42093 scale cars with swappable engine - NEW ADDITIONS!

[johnnym]

Has been a while since I last showed some of my creations. I recently did an alternate model for the 42123 set with a special functionality and wondered if something like that could not also be done with the parts from 42093. And this is the result, the MDB attaccabrighe - an Italian fastback with gull-wing doors and a high-powered supercharged I4 engine (currently not fully color correct because of unavailable parts and also still WIP):

Now about the special functionality: It's engine is swappable! So far you can use an I3, a V6 and a V8 as replacement engine for the stock I4 engine (all engines also compatible with the AMX 4s). The original I4 of the AMX 4 Turbo and the original V5 of the AMX 4 Biturbo can't be used unmodified in the attaccabrighe though, as it's engine bay is 2 studs narrower than the one of the AMX 4s and the V5 also requires a different crank shaft. The engines are attached to either two axle holes or two pin holes.

The attaccabrighe will eventually be made available on Rebrickable and also receive a selection of aftermarket parts (like the ones for the AMX 4s) and maybe also some OEM modifications (e.g. wide rear wheels!)

Sports cars like the AMX 4s or the attaccabrighe of course also need an opponent apart from themselves. And there is one car that has enough potential to keep up with them - the MM Hammond Executive. More on that one later, for now just one picture showing a WIP model aside the attaccabrighe:

 

 

[The01]

Both cars look pretty good! I very like gullwing doors. The swappabl engine is also a cool feature which is a easy way to customize a car like you would with a real car.

[thekoRngear]

Awesome! All the swappable engines look really cool!

[johnnym]

Thanks guys! Despite what people say about its rear axle construction, the missing differential in the 42123 McLaren Senna really allowed for some rethinking. I have to give the creator of this set credit for that, and also the people that started the 42093 scale cars.

BTW, I also created a video showing the AMX 4 Turbo on a dyno-like machinery and might come up with something similar for the attaccabrighe in the future:

 

Edited March 14, 2022 by johnnym
added link

[Thirdwigg]

Great job with build. I have recently become a fan of "system builds" that allow for interchangeability and flexibility, and I'm happy you took this approach with this build. It takes a lot of system thinking to make sure all compentants can work together and interchange.

Good job, and I hope to see more like this in the future.

[johnnym]

Thanks for your kind words, I greatly appreciate that from you @Thirdwigg.

On 1/19/2022 at 4:35 PM, Thirdwigg said:

Good job, and I hope to see more like this in the future.

Well, there's already a third car with similar functionality - the police interceptor - but having its engine at the front makes its engines incompatible with the AMX 4s or the attaccabrighe. But due to having five crank pins by default, I5 and V10 are possible without changes to the car, although the engine bay is much smaller compared to the rear-engine cars, limiting the details. A bigger scale for such functionality would surely be better. So maybe it's time to make something similar in the scale of my Turbo Racers, but I also want to give the car from 42098 a try, though the available parts for the car alone are even less than available from the Corvette.

Edited January 25, 2022 by johnnym
missing word

[johnnym]

The 42098 alternate model - actually only made from the parts of the blue car that came with 42098 - is ready. This one became a very simple - no-bullsh*t - track car. So no windshield, no doors, no roof, no engine cover, just pure driving experience.

Presenting the McKall StarFighter - also known as the pocket rocket internally at McKall.

The car features HOG steering with a 20 tooth gear directly attached to the steering axle - yeah, it's a little primitive, but it also avoids a visible steering knob ruining the shape of the body. The stock turbocharged I4 engine is of course swappable. The big V8 engines fit snugly, but fit in:

Of course I cheated a little and show it using wide wheels at the rear whose black rims are not part of 42098 and also not part of the blue car's inventory, but manufactures usually show their cars with extras on, so what.

