Hi Chris, @Tygaboy
I like the taillight panel venting and think that would be a very cool place for the intake. I like the design with the slanted openings- did you consider trying to match the sail panel angles for the openings? Just spitballing while looking at it. Not sure about the trunk lid vents- For me, with the front vents, which I love, the rear lid goes to far.

Looking Good Chris!

Food for thought: Instead of levered vents
What about a "Torpedo Outlet"?!?
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Could be a design play from the shape of the front fender... much like this first submarine pic
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could have a vent "Butterfly" like this second sub pic
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By "Torpedo Outlet" I mean like what you see on a submarine only facing backwards
Even crazier... tie the torpedo vent to the gas pedal so that it opens upon acceleration.
Like the butterfly on a blower...

Early morning design impressions with my second cup of coffee!
Cheers,
Cass

Chris
Now that you have opened up your forum to idjits like myself, with more creativity than sense, I have two suggestions. First, for the intake. Use the rear of the trunk, where you already have two options, and run the intake to an air filter that is attached to your rear valence work. From the back of the car, the only part of the intake that is visible would be black mesh covering the filter.

Second, obviously you are very anxious to cut on the trunk lid. What about modifying the trunk lid to act as a downforce spoiler? NO…..not the whole trunk lid, although that would look awesome, but just the rear part of the trunk lid. You probably have the electronics to tell a spoiler to open at a specific speed.

I always thought Armando did a nice job on integrating this transmission cooler in the back-panel - food for thought:

https://pbase.com/9146gt/the9146gt_901_916_...and_fabrication

You may need to call your 914 the VENTura model.

Back to the wiring since I figured I should focus on things that'll get the car back on the road...

Out with the old, in with the new: First thing is to mount the new components. The ECU Master power management unit (PMU) you see here replaces:
- the Arduino "magic box"
- 8 relays needed by the Arduino
- the wireless turn signal management unit
- all but a few of the fuses and relays

I also upgraded the Raptor wireless unit to the smaller "GP" version in the pic.

The ECU aside, what's pictured are the only other electronic components needed to operate the car. Much tidier, if I do say so.

Next up: wiring!

I swear I'm working on the wiring! But a main component arrived for the other intake design I'm planning. Aluminum CNC 2 x 3" to 4" merge. This attaches to the throttle body and will then have symmetric intake tubes running to a matched set of air boxes/cleaners - one on each side of the engine.

Ready for the intake tube routing!

Not even I can keep up with what's going on with this build!
Headers and exhaust are back from ceramic coating. This color is "titanium' - at least at the place I used. It's a bit less gold than the Ceracote I had on the exhaust before and being a bit more subtle, I prefer it.

And I think I'm going to pull cold air through the rear panel vs. venting the trunk lid. At least for now, anyway. On to building an appropriate air box.

Looking amazing! I agree with your thoughts on not putting vents in the deck lid.

Hmm. Well at least you're in good company...

This was the first iteration - much improved later on (second pic) but this gives you an idea. Yours will be infinitely better, I know, but I was building this purely for performance.

For those that might think I am a bit hard on Chris - we are ok; he has thick skin.

Cracker



First attempt...
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Final iteration...
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We be friends...
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Isn't the air space immediately behind the car turbulent and/or low pressure?

I won't post on Chris's build thread anymore on this but the answer is yes, you are correct. These two men, from Porsche Motorsport were in North America for meetings and at Barber Motorsports Park while I was running. They came up and asked if they could look the Teener over and take pictures - I obliged and we ended up having a good long conversation about the 914 platform. One thing that puzzled them was the intake design (appropriately included in the picture below) - they marveled at how fast the car accelerated - it didn't make sense to them. Many other knowledgeable "racers" have questioned my intake design - bottom line - it works - period. To make matters even more confusing for folks - my oil cooler intake was captured from the roof and onto the intake - people thought my intake was exhaust and oil cooler was an intake. Fun.

I look forward to seeing what Chris comes up with - at least the first 10 or so variations... Enough of my old build - Chris, get this car finished!!!

Cracker



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Do you have a picture gallery of your car somewhere? i would really love to look at whatever you have!

More input from Tony @cracker - and I don't know why I didn't even try it earlier: Run everything to the right side. He suggested building the air box inside the fender, behind the rear wheel so the intake tube would "end" inside the trunk.
I'm noodling on that part but I think the "go right" design is a keeper.
I'll likely cut/reweld the intake tube to get it to exactly match the angles of the exhaust.

And no, this will never end!

And to complicate matters, I just watched a PAIR (not a set, a PAIR!) of 16 x 8 Fuchs sell for $4100 on Bring a Trailer. I thought that was insane so went to the Fuchs site to see what brand new ones cost. $948.72 each.

