3.2 Turbo Build

[Coultl]

The more I think about it, it would be really cool to make a Speeduino based drop in solution for the SC. If you really tried to keep the budget in check it could be done for pretty cheap. Just managing fuel and leaving the ignition system alone would keep cost down. CIS works well but it doesn’t last forever and it would be nice to get rid of the restrictive air flow meter. I can’t imagine there would be much of a HP boost, but probably a little!

[mikedsilva]

Originally Posted by Coultl

The more I think about it, it would be really cool to make a Speeduino based drop in solution for the SC. If you really tried to keep the budget in check it could be done for pretty cheap. Just managing fuel and leaving the ignition system alone would keep cost down. CIS works well but it doesn’t last forever and it would be nice to get rid of the restrictive air flow meter. I can’t imagine there would be much of a HP boost, but probably a little!

The idea is probably so we can run a decent camshaft and not have to rely on a fuel metering plate. I have tried bigger cams with CIS, and at idle and low rpm, with the overlap it can make the plate flutter.. which will alter the fuel delivery continuously.

My thoughts were, an airbox that disposes of the original airbox, and which can adapt a throttle body with standalone ecu OR a holley sniper. I've run a sniper on the engine stand and it seems to work fine. There are others who are running them in 914 and work well.

ignition can be taken care of by the original distributor and CDI.

If you went standalone, you could get fuel rails and injector adaptors from BITZ.

Someone made this manifold to run a holley carb and a turbo: i bought the intakes but not sure how I would go to get this replicated.
https://youtube.com/shorts/IkXNI71DzGo?si=EwuPdlZLQ9bf-6Pf

And here it is running (this had a BIG camshaft).
https://youtu.be/rLlUsFeiOVw?si=XJMg14Jgdiu4xf6s

[kamaro]

Originally Posted by Coultl

The more I think about it, it would be really cool to make a Speeduino based drop in solution for the SC. If you really tried to keep the budget in check it could be done for pretty cheap. Just managing fuel and leaving the ignition system alone would keep cost down. CIS works well but it doesn’t last forever and it would be nice to get rid of the restrictive air flow meter. I can’t imagine there would be much of a HP boost, but probably a little!

I have been fiddling with different stand alone ECUs with my 930 during the past few years and I will tell you that this industry has come to a point where its almost a plug-n-play to convert any internal combustion engine to the most advanced ECU technology. What you need to do is basically 3 things, injectors, ignitions, and sensors. The cleanest and most user-friendly setup I have ever done is to have a DBW, that makes your engine very clean and neat. I have come across an ECU called ECU Master EMU Black, and that will support EVERYTHING that any 2025 engine have, DBW, closed loop fueling, Knock control, traction control .. etc, and all that for just $1100, add $300 for a set of generic DBW throttle and pedal, and another $1500 for injectors, fuel lines, ignition, sensors .. etc and you will end up with a very modern and state of the art engine control for under $3000 USD.

[mikedsilva]

Originally Posted by kamaro

I have been fiddling with different stand alone ECUs with my 930 during the past few years and I will tell you that this industry has come to a point where its almost a plug-n-play to convert any internal combustion engine to the most advanced ECU technology. What you need to do is basically 3 things, injectors, ignitions, and sensors. The cleanest and most user-friendly setup I have ever done is to have a DBW, that makes your engine very clean and neat. I have come across an ECU called ECU Master EMU Black, and that will support EVERYTHING that any 2025 engine have, DBW, closed loop fueling, Knock control, traction control .. etc, and all that for just $1100, add $300 for a set of generic DBW throttle and pedal, and another $1500 for injectors, fuel lines, ignition, sensors .. etc and you will end up with a very modern and state of the art engine control for under $3000 USD.

Yes, I'm using an emu black... compared to motec, link, haltech, emtron etc.. it is "cheap"... and has everything on board.. no more extra modules or licences etc..

[LukasM]

Originally Posted by Coultl

Finally finished the manifold 3D print in PPA CF. Total print time was 150 hours, about $300 worth of fancy plastic, and the total weight is about 7.5 pounds. It is stout!

I ended up needing to reprint one section. Thankfully I realized right away that the prints shrink in the z axis by 0.5%. It’s a small amount but it would add up to 2mm across the manifold.

Next up is bonding it together and then finishing and painting it. The intercooler ‘cartridge’ is all designed and now I need to order the 3D printed aluminum parts.