[Void_S]

Looks nice, but for RWD car with a rear engine I would personally love to see more convenient longitudial engine placement, not traversal one. And, I know the parts are limited in color choose for alternate models, but curved panels on the hood (front compartmen) will look better being in dark azure. My inner perfectionist could not leave it unmentioned 

[johnnym]

22 hours ago, Void_S said:

Looks nice, but for RWD car with a rear engine I would personally love to see more convenient longitudial engine placement, not traversal one.

Now that's odd. I assumed from the front engine FWD cars I had in real, that putting the engine like that - transversal - in the rear would be the easiest thing for a RWD car. But as you said and what I read afterwards, in reality it's not so common, though there are quite some cool cars that had/have it that way (for example Lambo Miura, Honda NSX, Toyota MR2, Pontiac Fiero, etc.), but literature calls them rear mid-engined then.

But why is that? Wouldn't it be easier from a mechanical standpoint to put it in transversely close to the rear axle?

Quote

And, I know the parts are limited in color choose for alternate models, but curved panels on the hood (front compartmen) will look better being in dark azure.

Well, maybe that's something for a modification or the aftermarket. I have to say I kinda like the black hood with the red stripes and I believe there's also no pin with pin hole in dark azure, yet, so this spot would still stand out.

Edited January 26, 2022 by johnnym

[Void_S]

12 hours ago, johnnym said:

But why is that? Wouldn't it be easier from a mechanical standpoint to put it in transversely close to the rear axle?

Well, this question is not as easy as it may appear at the first sight. Mechanically, yes, it can be easier but has a lot of counterweights:

1. Traversal placement works for smaller engines. A huge powerful engine may just not fit due to the limited width of the vehicle (plus extra space for the cooling system around, which is more complicated for a rear-engined car).
2. The powerful rear-engine + RWD combination will have performance issues with the traversal engine due to non-symmetrical driveshaft lengths. It makes no sense for compact FWD city cars but is critical for sportcars and supercars (no torsen/lockable differential possibility, no, sorry, we still can't violate the physics - different left-right driveshafts handles the torque differently).
3. Why I mention sportcars and supercars? Because they, with their rear-engined (even more, rear-mid-engined) architecture sacrifice the passenger/baggage compartments for better weight distribution and performance. So, it is their main purpose. While compact traversal engines are purposed by themselves for less space consumption, which is normally not a problem for sportcars and supercars. So there is no need to solve the problems (with a cost of worse cooling, worse maintenance access, underperformance, etc) which are actually not presented for such car classes.

As for others, like Honda NSX, Toyota MR2, Pontiac Fiero - they are sport-ish cars but compact ones, first of all. So the p3 above answers why they do have such a scheme but many other cars do not.

[johnnym]

@Void_S:

Thanks for your in-depth explanations, very interesting stuff! About this one here:

On 1/27/2022 at 12:00 PM, Void_S said:

we still can't violate the physics - different left-right driveshafts handles the torque differently

I suspect this is mostly likely relevant for high-speed driving? Because aren't there a lot of trucks that have their differentials at an offset from the center line of the vehicle? And I assume torque is much higher there than for sports cars.

BTW, sorry for not coming back to you earlier, but spare time went into digitizing the attaccabrighe, which now allows me quick recolorings and hence a sneak peak at an early modification that will feature a VR6 engine:

Sorry, the StarFighter is not yet digitized, so no dark azure front fenders for now.

[Void_S]

4 hours ago, johnnym said:

I suspect this is mostly likely relevant for high-speed driving? Because aren't there a lot of trucks that have their differentials at an offset from the center line of the vehicle? And I assume torque is much higher there than for sports cars.

Nope, it makes sense only for high-torque start. At the high speeds such things are irrelevant as the torque moment becomes too small. The diffrenence between trucks (and other solid-axle vehicles) and FWD cars with "transaxle" is in the half-axles lenght diffrenence (when one shaft may be twise or even more shorter, while for solid axles it takes only a few percents) and the fact that CV connections are always angled, so for siginificatly shorter shaft the angles are even bigger and increase the torque resistance. Some FWD cars even have different thickness of them (left-short is empty inside) to compensate this effect somehow. 

