E30- S65 Swap and 3D Scanning

[raceablestreetcar]

Ah, so the subframe is hard-mounted to the chassis, and then there is a poly mount on the engine arms?

Correct, it is solid mounted to the chassis in the same 4 locations as the OEM crossmember, and there are the two additional mounts where the lollipops used to be. The poly mount is tough to see but it is where the engine and crossmember meet, similarly to the OEM system, just a bolt through mount instead of a pedestal style mount.

[Panici]

Thanks! Right now I have a universal poly bolt through mount. There are options for different durometer ratings of the poly, but no rubber option. There is a poly option that is very similar in stiffness to an OEM rubber mount. I chose this mounting solution as it is cost effective, and easier to manufacture than using an OEM style mount.

Ah, so the subframe is hard-mounted to the chassis, and then there is a poly mount on the engine arms?

[raceablestreetcar]

Ooo looks nice!
What kind of isolation will you be using between the engine and the chassis?

Not that I have any skin in the game, but using an OEM part would allow an end user to choose between Poly and Rubber bushings depending on NVH and stiffness requirements.

Thanks! Right now I have a universal poly bolt through mount. There are options for different durometer ratings of the poly, but no rubber option. There is a poly option that is very similar in stiffness to an OEM rubber mount. I chose this mounting solution as it is cost effective, and easier to manufacture than using an OEM style mount.

[Panici]

Ooo looks nice!
What kind of isolation will you be using between the engine and the chassis?

Not that I have any skin in the game, but using an OEM part would allow an end user to choose between Poly and Rubber bushings depending on NVH and stiffness requirements.

[raceablestreetcar]

Some recent progress on the E30 build. Trying something completely different with the front subframe/suspension. Working through some suspension analysis currently to see if changing to a more traditional A-Arm will be beneficial. Trying to determine an accurate way to see the torsional stiffness changes between this design and the stock crossmember. Not sold on this design but the math will dictate where I go from here. With this system, it will also allow for a full drop in S65 swap with very minimal changes to the unibody. For those of you wondering why I don't just tube chassis the car and go to an SLA style suspension: the point of this project is to keep the unibody as stock as possible so other people can do this swap in the future without the headache of figuring it out themselves. I keep my Instagram the most up to date if you are interested in following along @rc3technologies

[raceablestreetcar]

Sounds quite involved. Thanks for the details.
Hopefully the technology will improve as it goes mainstream and the need for spray/dots will go away.

There are scanners that don't need the spray or dots, but they come with a hefty price tag, close to 6 figures.

[Panici]

Sounds quite involved. Thanks for the details.
Hopefully the technology will improve as it goes mainstream and the need for spray/dots will go away.

[raceablestreetcar]

Neat! Following for updates.

Just curious, why is it so expensive to scan something? Are you renting the hardware?
Or are you just adding up the time/effort involved to put the car on a rotisserie and then scan?

Scanning in itself is an expensive endeavor as the technology for commercial grade scanning is not cheap, therefore making the hourly rate to provide it as a service expensive. Yes you could buy a cheaper consumer grade scanner but then you are easily spending 4-5x the time scanning and it does not give nearly the detail of a industrial grade scanner. In the case of scanning an entire car, the price is largely due to the amount of time it takes to prepare for the scan (target dots placed if needed, scanning spray applied to glossy surfaces, etc), the time of the scanning itself, and then the time to process said scans and add usable geometry as a scan is just a mesh of points in 3D, it is not an actual CAD entity. The price listed above is based roughly on the thought that the entire process would take around 20 hours. If someone wanted more detail or the scans converted to CAD, then the amount of time needed would go up significantly. It does not include the time to strip the car and put it on a rotisserie.

[Panici]

Neat! Following for updates.

Just curious, why is it so expensive to scan something? Are you renting the hardware?
Or are you just adding up the time/effort involved to put the car on a rotisserie and then scan?

[ehrawn]

Well that’s a fun toy…and hopefully a sign of future aftermarket restoration parts support.

[TobyB]

Nice- and thanks for explaining the (huge) difference between a scan and a drawing....

Hopefully people will eventually stop running 11 degrees of castor making their cars handle worse.

now, now- for a real race car, running a lot of caster is a legitimate way
to make a crappy MacPherson suspension have some camber gain where you need it...

t

[raceablestreetcar]

Rather than contact you and make this some sort of secret discussion, I am going to pose my request out in the open: is there any chance you can 3D scan an entire E30 unibody? If yes, what is the total cost involved in doing this?

Eventually (I wager 15-20 years from now), we’re probably going to need it to 3D print new shells for projects. A greater percentage of E30 unibodies will have succumbed to terminal rust issues by then.

From the images you posted we already have about 1/3 of the unibody scanned. Just need the remaining 2/3

Hey, the entire unibody is something I plan to do in the somewhat near future (this winter). Its about a $3000 job for the exterior of the unibody and then probably another $1000 or so for the interior. Since I'd like the scan for myself anyway, no one will see that cost, rather I would list the file, along with CAD primitives fitted to important features, on my store for around $400-500 (maybe cheaper). In order to be able to reproduce the unibody, it would have to be converted to proper CAD. Scan to CAD technology will probably improve in the near future, but right now it'd have to be done by brute force. The time involved in that would be immense.

[ZeKahr]

If there are any particular components that you would like scanned, please feel free to contact me and hopefully I can help. Cheers!

Rather than contact you and make this some sort of secret discussion, I am going to pose my request out in the open: is there any chance you can 3D scan an entire E30 unibody? If yes, what is the total cost involved in doing this?

Eventually (I wager 15-20 years from now), we’re probably going to need it to 3D print new shells for projects. A greater percentage of E30 unibodies will have succumbed to terminal rust issues by then.

From the images you posted we already have about 1/3 of the unibody scanned. Just need the remaining 2/3

[raceablestreetcar]

Interesting, Should I look forward to a well done powertrain swap, and an E30 that handles?

MRT has made great lead way in suspensions scans and geometry. Hopefully people will eventually stop running 11 degrees of castor making their cars handle worse.

Haha, I hope so!

I have looked into MRT and they make some awesome components. Since I have to make a new front subframe anyway, I figured it would be a good time to do a design study on the front suspension and see how much improvement there is in moving the k points around. I'll likely end up with tubular front control arms as I'll have to fabricate them to align with where I place the points, but MRT is my backup plan.

[moatilliatta]

Interesting, Should I look forward to a well done powertrain swap, and an E30 that handles?

MRT has made great lead way in suspensions scans and geometry. Hopefully people will eventually stop running 11 degrees of castor making their cars handle worse.