On "Microsquirting" the Porsche 914

Ignition Coil, Bracket, and Injectors

Back to Part 4

Remember the IGN4-VW coil? Install was going to be a breeze...or so I thought. I tossed around several location ideas and wasn't happy with them. Then EricP showed me a bracket he made to install his in the area where the original distributor was...of course! Duh. Eric fabbed a bracket that also mounted his MPS, but since I didn't need that I "went simple" and made a plate out of sheet metal I had laying around. It fit right over the distributor hole plug and used the distributor clamp stud and two sheet metal screw holes. Drill, tap, three rivnuts later and the coil was mounted.

3/28/22 Update: Please read Part 11 Addemdums. I no longer recommend mounting the coil here, as it was overheating and causing misfires. Description and photos left for reference -- of what NOT to do... ;)

By the way, this wasn't the first time Eric saved my bacon...the TPS choice and TPS mounting bracket was his idea too...

The credit card had rolled over and I ordered the FiveO Motorsport injectors. As suspected, they bolted right into the original D-Jet locations and even came with new seals.

FiveO injectors on left, original D-Jet on right

The FiveO injectors come with straight hoses versus the D-Jet's curved hoses. The 914 needs curved hoses to clear the engine compartment frame rails. These are available from any 914 supplier, such as Pelican Parts.

Note the photos here describe the mock-up, using the the straight hoses that came with the injectors. Trust me, you want the curved ones.

FiveO Injectors installed in D-Jet location

Here's the engine with a few more parts installed! Prosit!

On to Part 6: "Ignition, Wiring, and Terminals, Oh My!"

TDC - Top Dead Center, the firing position for #1 cylinder
CPS - Crank Position Sensor, also known as CAS, Crank Angle Sensor
TPS - Throttle Position Sensor
MPS - Manifold Pressure Sensor
IAT - Intake air Temperature sensor
CLT - Coolant temp sensor
AFR - Air-Fuel Ratio
FLAPS - Friendly Local Auto Parts Store

Comments

An Interesting GTSB (Greg Transportation Safety Board) Report

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On "Accusumps"

(This is another blog in a series of thoughts/ideas that I commonly see, created as a placeholder for future reference so I don't have to re-write it each time. I totally understand the limited audience and for such a post, but I invite feedback from those who have interest in this arcane subject...) -------------------------------------------------- This was posted in response to someone inquiring about PDM control, pressure sensors, switches, valves to manage an Accusump in his race car... You're making this wicked too complicated...and significantly failure-prone. An Accusump (AS) is a passive hydraulic/mechanical oil pressure accumulator (thus, "Accu"sump). Its purpose* is to provide oil flow when the pickup tube in your engine becomes unported due to side loads oil "slosh" or flow away from it. First, note that an AS is a "BandAid" for a design flaw in your road race engine. That design flaw is the unporting of the oil pickup. The ultimate res...

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