Aventador custom chassis drawings for 500 USD / 470 EUR

[plans4sale]

 The upper front A-arm is in fact replaced by two separate linkages with 2x2 pivots instead of using a traditional single one with 3 pivots.
http://i.imgur.com/sSUK4AB.png

 As for the lower rear A-arm, it's a regular design, though it's inequal type, in a very similar fashion like the Ford GT40's separate linkages (except that on my design it's a single A-arm). The front linkage of it will take the huge torque during acceleration, whereas the back linkage will be mounted 150 mm closer to the center of the car than the front one, in order to allow less sideways shifting of the rear wheel while it goes up or down. As a side effect, this will also reduce the friction between the rear Corvette C5 hub-bearing and and the axle.

[76mx]

P4S, what is a two link upper a-arm? Does that mean it has two of what are called "pick-up points" instead of three? Also, do you mean that the back lower a-arm is 150MM longer than the front as you say, or is it 150MM wider as measured from a transverse centerline between the two lower rear ball joints?

[Tallon]

Ah I'm glad it wasn't just me thinking that, it didn't even seem like the seat belt was holding him back lol

[Digibeam]

Guess we should stay away from large immovable small radius solid metal trees when driving on the sidewalk.
Other than that, these are controlled/forced events, I found it interesting that the seatbelt did little to prevent leftward motion.... So if it's structure concerning you it's one thing, the restraint system is another.
I also noticed the driver did "little to nothing" response wise, to the obvious object in the vehicles path...
What sort of dummies do they have driving in these tests?
Swerve and avoid people..... Swerve and avoid......
 

[Tallon]

Ouch! So what exact changes can be made to push the car away from the object rather than pulling it in? I see the additional triangulation added on the bottom to match the top

[plans4sale]

So you purposely did not follow a proven design, which was made with a lot of r&d money?.

Just curious.

 As I mentioned in my previous post, the Diablo and the Murcielago chassis are both not safe enough in the case of overlap frontal crash. Not to mention that old EuroNCAP crash test were done at lower speed and the cars were hit along the whole front end, whereas the 1/4 overlap crash test was introduced just in the recent years (and this is why many of the 5-star and 4-star cars eventually received surprisingly poor ratings on the additional re-run of their crash tests). I can't find the exact article where I watched dozens of videos with these failed crash tests of previously known as "safe" cars, but even this one will pretty much show the origin of the problem: http://jalopnik.com/watch-this-absolutely-brutal-crash-test-of-a-mazda-cx-9-1560931424


 As for the suspension. For some unknown reason, despite the thousands of engineers and huge amount of money and time invested in R&D by so many (sports) car companies over the years, their suspensions still fail to provide proper camber angle during high-speed cornering (unless they manually increase the camber angle for the track-only cars). I evaluate the car suspension performance since over a decade, and based on my observations, even the camber angle used in modern OEM sports cars is simply wrong. The most tricky thing is to keep best possible contact between the tyres and the road. As the tyre's lower cross-section shape will get heavily twisted during high-speed cornering, a huge amount of friction and weight forces is being transferred to the outer side of the tyre (for example, this is the front left tyre when the car does a turn on the right side), whereas the inner side of the tyre is being unloaded and sometimes it even loses contact with the road. This is just a quick example of the problem:

 http://i.imgur.com/wmI2AP2.png

That problem is further increased by the fact that the wheel will not strictly follow what the engineers predicted in their CAD simulations, because under the shifted weight forces in this conditions the location of upper and lower ball joint pivot points changes a bit. This is especially true for suspensions based on polyurethane bushings instead of metal ball bearing mountings, where the change could reach as mush as 10-15 mm than the original position. Even with metal ball bearing mountings (rod ends etc), there is still a certain amount of change of the wheel's camber angle compared to what was supposed to be in the CAD design. The hub-bearing will slightly bend under the massive forces taken during high-speed cornering. This is why I designed my suspension to compensate for these loses in camber angle, so that it will be safer and offer better performance in the cases where the car is being driven faster in the bends.

[Onewickedsvt]

So you purposely did not follow a proven design, which was made with a lot of r&d money?.

Just curious.

[plans4sale]

 The chassis is primarily designed to be used with a few Aventador body kits that are currently being developed by other builders. As far as I know, at least two of these are based on the Aventador 3d game model from the video game "Forza Motorsport 4". I, too, used this 3d model (though heavily improved by me for better accuracy) as reference for getting the main proportions of my chassis. However, since these plug/body projects are done by other people, I can't speak about their accuracy or whether they will fit perfectly to my chassis (the roof pillar, for example, can be a bit off, the rest should be able to fit with ease). My chassis is totally custom design, purposely not following the usual Diablo and Murcielago chassis designs as I find them having too many weaknesses (especially in the case of side impact or overlap frontal crash, i.e. when the car is being hit only at either side of the front bumper).