What am I not understanding? I guess maybe date codes are everything so some folks.

Anyway, the REAL problem is I see this banner on the site. I think I need a set just like this in 8s and 9s!

I'll bite Chris...those wheels would look absolutely killer with a blue car (someday; year; or decade)!

Cracker

You gotta take cracker a little at a time. It's like a low carb diet.

Not accurate, Rand...you take "cracker" with good cheese and wine and enjoy the moment(s).

The cheese is boost.
I don't whine.
I will enjoy the moment.

Given all the "non-914" stuff I'm up to with this build, I'm sure some of you think I'm a bit twisted. Well so is this next version of the intake! Thanks, I'm here all week...

Just playing with the untrimmed tubing components and it's only on the one side but this shows the basic idea: get the tubes pointed forward and connected to twin air boxes, one on each side, just outboard of the heads. Note that rubber connector is just helping position things and those tubes will likely get welded - pending proof I can get the final part in/out of the car! But so far, it looks like it'll work.

Quite a ways to go still, clearly. Plus, this intake means I'll need to build a different exhaust that just runs down and back. But this set up gets me all sorts of room to build a removable trunk floor/sealed carrier box so if I really wanted, I could transport a long weekend's worth of luggage.

You wouldn't have these issues with ITB's.

He's heard this before...

Cracker

Sweet

More not even remotely 914 stuff!
The PMU (power management unit) and wireless receiver harnesses are ready to go in the car.
I opted to go with the PMU vendor's flying lead harness so most of that wiring will be trimmed away as it's only about 4' from the PMU to the connection point for all but a few of them.

... and the exhaust is off...

And so it begins... again.

I will say, I'm getting pretty comfortable with all things wiring. Still lots to learn but I'm at the point where I really enjoy doing this sort of work. It appeals to my sense of order - at least trying to get it in some sort of order!

I see the most important tool of the day besides wire strippers...
The "Red Taped Chest Rest"

A few of you asked that I post details about the wiring work. OK, here's some fun stuff:
I want to add reliability to everything - and in the case of wiring, that means sealing every connection that I can. Today was my first go at potting a factory sensor.
This is the transmission reverse light sensor from the Boxster 6-speed. Normally, it has a rather standard plug-in connector. I opted to make it a fully sealed sensor with a short pig tail that terminates with a Deutsch DT series connector.

First, tin a couple suitable wires - these are 20 AWG conductors. Color doesn't matter as they'll be fully sheathed in Raychem DR25 heat shrink. Plus, this sensor is just an "on/off" switch so it doesn't matter which terminal gets power. When that sort of thing matters, I'll be paying attention and testing each connection before pinning the connector...

Anyway. Next, tin the terminals in the sensor then solder the tinned end of the wires to a terminal. Note I'd folded the stripped wire back on itself before soldering so a bit of the insulated portion of the wire is already down in the body of the sensor. Even still, once the wires are soldered, you push a bit more of the wire into the sensor body to provide a bit more strain relief.

Here's that work all done.

Next, I slipped the heat shrink over the wires and set up a support contraption to keep the wire oriented as the potting epoxy cures.
This little portable, rubber jawed vice is just the ticket!

Then, it's potting time! I'm using a 3M product as it's readily available and I've had such good experiences with their other products.

That first pic: I found it's easier to pump the potting epoxy (gently!) into the syringe vs dispensing it onto a surface and using the syringe to suck it up.

Use the syringe and work around in all the cavities to carefully fill the sensor body with epoxy. Take your time and be sure to avoid creating any air pockets.

Once the sensor body is filled, gently slide the heat shrink down into the epoxy.

Be sure everything is aligned and secure!

Once the potting compound is cured, I'll fully shrink the heat shrink then add a heat shrink boot that goes over the plastic part of the sensor and seals to it and the heat shrink you see here. That makes for one seriously reliable sensor!

I plan to do the same thing with my tail light housings. Remember, I have no trunk floor and those tail light wires are exposed to whatever the tires may toss up at them.

Done! Fully booted at the sensor and ready to go back in. On to the rest of the rear lighting harness.

Not that I'm fast at anything but making the mods to this sensor was probably a couple hours. And I'm using the "inexpensive" Deutsch DT series connectors. The two pin connector kit I used here is about $7. A 6-pin DT is about $15. A 5-pin Deutsch AutoSport connector kit is ~$140. Yes, like 10x the cost.

So when you hear that costs for a full-on motorsports harnesses can get well past $20K, you'll know why!

Chris
About a year and a half ago, you recommended Deutsch connectors to me. And then I rewired a lot of my 914 using Deutsch connectors. Initially I was concerned about their durability but after many connects and disconnects, they have held up very well. Thanks for the tip.

I know...