[johnnym]

@Void_S: Ok. thanks for the clarification. As already said, very interesting stuff. You might wanna have a look at the police interceptor above. It has a more realistic setup and a diff. I'll get some pictures up sometime in the future.

[Void_S]

Always, youre welcome)) 

Besides these things, it is still Lego, and whatever is possible. I spent some time to find that here the engines not only looking nice but really have working function. Love these cute small-scaled models! 

[johnnym]

12 hours ago, Void_S said:

Always, youre welcome)) 

Besides these things, it is still Lego, and whatever is possible. I spent some time to find that here the engines not only looking nice but really have working function. Love these cute small-scaled models! 

Thanks a lot, that comment made my day!  You're welcome.

[johnnym]

Instructions for the MDB attaccabrighe are now available from Rebrickable. Those are for sale, so hopefully I don't disappoint someone with that, but the effort I usually put in premium instructions is considerable. Plus I created a sort of sporty trim for it to smooth out the shaping and get some "real" wheels on it, 42093 unfortunately fell short in this regard.

BTW, if you're still wondering about the name, attaccabrighe is Italian for brawler, think of Bud Spencer...

Here are a few pictures showing the SC package on the attaccabrighe. The rear spoiler and skirts really make a difference IME:

[Arioh]

Damn, love concept of swappable engines. Really cool work.

[johnnym]

Thanks, glad you like it! Wanna give an alternate engine of your own a try? I'd love to see that. The digital models (Studio files) of my alternate engines are available at no charge from Rebrickable, you can actually check them out directly in your web browser with the 3D viewer they use at Rebrickable or use their digital model as basis for your own creations:

• turbocharged V6 engine
• turbocharged V8 engine
• twin-turbocharged I3 engine

[Arioh]

Will check. Maybe try to do my onw takes on such idea...

Sorry to ask but, can you provide dimersions of your engine bays and engine mounting points? Thinking to them interchangible...

[johnnym]

3 hours ago, Arioh said:

Will check. Maybe try to do my onw takes on such idea...

Great!

3 hours ago, Arioh said:

Sorry to ask but, can you provide dimersions of your engine bays and engine mounting points? Thinking to them interchangible...

Indeed, thought about that, too. Let me check, I don't have them in my head right now.

[johnnym]

Well, it's a little complex - and I already lost the following written stuff once due to fat fingers - so let's start with the easiest one:

• the engine bay of the StarFighter is 9 studs wide, 6 studs long (-1 stud at the bottom to the front, 7 studs apart for the two axle connection points, +1 stud at the center rear end, 5 studs wide, +1 stud on each corner of the rear end, 9 studs apart) and has a head room of 6 studs to the top of the rollover bar
• the engine bay of the AMX 4 is:
  • 1st layer: 11 studs wide, 9 studs long (-1 stud, 7 studs wide in the rear center) and with a head room of 1 stud at the rear and 3 studs at the front
  • 2nd layer: 9 studs wide, 7 studs long (+1 stud, 5 studs wide in the rear center), 1 stud high
  • 3rd layer: 9 studs wide, 6 studs long (+2 studs, 5 studs wide in the rear center, -1 stud at the bottom to the front, 7 studs apart for the two axle connection points), 2 studs high
• the engine bay of the attaccabrighe is:
  • 1st layer: 9 studs wide, 8 studs long (7 studs widee at the front, 1 stud long) and a head room of 1 stud at the rear end and 3 studs at the front
  • 2nd layer: 9 studs wide, 8 studs long, 1 stud high
  • 3rd layer: 9 studs wide, 7 studs long, 1 stud high
  • 4th layer: 9 studs wide, 8 studs long ( -1 stud at the bottom to the front, 7 studs apart for the two axle connection points), 1 stud high

All the above mentioned engines and the V8 of the AMX 4 HE fit in all cars. The stock engines of the AMX 4 Turbo (I4) and Biturbo (V5) only fit in the AMX 4s.