[Digibeam]

That's very interesting information, I would hope no one would attempt a high speed corner, but assuming everything holds together it looks pretty good.
I like the frame,   Is it specific to an Aventador body that is in fabrication? Or is it designed to be used as a standard?

[plans4sale]

 Dave, there were some improvements I made on the roof, mostly on the Roadster version. Stay tuned for the new drawings.




 New update, with the following key features:
 
 1. The engine cradle is different now, 300 mm narrower at the back end compared to previous version. I will have to redo most of the engine cradle drawings. As a result of that modification, rear lower A-arms are inequal length - their back side is 150 mm longer than  the front side. This will provide a better suspension travel in the case of  high-speed cornering, while maintaining the same strength of the A-arm  during acceleration. Weight is reduced by about 1.4 kg as well.
 
 2. I already finished with testing and figuring out the best performing suspension geometry for the front wheels. I started with the 3d modeling of it, using real parts as reference 3d models (Corvette C5 hub-bearing, QA1 coil-over, QA1 X-series 5/8 rod end, Master-sport lower ball joint, custom made wheel hubs). Eventually, I may also design an alternative lover A-arms, front and rear, that use some different lower ball joint that's largely available in the US. At this point I don't own such part to take exact measurements of it, so I can't turn it into a 3d reference model.
 
 3. As I use more aggressive camber angle for the steering pivot, I decided to use two-link upper A-arm instead of regular single upper A-arm. This will allow to manipulate both, the camber angle and the castor angle, while taking a turn. During a high-speed cornering, the outer wheel's camber angle will be double that of a usual sports car (http://i.imgur.com/wmI2AP2.png), in order to keep maximum area of contact patch of the tyre on the road surface, as well as to reduce heat and friction in the wheel bearing. Although it may sound strange, in some cases the inner wheel's castor angle will become negative, thus reducing the body roll and the aforementioned aggressive camber angle when it's not necessary (inner tyre will take less than 10-20% of forces as the majority of weight is being shifted to the outer tyre, so there is no reason for the former to be inclined). All of these advantages are not possible with regular double A-arm design.
 
 In the following days I will send updated drawings with the included changes I made recently, plus new drawings for the rear bumper, suspension A-arms and wheel hubs.
 
http://i.imgur.com/QBaZ9YI.png
http://i.imgur.com/Fl93Jk2.png
http://i.imgur.com/va6nz3R.png
http://i.imgur.com/OxXykFm.png
http://i.imgur.com/OYl2MT2.png
http://i.imgur.com/e288Xhd.png
http://i.imgur.com/ycXP15G.png
http://i.imgur.com/m9PuOUD.png

[italianknightrider]

O K ,this is the C5 Bracket set for the front suspension ,we now have the ability to use C4 or C5




we are still waiting on the roof plans we ordered !!




IF YOU get one of these frames drivable then you can sell more of them , people are waiting to see someone make the suspension fit and work !!

[plans4sale]

 Update: Sending next wave of chassis plans tomorrow.

[italianknightrider]

IKR, the Chassisworks plans and the NAERC plans were for a Diablo. An Aventador has over 4" wider track in the front and over 1" wider track in the back. An Aventador also has wider wheels than a Diablo in the front and narrower than a Diablo in the rear. You cannot just copy the chassis and suspension dimensions, you must account for the track and hubface differences in order for the wheels to sit correctly in Aventador body wheelwells. If you are not using stock wheel offsets, also account for it now so that you will not need spacers later.   

our Front box will be 26 1/4"  and the Rear frame rails outside to outside will be 26" using C5 Suspension up front

[76mx]

IKR, the Chassisworks plans and the NAERC plans were for a Diablo. An Aventador has over 4" wider track in the front and over 1" wider track in the back. An Aventador also has wider wheels than a Diablo in the front and narrower than a Diablo in the rear. You cannot just copy the chassis and suspension dimensions, you must account for the track and hubface differences in order for the wheels to sit correctly in Aventador body wheelwells. If you are not using stock wheel offsets, also account for it now so that you will not need spacers later.   

[italianknightrider]

WORKING OUT A DEAL TO GET THESE 3/8" UPPER MOUNTING BRACKET / PLATES CUT OUT FOR THE C5 FRONT SUSPENSION UPPER CONTROL ARM