350, top chopped Volvo Amazon (122). This was in 1988, and I needed a fun car to drive the next summer as the Volvo wouldn’t be finished by then. I had a small budget and made a list of possible cars I could afford. This list contained for example: MGB GT, Lotus Europa (they were pretty cheap then), Datsun 240Z and some others. I ended up buying a 1973 240Z that had been imported from California a year earlier. The idea was to just make the car looking decent and reliable and then drive it more or less as I bought it. I was still going to continue working on the Volvo. I used the Z as my everyday car and in the summer of 1989, I took it on a two-week road trip through northern Europe, making a lap on the Nürburgring Nordschleife and visiting Paris. In the fall I got the idea to put the Chevy 350 in the Z to have an even more fun car the next summer. This wasn’t going to take too long… The Volvo was still the main project… A one year long stay in Germany plus being a time optimist meant that the car wasn’t on the road until -96. That year it had the 350, a Muncie M22 and the stock peg leg third member. It was pretty quick and fun, and I attended a Nissan Z-club track day event. All the others thought the car would plow through the corners with the ”heavy V8”. It didn’t. I think I had the first V8 Datsun in Sweden. We have pretty strict registration rules, so in order to get it registered I had to have a fake dyno sheet showing the engine only having 160 horses, while it at that time had around 360. I also detuned it with exhaust restrictors and a throttle stop during the inspection. During 1997 the car stood still, receiving a BMW E34 M5 third member, a new clutch and a new cam. I drove it again in -98, now having 420 horses and spinning both rear tires. Now the focus was on the Z, and I realized that I wouldn’t continue on the Volvo, so that project was sold in pieces. Since I like sleek cars with a low roof, I planned on chopping the roof on the Z as well, having the car ready for the road the next summer. With the experience from the Volvo, the plan was to make modifications every winter, small enough to have car on the road every summer. Yeah right… I haven’t driven the car since then! When you modify a car in Sweden, you can register it as modified car or a completely homebuilt car, depending on how big the mods are. The benefit of having it as a modified car, is that you retain the year model, which, if it’s an old car, means that there is no tax to pay, exhaust emission tests are easier to pass and other benefits. Nowadays, you don’t even have to take the car to the annual inspection if it’s more than 50 years old. My plan was to keep the mods within the range of the limits for a modified car. It would have a roll cage, bigger brakes, tires and wheels and some Öhlins inserts in the stock MacPherson (and Chapman) struts. The chassis (floorpan) would be kept stock, otherwise it would go into homebuilt car territory. While I chopped the top, I built an integrated chrome moly roll cage. It is welded directly to the roof, and the A-pillars are consisting of the cage tubing itself, with some hand beaten sheet metal welded on. I made it this way both due to the space constraints of the small cockpit and also to hide it as much as possible for a stealthy look. Now this project also snowballed in exactly the same manner as the Volvo, so over the years I have had a lot other substitute cars to have something fun to drive during the summers. Naturally, I worked on them more than planned too, delaying the Z even more… I have had a few Porsches and a pretty brutal Lotus Seven replica with a 420 horsepower supercharged BMW M60 4 liter V8. For some reason, many people were scared riding shotgun in that one… In order to have a good weight distribution, I always wanted an all aluminum V8 engine. The initial plan was to build an aluminum Chevy SB. When the LS7 crate engine came out, I realized this was a better choice, so in the fall of -06 I bought one. It arrived three days before my birthday as the best birthday present ever! GM hadn’t even come out with an ECU and wire harness kit for it then. I am almost certain it is the first LS7 in Sweden. Earlier I had bought a Borg Warner T56 transmission from a 1996 Camaro. I am still planning to use it, even though I will have to modify it to fit the LS engine. In 2011, the car was maybe one month’s hard work away from a possible illegal test drive. After thinking back and forth for a long time, I came to the conclusion that I wanted to build a full tube chassis car to get the full potential of the car. This meant it would have to be registered as a homebuilt car. I planned to build my own double A-arm suspension all around, maybe even making my own spindles. So, in 2013, I raised the car up high from the garage floor, welded on sturdy stands that I bolted to the floor and then I cut the entire car floor away! I thereby threw away hundreds (maybe even thousends) of hours of work. At one point I was contemplating building a chassis from aluminum honeycomb sandwich panels, but the organization inspecting homebuilt cars doesn’t like that building method. Instead, I decided to build a tube frame, but to replace the triangulation in the cockpit with homebuilt sandwich panels made from aluminum sheets with a hard foam core. They will be glued and riveted to the steel tubes. This will increase the torsional stiffness a lot and also reduce the need for temperature and noise insulation materials. The car will have a completely flat underside and the exhaust will run throught the enclosed transmission tunnel, which also will increase stiffness. In order to be able to design the chassis, I have manually scanned the car body and the roll cage using laser instruments, tape measures, spirit levels, carpenters squares, cardboard templates and more. I have many hundreds of hour in this. I have also modeled the car body in Blender, a free software that is quite amazing! I built a wooden mockup of the cockpit to test different driving positions and general packing of components. Since the car will be very low (1120 mm or 44 inches), and the cockpit is quite narrow, there is little space for seats. I decided to integrate them with the chassis. So now you will sit on angled sandwich panels connected directly to the floor. The seatbacks will consist of a rear firewall panel going from side to side, also further stiffening the chassis. In the fall of 2014 I took yet another project changing decision. By this time, I realized that my time optimism would mean that that the car might actually never be finished. Instead of building a full custom suspension, I decided to buy a donor car with good suspension and use those parts without huge modifications. I decided