Custom Fab Parts? (3D Printer, CNC Mill, etc)
 

Man, who does this kid think he is? First he wants to swap a manual Boxster S engine into an automatic base Boxster. Now he wants to make custom parts for a car he doesn't even own?

Heh.

Anyways, so I tried looking around without that much luck. There were the occasional spurts of almost what I was looking for, but not quite.

What parts do you think would be great to make custom?

Off the top of my head I thought intake parts. You could easily 3D Print it, with NylonX or similar (ABS Could work, anything with better than normal heat tolerance), for super cheap (ABS Costs something like $0.40 a gram, so a part similar to Pedro's Techno-Torque would cost way under $259 (try $2.59). And while it may not be super optimized, it would be cheap, and would work. And with the brief research on intake results and findings I've done on this forum, instead of having super optimized geometry, you just open up the diameter and it'll let just as much air in correct? Though, not too much as then the DME can't adjust for it and you'll forever run lean...?

Anyways, it doesn't stop at 3D printing, you can CNC Mill parts, hell, you could make lightweight aluminum everything for the engine, valves, pistons, shafts, etc (I probably will not be doing that till I understand what the hell even goes on under there though).

But yeah, I wasn't able to find much on this topic, perhaps for good reason?

What are your guy's thoughts and ideas for what someone could do with access to a 3D Printer and CNC Mill? If anything produced becomes a success, we could be looking at a new era of 3D printed Boxster parts! :P

Someone on here was offering to print parts a short while ago. I think 986 does a lot of cnc work. I used to have an old gf that was a cnc prototype designer. She could make about anything if you could explain what you needed. Wasn't much of a gf long gone

Sheesh :P

Well if someone’s done it then I can do it. Just gotta find out what parts to do. Do you think the intake plenum is a good one? Or what about the pipe that connects the air box to the throttle body? Could make a larger diameter one to house a larger throttle body and let more air in.

There’s gotta be plenty of parts that could be improved upon.

Member Ben (not MrBen) made quite remarkable work on the plenum add-ons already however he haven't touched the outer/larger air intake.

That's one of those thing that I trust can't/cannot be 3D printed and can only be achieved using injection molding processes, if the idea behind is to improve what has been engineered by Porsche. Reason for that is inner-wall surface roughness and how this influence air velocity (i.e. turbulent env and dyn pressures).

If you have means to validate the flow and manually polish the interior of that part then this could potentially be a nice add-on to Ben's plenum mod! Are you familiar with CFD modeling?

One add-on in the fluid domain that comes to mind is this part. It does not add that 700 HP however it definitely helps in scooping a tad bit more air to the intake at both low'er and high'er speed, and helps cooling engine compartment (opposite side). I believe this could be a nice 3D printed item; not requiring a whole lot of engineering (cfd modeling-wise), easy to surface finish, "and functional", etc.

Apologies for the low resolution picture. If you need more just ask and I'll see what I can do for you.

http://986forum.com/forums/uploads02/011579599920.jpg

http://986forum.com/forums/uploads02...1579601258.jpg

I am currently not familiar with CFD modeling but I have access to the tools and am a quick learner.

This can definitely be done. When I get my hands on a Boxster I’ll take out the intake assembly and model it in some CFD software (AutoDesk’s Flow perhaps?).

From there I can try to model a new intake assembly, starting all the way at the side scoops like you pictured. I see multiple places that could be improved design wise, actual performance gain wise, there may not be much. But this is more of a fun project than anything.

As far as the internal smoothness, if printing in ABS, you are able to wipe it down with Acetone to smooth it down quite a bit and then spraying it with a sealant or clear coat will improve the surface even further. I can research more on this.

Saying you have custom parts in your car, to me, is pretty cool, especially when you can say you modeled and produced them yourself :)

And if it turns to be a success, I would be happy to produce these for others.

Thanks!

Sounds good, you seem to be on the right track! No exp with Autodesk's but pretty sure they use quality solvers, hopefully can converge medium to large flow models like those you plan, dunno. You should be good to go on that front, I'm guessing.

