Hey_Allen

Hopefully you're considering having it printed in actual metal, not a plastic print?
3D printable plastics are almost all thermo-plastics, and the majority of those have a melting temperature well below what I'd feel comfortable using in the engine bay of a car.

That said, if you're having quotes in the Few hundred range for a sintered metal print I would be interested in knowing what vendor you're taking to, as the one my employer used for a metal print was ~$130 for a 1"x3"x1/4" part.


As to the throttle body needing the larger opening, I was considering one of the GM style ones with the wider oval inlet. I think I could cut back the rear of a stock plenum and weld a flange directly in line.

Ben006

No I don’t plan to make it out of sintered metal, but nylon.
I’ve made plenty of plenums for 996 and 986 out of sintered nylon.
The majority of modern vehicules have nylon intakes.
An intake doesn’t get as hot as other engine block components and is cooled by intake air circulating through.
on my 986, which has a very confined engine bay, I measured a maximum of 70 degree celsius after an hour of hot Florida summer driving.
I’m not worrying about this choice of material at all
The main problem is that it’s not glass filled nylon, and it’s not as stiff when hot and not as dimensionaly stable, but with the right design this is not a problem.

If I ever need to make more than one, I’ll consider other options, but unlikely to be aluminum.

An oval throttle body won’t fitt the stock plenum. Mine isn’t that wide and it’s already too wide, so even wider won’t help :/

Ben.

Ben006

Hello !

So... As planned , I won the 500€ award for 3D printed parts with my 928 intake plenum project

I started to order most of the parts too.
I've got an Innovate MTX-L wideband O2 sensor (will need to find a good place to fit it).
The coils, the CKP sensor, and an adjustable fuel pressure regulator !
I received the fuel rail too !

So, parts are coming, and the project should really take off soon

jbrob007

Ben, Checking in on your project and gotta say it looks to be one helluva undertaking... amazing. Keep at it !!

Joel

Hey_Allen

I'm going to have to play with Nylon once my new printer is built.
Not having an enclosure on the current printer, Nylon isn't an option, and even ABS is a pain.

Keep us informed, this is looking promising!

karl ruiter

Another option might be to print it in wax and then sand cast.

Ben006

Thank you ! It's a long road until I can fire it, but I'll get to it

I have a deskot printer at home capable of printing nylon and carbon fibers filled nylon, but for this kind of parts, I'll subcontract to a better equiped company !
They will use HP's Jetfusion printer, the parts have very desirable characteristics ! Heat resistant up to 175°C, very strong, very accurate and with a very nice finish that will not need any hand finishing like I use to do with SLS nylon parts.

It is an option, though for me that's extra steps to a less desirable part. Aluminum is not an ideal material for an intake.I also have no experience with casting, and no time to practice :/ That's a skill I've always wanted to learn though !
So, for this time, I'll stick with what I know

I received the blank fuel rail, and the wideband sensor

I'll have to make a video for the award, I'll post it here so you can enjoy my good old french accent


Ben

Shawn Stanford

Get the Chevrolet alternator.

Ben006

Thanks for the tip, can you give me more info on it ?
Which model/year to get ?

Thanks

Shawn Stanford

Here's a thread about it: https://rennlist.com/forums/928-foru...onversion.html

I got my second one (I broke the first by being dumb) from a local auto electric shop. He set up the pigtail and swapped the pulley and it only cost $65 out the door.

Ben006

Thanks ! That's nice !


I'll be getting one soon


They released the article about the 928 intake ! Though, it's in italian, and I don't read italian ahah !

https://www.3dprintingcreative.it/we...pEFFL_uCCKGOQ4

Hey_Allen

Google Translate says:
https://translate.google.com/transla...pEFFL_uCCKGOQ4

GT6ixer

Congrats on winning that grant Ben. Cool stuff! Did they tell you when they would be able to finish the part? I'll be very interested to see how the finished part looks. Did you have a chance to print it out in say PLA with your home printer to make sure it fit they way you wanted it to? Or is Weerg offering to print multiple iterations as you refine the design? Not sure how many prints 500 Euros would cover but a part of that size I'd guess just one.

What do you know about the materials the HP printers will be using? I've only read a little and it sound like a form of thermoplastic, but that could be a thousand things.

Congrats again on winning the grant and it's even cooler that you decided to do it with a 928 part! Love that.

GT6ixer

What printer are you building? I have a Prusa i3 MK3 and have made quite a few parts out of nylon without an enclosure. Warping with nylon in my experience is no where near as bad as with ABS. The key is getting the nylon completely dry before you print. I usually pull off about twice the length of filament I need and put in in the oven at 180°F overnight. I then print really slow (10-20 mm/s). I've just about given up using ABS anymore because of warping issues. I just got a spool of PETG last week and am going to try that out for the first time. Could be a nice ABS alternative.

Ben006

Thanks !
The part won't take that long to make, once I place the order it'll take approximately a week to receive it My home printer is too small for it, but I know it'll fit, the complexity here is not making it fit, but making it durable ! With the grant, I'll probably only print one... It's a big part, so it's expensive :/ Though, I have a little something on my mind that could save me $$ on the printing price, and still make a better part ! But I have to check with another guy if he can do it first

Here is PA12's datasheet : https://www.weerg.com/en/index.php?c...d_attachment=2
It's close to what automakers use, but with the glass filling, which makes it a little softer when hot. That can be addressed with reinforcements.

I can't wait to have it done and finally hold it in my hands !

I worked on the car a bit las weekend !
I'm going to get a lift next week, that way I'll be able to start on the suspensions stuff ! (Though, I have to work on the Boxster first, it's getting new coilovers and new control arms).
I made a bet with my friends... I have to make it run for Porsche Paradise (Paradis Porsche) in October in France ! It's the biggest Porsche gathering here.

Here is where I am :
Got the coil packs :

I'll use VW wires too, they are the correct length and at 22$ for 4, way cheaper than 928 wires !

I made and fitted all the intake plugs !


I'll ask my shop foreman tomorrow (today's a holyday) if I can borrow (and never return of course) some wheel cleaner to clean the greasy engine bay !

I stopped there :


One thing I might change here is the oil filler... It's in the way of the intake, and it doesn't look good...
I don't think it communicates here :

If I cut it out it shouldn't leave a hole, and I'll be able to use my Jeep air oil separator which is a bit bigger and should work even better with a similar design.
We'll see !

I'm selling the whole ignition system : distributor, wires, coil... what price do you guys think would be fair ?