on a BMW E39 with a multilink rear suspension and MacPherson front suspension with divorced lower spindle joints. The plan was to modify the front suspension to double A-arm (or more correctly multi-link). I would also stick with the suspension rubber bushings, as by now I didn’t have the same need to have a car only optimized for super quick lap times. I had started to enjoy a more mature, sophisticated suspension with good comfort too. This came a lot from having done the design and ridework on all Öhlins dampers used on Volvos and Polestars during this millenium. This doesn’t mean that the car will be slow on the track, but I’m willing to trade maybe a second or two for a more comfortable ride. After having spent countless hours designing the tube chassis in the CAD and having received an OK designwise from TESTA, an organization inspecting homebuilt cars, I started building the chassis in the summer of -21. In the summer of -22, I took the rear suspension to my job and used our $100K FaroArm scanner to 3D scan all the parts. I assembled the full suspension in the CAD and took all the suspension points and input them in a suspension software to get all the suspension geometry characteristics to base the placement of the rear subframe in the chassis on this. The front suspension will be designed to harmonize with the rear suspension. After realizing that there will be a big caster change with steering lock if I modify the BMW front suspension to double A-arm, I decided to buy brand new Corvette C7 suspension parts instead. Very early on in the project a dream I had was to widen the entire car instead of just slapping on a set of big fender flares, but for a long time I realized that fender flares still were a more reasonable option due to the amount of work involved in widening the entire sides of the body. However, in late 2022, another major project decision was taken. Since the project had already taken way too much time, why not make the car the way I really wanted it, even if it would mean yet a few years build time? I decided to design a full custom body in fiberglass, only keeping the steel roof! The main design DNA from the original Z will be kept, but the proportions changed to be more modern, agressive and cool in general! I have tried a lot of different shape changes to different parts of the body, and I am not fully done yet, but I am pretty close. I know that many people think the front spoiler is too big and it looks like a snow plow, but I like it that way. I have also looked at the design many thousends of hours, so if you give it some time, maybe you will like it too! In order to balance the car aerodynamically, I know there should be a rear spoiler or wing, but I really like the look without either one. The way the end of the roof meets the rear fenders is really good looking in my mind. I really hate extra gaps between body panels and unused attachment points. Otherwise, I could make a pop-up spoiler from the rear part of the body, as many modern cars have. I could also have an attachable rear spoiler or wing and just have some plugged attachment holes when not used. Unfortunately, my sensitive design preferences prohibits this. What I may do is to make the tail light panel able to slide rearwards and enable a spoiler coming up in a slot above the tail light panel. Or I will come with another solution… Or design a spoiler or wing that I like… We’ll see… I will make the fiberglass body in the following way: After finalizing the design in Blender, I will 3D print the body in parts that will be glued onto a base that is attached to the tubeframe. This will then be bodyworked to perfection and molds will be pulled from this. I can then create the different body parts from the molds. The rear part of the body will be attached to the steel roof, that is all that is remaining of the original 240Z sheet metal… Ideally, I would like to be able to get a good enough finish of the gelcoat, meaning that the only part that would need to be painted would be the roof. I think it should be possible to color match car paint to the gelcoat color, We’ll see in the future… When I bought the car, it was meant to be something fun to drive while my tubeframe Amazon was being finished. Instead, the Z-car project also snowballed. Of the more than 35 years I have owned the car, I have only driven it three summers! Of course, I have had quite a few other fun cars over the years, but many years, I haven’t had a sporty car to drive. Maybe this has kept me alive, I don’t know… The first few years when I realized I wouldn’t have a cool car to drive the next summer, I was really frustrated. Luckily due to my job, I have driven and ridden in many sporty and extreme cars, so the need to have one myself has been reduced over the years: The building process itself has become more important than the actual finishing of the car. Anyhow, in hindsight there is a lot to learn from this. I know at least a couple of things I should have done differently: 1: After getting the car on the road with the first V8, i should have stuck to the plan to only make small changes every winter to have it ready to drive the next summer. 2: When the car was maybe a month away from being possible to drive with the LS7, I should have stuck with the plan to just put fender flares on it and finish it like that. After that, I could have started a brand new project from scratch, if I felt the need. As it stands now, I have a lot of design compromises due to the ever changing project goal. I have also destroyed a car that is now quite valuable… If I knew from the start that I would end up building a custom tube chassis with a custom fiberglass body, it would have been much quicker and cheaper starting from scrath than using the 240Z as a base. But I guess that’s what project creep does… especially when it’s project creep that has been going on for half of your life. When people asked me 15-20 years ago when the car would be finished, I jokingly said ”when I retire”! We’ll, I am planning to retire in two years, so that line is not a joke anymore! This project has taken up a huge part of my life, both regarding practical work, design work, planning, purchasing, but mostly dreaming, worrying and thinking about it in general. Will it be worth it? I don’t know! I just hope it’ll be reasonably finished and at least registered and driveable sometime before I will take the dirt nap. Comments and questions are welcome! As are sponsors! For those interested, the project can be followed here: https://www.facebook.com/MechanixMenace/ https://www.instagram.com/mechanix_menace/ https://www.pro-touring.com/.../107091-quot-Mechanix... https://rejsa.nu/forum/viewtopic.php?t=125262&postdays=0... https://www.youtube.com/@mechanixmenace870