You are correct about the light performance gains. Although still some, the response and experience will/should be at a whole new level. That would be the added value to a retrofit like this (imho).

Step 1: Get a Boxster?! ;)

I’m trying, I promise!

My 2 cents on the 986 intake system . My 3.2 S from the factory made 250 hp at the crank a same year 3.4 996 made 300 . Some of the increase in the 996 is the bump in displacement but there have been tons of discussions saying the real increase is due to exhaust and intake .

Plenty of easy exhaust options out there but intake is a little harder . Install a 987 air box that helps with flow . Add a larger throttle body that also helps . Add a 996 intake manifold another jump in flow , but to do this additional mounting holes have to be drilled in the 986 heads . A lot of folks don't want to do that . So if someone had a 986 manifold and a 996 manifold sitting on a bench side by side they could be measured and scanned/modeled for 3D printing . If a 996 sized manifold could be made but with the 986 mounting foot print now you might have something .

I am not smart enough to know about port matching or anything else , but if 5-10 hp could be picked up and it's a straight bolt on it could be a winner .

Ah, 3D analysis. Now we’re onto something.

So when I do get my Boxster, the exhaust has to be mostly left alone, as I am one of the many sad Californians :( I’ll likely remove the mufflers or replace them for weight reduction, but I can’t touch the catted headers.

But intake parts are definitely manageable, and I’m hoping to get to poke around my engine when I do get it. Headers weren’t on my list yet as I thought they were in direct contact with the engine which is a big no no since the engine gets hot! If I was able to find out how hot exactly and a printing material that could withstand that heat, then I would be all for it.

I need to get my hands on most of these parts before I can design and model. That’s the main problem here. Maybe I should ask if anyone in Northern California has a boxster sitting around I could poke at.

But I definitely hear you. Thanks for the ideas.

Also I’m designing for the base 2.5L Boxster. Can I even fit 996 style headers?

Some bad news. I downloaded AutoDesk's Flow Design software only to realize it wasn't powerful enough, didn't do what I needed, and was 6 years old.

Some good news. I was able to get access to AutoDesk's CFD Ultimate software which costs over 7x as much as AutoDesk's AutoCAD ($1620 vs $11600 a year) as I am a student. Pretty cool I must say. This software is exponentially more powerful than Flow and will 100% do what I need

I'm going to teach myself fluid dynamics which I think requires at least 5 years of schooling to get a degree in. Wish me luck!

I do CNC and 3D printing. I personally use Solidworks for all my modelling, though my design language is very functional and industrial, i.e. lots of hard angles and such. Nothing very pretty.

As far as the 3D printing, I wouldn't print anything for the engine bay. Partially because most printers that most people have access to wouldn't be able to print anything that could stand up to the heat. Because 3D printers print in layers, plastics that might not necessarily melt will instead start to delaminate. There are ways you can print something then treat it so it wouldn't delaminate, but at that point, you're probably better off just buying an injection-molded piece. The only thing I've printed so far that I liked was a series of shift knobs, but they ended up feeling too light, so I stuck with my big metal ball one.

For the CNC, yeah, I'm sure there's a million things that could be made for the 986. I use a small CNC mill at work, but most of the things I want to make for my 986, I would need a CNC lathe for.
Not to mention, half the time, there's not much to be improved on the Porsche parts without a ton of R&D or some expensive material, i.e. titanium. (I'd kill for a few bars of titanium at a not-insane price.)

Though if anyone has any ideas, let me know and I can see what I can do!

Also, Russ, if you want an exhaust, I have a full one that came off my car. It's stainless, and fit pretty well! Mufflers were on the car when I got it, and I have headers and midpipes off ebay if you want some straight pipe madness. It sounded great. I'll sell it to you for super cheap to get it out of my shed.

Hmm. Starting to think I’m a bit over my head. At first I couldn’t even get CFD to open a simple C pipe drawing. Then when u finally did, I tried to resize the window and it has disappeared. Permanently. All the missing window guides were no help. I reinstalled and repaired the program. The whole deal. Nothing. Ugh. When the software costs $12000/yr, I expect it to not have any hiccups. This is dumb.