[johnnym]

I'd like to give an update on these cars with swappable engine as there were a few additions in the meantime:

• I created a modification of the MDB attccabrighe with VR6 engine - like a real VR6 this one has a vary small cylinder bank angle. Apart from the features of the original attacabrighe - like the gull-wing doors - this features some design updates and color cleanups that IME further smooth up the looks, compared to the SC package. But judge for yourself:

• The McKall StarFighter was digitized and is available for sale on Rebrickable since a few days. @Void_S: I hence also rendered a special version of it for you.

I also just yesterday started to create a closed version from it. This should also feature doors in the future, but not yet implemented. It also features a new V6 motorbike engine with additional turbocharger and intercooler and updated exhaust system (both will also be available separately from McKall for the StarFighter). Well, it's still work inprogress, but I like its looks so far. Have a look-see:

• And I also had my way with the 42106 set (actually parts only as I don't have it, so there are still some color mismatches here and there) and look what came out: I call it the DieselBolt, for it features a large I4 marine diesel with twin-turbochargers. Due to its construction, it should work with all swappable engines I have created so far. It also features doors, a single seat, dashboard, gear lever, etc.. Steering angle is very good for this model, compared to the other models so far.

Edited March 14, 2022 by johnnym
corrected typos

[Void_S]

23 hours ago, johnnym said:

The McKall StarFighter was digitized and is available for sale on Rebrickable since a few days. @Void_S: I hence also rendered a special version of it for you.

Thank you! Actually, I should excuse as now, comparing the original black-hooded model and recolored one, with Dark Azure panels, the back one still looks better 

The latest "hot puckup" reminds me a kind of reversed Hot-Rod, when not the front end but tail is "naked" to expose the oversized engine. I don't know if these trucks have some common name, but I must admit I love them more (even if they may not exist in real life, yeah the dragons...) over "regular" hot-rods. 

[johnnym]

9 hours ago, Void_S said:

Thank you! Actually, I should excuse as now, comparing the original black-hooded model and recolored one, with Dark Azure panels, the back one still looks better 

Hey, it was worth a try and the Eyesight renderer of Studio doesn't exactly produce perfect colors, so in reality it could look different, though I also still prefer the original one.

9 hours ago, Void_S said:

The latest "hot puckup" reminds me a kind of reversed Hot-Rod, when not the front end but tail is "naked" to expose the oversized engine. I don't know if these trucks have some common name, but I must admit I love them more (even if they may not exist in real life, yeah the dragons...) over "regular" hot-rods. 

Thanks! I also don't know if these have a common name, but I was really tempted to give it a try after discovering this one here:

https://www.whichcar.com.au/features/mid-engine-holden-rodeo-track-monster

....which - of course - has its engine longitudinal, but yeah, doesn't fit in my concept, so I changed that to be "compatible" with my existing cars. And yeah, I also love these pickups - even if they don't have a functional bed.

[johnnym]

@Void_S: Had some thoughts this morning, and, you know, although I prefer that rear-engine Pickup over front-engined Hot-Rods, those Hot-Rods (with open engine bay!) would allow for a much easier integration of a swappable engine than my front-engined MM Hammond Executive, where engine space is fairly limited. I think I will look into this area and maybe come up with a Hot-Rod with swappable (front) engine in the future.

For now here are a few pictures of the MM Hammond Executive as police interceptor (still a little unfinished due to missing parts in correct shape or color). It features:

• four openable doors
• front and back seats
• openable trunk with spare wheel and steering knob
• swappable front engine (I5 standard and V10 as upgrade available) with RWD
• steering which is done by putting the steering knob into the exhaust

I think the front could also be used for a Grand National and I am also thinking about a pullman version in the future.