I do recall a conversation regarding wiring in which you said, "I don't want motorsports level wiring in the car..." Just say'n...

Cracker

Well that’s a far better method than my hot glue gun option!

Very nice work as usual Chris!

Back to chassis harness wiring. I'm replacing all the screw terminal blocks with Deutsch connectors. Here's the stock 914 ignition switch connector sheathed in DR25, sealed at the connector with a short section of adhesive lined heat shrink. This is a product called Raychem ATUM, for those who might be interested.
This particular connector is a DTP series - the P standing for "power". These have far larger terminals that can each handle 25 amps.

Ignition harness done, tested and installed.
Note that all my large current loads are managed via the PMU so none of the "big stuff" (starter, alt, fuel pump, fans, lights, blower, wipers) pass through these wires.
Yep, over built for what it'll have to handle but I prefer under-stressed electrical systems!

The behind the dash layout is essentially complete. Part of the planning was to be sure that every section of the harness can be unplugged and pulled through anywhere it passes through the chassis - all without any drama.

The zip ties locate each branch point so once things are final, I can pull it all out, sheath and seal the entire thing and reinstall it. Nearly there with the front-of-chassis harnesses!

Nicely done--and smart strategy. My OCD approves!

Very nice! Love the brackets!

Love the wiring - nice demonstration of how to use connectors that are more appropriate than 1950's technology

@Superhawk996 - Oh, you want connectors? HERE'S a connector!

With the ECU moved to inside the cabin, I have to pass the engine harness through the firewall. Yes, THAT firewall. The one I made three different times. I've been laying awake at night thinking:
"Really? You're going to cut a hole in your firewall? You, the guy who changes his mind all the time..."

The answer is "Why yes. Yes I am!". But that means I need to be sure and fill that hole with something pretty cool. So I decided I'd use this. It's a Mil-Spec 61-pin, 1/4 turn quick disconnect bulkhead connector.
Disconnect it and the entire engine harness stays with the engine when the drive train needs to come out.

Yes, I cheaped out and went with a Mil-Spec vs. the Deutsch Autosport series (AS) model. And here's why:
The Deutsch AS version would have cost ~$450. Yep, for one connector.
While not that same ridiculously high level of quality, this mil-spec version is $185. Still not cheap but quite a savings - and most importantly, the quality and capability is still WAAAAAAY overkill for a street car.
All that said, I'll still be sweating when I cut that hole in the firewall...

A way-too-much-detail post about wiring:
I'm documenting to this level so that when I sell the car (which I will, at some point) there will be a ridiculous amount of supporting info about how and what I did re: the wiring - all of which will be completely sealed in sheathing and essentially unable to be "inspected"...

These are my first practice samples of open barrel crimps. The goal is no soldered joints anywhere in the car. Soldering turns stranded wire into solid wire and increases the chances of a vibration or stress-related failure.
While there are lots of examples of soldered joints not failing, I'm opting for open barrel crimps.
These first two are practice samples to be sure the crimp size works with the wires being spliced. Having the correct crimping tool make the crimp process simple.

The gray example is 16 ga, the green is 18 ga. If you think these wires look smaller than what you'd expect for those gauges, you'd be right. Read on, if you dare!

WARNING: FULL GEEK ALERT:
This is M22759/32 Tefzel wire. It's a lightweight, high temperature wire insulated with a single layer of cross-linked, modified ethylene-tetrafluoroethylene (ETFE) insulation. The insulation provides superior cut-\rough and abrasion resistance and where where high temperatures, smoke emissions, and flammability are a concern. It has a maximum temperature of +150°C and a voltage rating of 600V.

As I just mentioned, having the right crimp tool really helps. But doing these crimps in the car while ensuring the wires are correctly positioned in the crimp? Less easy! But I got them done.

The gray wire is the parking lights. The main feed from the PMU splits with one to the front park lights and one to the rears.
The green is right turn signal. Here, I have the main feed from the PMU, one to the front signal and one to the rear one to the rear. That 4th? It feeds the indicator light in the dash. And yes, I almost forgot that one. I had the other three in the crimp and I was just about to squeeze. Thankfully, I caught myself.

This pic is also a good example of the adhesive heat shrink, post recovery. This is Raychem SCL which as well as being a sealing heat shrink (you can see the sealant oozing out of each end) is rigid, meaning you're looking at two sealed AND strain relieved splices.

And to keep the harness as small as possible, it's best practice to do all you can to stagger spices. I have one more to go in this general area (the left signal) and so far, so good.

Crimp vs solder, good choice. Factory wiring harnesses crimp everything for that main reason, learned this when I took apart a couple Audi harnesses. Love the results here!

Is this straight from the head or mostly copy pasted. I can geek out to but im by no means that consise.