openinverter forum

Hi All,
So i'm going to try to document more of this project than I did of my Rx-8 Build.
The 996 has been a dream car of mine for a long time so when I saw one with no engine or gearbox, i had to have it. The's called 'dusty'.

My plan is:
- Tesla Model s/x small drive unit (not model 3 as you will see in pics later)
- 50 kwh CATL modules from the stellantis models
- Mitsubishi Outlander / MG 6wk charger (already have one)
- Not sure which DC /DC if I use the MG charger. Suggestions?

I'm planning to outsource much of the fabrication so this won't be a quick build, but that'll give me enough time to finish the rx-8 hopefully!

Here are some of our efforts in scanning the underside of the car, and some attempts to fit the model 3 rear motor (in its native orientation).

Long story short it won't fit without a lot of chassis mods, and there are no solutions which enable it to be run in reverse currently, so out of the question.

The Tesla, SDU, by contrast looks like it might fit with little / no mods.

Check out the 3D render...

https://myhub.autodesk360.com/ue2feb09d ... 740fdfa2f2

Awesome! Man I've been a Porsche fan since I was 14. A 996 is my dream car, really hope to own one some day. You made a great find!

Gen 1 Volt/Ampera dc/dc is reasonably compact, powerful and easy to control

Would you mind sharing your scan for download so I can have a play with it in Fusion 360? That Tesla SDU still looks very tight in that subframe.

tom91 wrote: ↑Fri Jul 05, 2024 4:07 pm Would you mind sharing your scan for download so I can have a play with it in Fusion 360? That Tesla SDU still looks very tight in that subframe.

Yep I'll ask James (who did the scan) to make it public

In terms of proximity to the sub frame, yes this fouls on the sub frame mounting points left and right, but it can be raised quite a bit. I took a photo of the underneath to illustrate -- the large coolant lines above the current motor location can be moved / removed, allowing it to be raised and tilted forward. I'm hopeful I'll be able to make it fit with minimal / no sub frame modification.

As promised, the scan of the underside of the 911:
https://grabcad.com/library/porsche-911 ... gine-bay-1

Zieg wrote: ↑Fri Jul 05, 2024 3:57 pm Awesome! Man I've been a Porsche fan since I was 14. A 996 is my dream car, really hope to own one some day. You made a great find!

Gen 1 Volt/Ampera dc/dc is reasonably compact, powerful and easy to control

I wouldn’t use this DCDC again. Too big and no IP.

This project is going to be great. Looking forward to following the progress.

I would say a Tesla RDU wont really work without massive changes to the aluminium subframe members which I would steer clear of. Also massive lack of clearance around it to the subframe even if you remove the mounting points for the rear crossmember.
Possibly a Front Drive Unit will work given it is angled back. I do not have a reliable model to position in the scan. EDIT found one https://grabcad.com/library/tesla-front ... -3d-scan-1

Here is what I taught with a Front Drive Unit, it is tight to the body above the subframe but alot better as you are in a wider subframe section.
You would want to rotate the drive unit down from having the cooler horizontal, till you get clearance.

Thanks for the advice Tom!

I've organised to buy a known working front motor with the OI board already installed from another project in the classified section. I'll report back when that's test fit in the car

My fusion skills are very weak, but i've been doing some playing with the models and it looks like it might fit...just...

https://a360.co/4cCQCeH

If you have two mesh files, meshmixer is much faster for just trying to orient them to test fitment.
Fusion struggles with detailed meshes.

Great suggestion on the front drive unit! Seems like it’s pretty feasible.

Mitchy wrote: ↑Thu Jul 11, 2024 11:15 pm If you have two mesh files, meshmixer is much faster for just trying to orient them to test fitment.
Fusion struggles with detailed meshes.

I do all my CAD work in Solidworks and I end up using Blender to orient the scans where I want them / to the origin before importing them into Solidworks because Blender is soooo much better at it. Just mentioning another good tool that you might find useful.

I tried blender but i couldn't get my head around it! Maybe I'll try again because it did perform very well with the scans loaded.

steveknox wrote: ↑Fri Jul 12, 2024 7:10 am I tried blender but i couldn't get my head around it! Maybe I'll try again because it did perform very well with the scans loaded.

I had to pause the YouTube video after each step to learn how to use blender for this and do it a bunch of times. I still end up pulling up this video occasionally for the keyboard shortcuts still.
As for origin, if you are doing automotive cad look up ISO 8855 and SAE J670e, I use iso 8855. This way it's oriented properly for say suspension analysis but check the tool you plan to use for which method(s) it's compatible with.

Yeah really useful video. I'm going to re-try to get both my objects aligned in Blender before bringing them again into CAD. Thanks!

Has anyone managed to create a surface model (not mesh) of the 996 engine bay?

I am working a similar project, but SolidWorks freezes up every time that I begin to convert the mesh to surface models.

FWIW, I am converting a 2003 996 using a Cascadia Motion IM-225 mated to the 996's G96 transmission. I had originally wanted to use a Tesla drive unit, but quickly realized the suspension will be in the way. The IM-225 will fit well, but I am doing some fun design work to get the motor to mate to the transmission. I would like to use a Solidworks surface model to design the motor&battery mounting to the chasis.

Thanks again for any help you can offer!

Well it's going to fit. There's no replacement for doing it for real so i got a friend to help test fit and plan some mounting strategies. There isn't a huge amount of space but there's enough, and plenty of options for mounting.

chris8382 wrote: ↑Sun Jul 21, 2024 1:52 am Has anyone managed to create a surface model (not mesh) of the 996 engine bay?

I am working a similar project, but SolidWorks freezes up every time that I begin to convert the mesh to surface models.

.... I would like to use a Solidworks surface model to design the motor&battery mounting to the chasis.

This should probably be it's own thread. If you start one, tag me.

Are you trying to do some FEA on cutting the firewall / body or something else that requires something besides a mesh?
If not the mesh should be plenty usable to do mock up. You can add studs, cylinders, planes, points, or other hybrid features to allow part manipulation, mating, etc.
You may also have to decimate the mesh if it has billions and billions of points. Solidworks does not handle lots of points well. Just do it with just that mesh file open.
And if needed, use blender to align the mesh. Search my username and blender for a video.

So I've been working mainly on my RX8 project but haven't forgotten the Porsche. I've been focusing on trying to design a frame which will require no body modifications.

Here's what I've come up with. Two parallel lengths of 60*30*5mm angle mounted on both subframe bolts and the rear hanging from where the original engine mounts once lived.

The rear mounting design will change to avoid using the threaded rod but for now it helps with adjustment, and this design was based on using the existing engine mounts which i subsequently decided against.

There will be two cross - beams (one pictured). The one next to the motor will house a motor mount and act as a front mount for the battery box which will bolt up into it. A similar cross beam at the back will be the rear battery box mount.

I've chosen to go with the ubiquitous stelantis 50kwh pack. This example came from a Citroen ec4. I picked it up for £1100 delivered. The lid is glued down so its a right pain to open.

Ive started mocking up the rear box, containing 12 of the 18 modules. The rear will also house the HVJB and charger, sitting above the battery.

The box will be raised into the car from the bottom, bolting to the cross beams pictured above.