I’m a little worried about the size of the Intercooler cores. They just feel small but they should be good for 500hp (~150hp more than I’ll run). I’ll only really know how they perform when the car is on the road…

This is really super cool, that you designed and 3D printed your own intake manifold at home! This was unthinkable just a few years ago when Stratasys kept the industry locked up with their patents.

Which PPA did you end up using, and how are you going to seal it up? Is the nylon glue going to be enough or did you design the interlocking pieces to use some form of gaskets?

Following closely as you are blazing this trail, as a fellow printing nerd.

[Coultl]

Thanks! I used the "Siraya Tech Fibreheart PPA-CF Core" filament. It has the carbon concentrated in core so the layer bonder is improved. I think this is the strongest PPA right now and it's pretty cheap too.

The goal with the bonded seams was to have the glue in shear as much as possible. The two halves of the main body have a huge overlapping joint and should be crazy strong. The runner to main body joints incorporate tabs that go across the bonded joint. This gives me some good shear surface for the glue, but honestly, the flat faces of the joint would probably be strong enough.

I will share photos of it being glued together. I first need to print TPU scrapers that I will pull through the runners to clear up and glue the oozes inside the runner. It would be impossible to remove once cured.

[Coultl]

Sharing an intermediate’ update. Not too much newness but some progress.

The manifold is coming together with brass inserts and mounting of the MAP sensor and IAT sensor. The IAT is from an Audi 1.8T…a good sensor.

Also, after three tries I finally successfully printed the back cover. This one is tricky bc there’s a lot of support material that was impossible to remove on my first tries. Even the Bambu PA support material which is made for this was impossible to remove. I ended up using ASA on the support interface and it worked perfectly. A huge unlock for printing in nylon.

The throttle body brass inserts mount from the back. They are crazy strong, but this is a spot where I wanted to make sure they couldn’t pull out.

[Coultl]

More photos.

[decisive1]

Looking very nice. Is that a 74mm throttle body?

[Coultl]

Yes, it's a 74mm. Way bigger than I need but also very cheap...

[Tippy]

This is very cool and I have been wanting to design a Nylon intake myself.

Great work!

Here are the ITB adapters I designed years ago that were physically machined in China from a fellow member.

Looks like you have the same interface:

[Coultl]

Nice! I reverse engineered mine from a 3D scan of the stock manifold. The injector angle was a tricky part.

A bit of an update. I decided I should do a test torque of the runners before gluing everything together. The result, total failure. Crapola...

I torqued them early on but this time I used the proper plastic intake spacers. I think what happens is that the intake spacer is soft and deforms under the 3,000 lbs of clamping force for each of the mounting bolts. The compliance of the spacer transfers a huge amount of load across the full face rather than just below the bolts. The plastic flange has basically zero flex so it cracks.

The plastic flange would work on a metal surface but it's not going to work on the soft plastic spacer.

So...the plan is to have the lower sections 3D printed from Aluminum and then bond them to the nylon intake. It's an extra $350 and a little annoying.

I think I'll take a break from this and get the turbo plumbing in order.

[Tippy]

Originally Posted by Coultl

Nice! I reverse engineered mine from a 3D scan of the stock manifold. The injector angle was a tricky part.

Yes, the injector angle ate my lunch. I was just learning CAD, so it took me weeks of messing around before it was right and mimicked the Carrera 3.2 perfectly.

[j_green]

A bit of an update. I decided I should do a test torque of the runners before gluing everything together. The result, total failure. Crapola...

This is a super cool project!

I hit the same point when doing my 3.0 EFI conversion, the plastic adapters just weren't up to it so had them 3D printed in aluminum. Pretty easy for my application since I was already using the 964 manifold and factory gaskets so I didn't have to make many design changes to just bolt on the new ones.

The amount of material does significantly impact the price though, so for mine I found I could get away with a much thinner flange overall with just adding more thickness at the bolt hole with a healthy chamfer for support.

[Coultl]

Beautiful part. Love it. My adapters are much heavier weight unfortunately bc I designed them to be plastic. My CAD model is such a mess and Fusion 360 is quite weak in terms of parametric referencing. Changing the flanges (the first features in the model) isn't an option anymore!

[j_green]

Yeah I use Fusion too so I feel your pain, keeping things neatly parametric is pretty much impossible for anything other than super basic parts. But yeah, juice probably isn't worth the squeeze on that.

I'll be following along though, what you've got so far is super exciting!