Megasquirt System on Supercharged Type 4, 2.0L with twin plug heads Options

[poorsche914]

EDIT Swapped out the engine with my 2056 so I could drive this car. I plan on installing a MegaSquirt system on the supercharged engine.

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After failing to get the supercharged T4 engine running properly with the progressive Weber originally installed, I am ready to go the Megasquirt route. In talks with the owner who had this 914 in the early/mid '90s, it has been determined that this setup has never run well. He had a euro auto shop tune it and they got it to run somewhat decent but never reliable. I am hoping a modern FI system will bring this unique build to life!

Below is my MS parts list:

MS Wiring Harness #
Crank Trigger Pkg #
Modified Coolant Temp Sensor #
Relay Board & Cable #
Mini Cam Sync #
MS2 v3.57 *
EV1 Fuel Injectors *
TPS *
IAT *
(8) LS2 Coil Packs w/Brackets ** ebay/amazon
Bosch Lambda Sensor (1 or maybe 4***) ebay/amazon

# from thedubshop.net
* already have from used fuel-only MS system I bought
** I need eight coil packs since I plan to use the twin plug setup
*** I am thinking of going with (4) of the Lambda sensors (one at the end of each tube of the heat exchangers) so that each cylinder can be individually tuned. Is that something MS supports? Is it even necessary? From what I've read, for a stock setup it is not needed but I am thinking with the supercharger it may be useful. (IMG:style_emoticons/default/confused24.gif)

Current SC setup is, from top to bottom: Carb > SC > Plenum > Runners > Heads
The intake runners are modified runners from the single Weber kit - slight bends to fit from heads to center-mounted plenum box.
My idea is to have stock runners similarly modified so that the new setup would be: TB (mounted on custom plate similar to how carb is currently mounted) > SC> Plenum > Runners > Injectors > Heads

I am hoping a tunable fuel injection system is what this engine needs. And, if not successful, I will remove the SC and run the engine as a twin plug.

Anything I am missing? Anything I don't really need?
I am ready to gather together all the parts I need and start putting it together first of the year.
Would like to have it running and tuned to take to Werks Reunion in March (IMG:style_emoticons/default/rolleyes.gif)
EDIT: This particular project postponed til I have more time.

Thanks!
steve
(IMG:style_emoticons/default/driving.gif)

[JamesM]

Anything I am missing? Anything I don't really need?

You are going to need a MAP sensor or 2 (I recommend 2 so you have baro correction)

I would ditch the MS2 v3.57 and the relay board and run Microsquirt utilizing the stock relays instead, will be an easier/cleaner install as the Microsquirt is both smaller and spec'd to live in the engine bay. The relays you need already exist on the stock relay board, just use the same connection that d-jet does. The full blown MS2 is overkill and wont gain you anything anyways.

Ditch the cam sync completely. Added complexity for zero gain

Ditch the 8 LS2 coil packs and run dual VW 4 post logic level coil packs, bank fired.

If you are going back to stock d-jet intake runners I would run injectors that fit them without modification (but that is all up to how much fab work you want to do)
These are high impedance and fit the stock runners and fuel rails:
https://www.fiveomotorsport.com/a280-a380-h...-fuel-injector/

I wouldn't worry about the 4 wideband sensors and individual cylinder fuel trim, the rest of the motor isn't that precise and you are already getting HUGE gains in fueling precision going from a carb to Megasquirt.

I dont see any reason why the motor wouldn't be reliable when properly setup. Im sure proper fuel and spark control alone will add a decent amount of power and reliability to that motor.

https://www.youtube.com/watch?v=nljeNyH07Cs

[poorsche914]

Thank you, James, for your expert advice.

I will add MAP sensors to my list.

I originally bought a Microsquirt ECU about a year or so ago with plans to convert my 2056 from carbs. Ended up selling it to a local friend last fall to help him get his 914 ready for an event.
The used system I have includes the MS2 v3.57 and thought I would need it to run twin plugs. Does the Microsquirt support twin plugs?

Cam sync and LS2 coil packs and 4 wideband sensors... I was thinking more control might be of benefit esp. with supercharger but if it just adds complexity... (IMG:style_emoticons/default/ar15.gif)

Here is what I currently have:

MS2 v3.57 ECU
Wiring Harness: main and a smaller one (see photos)
Filter housing, TB, plenum and intakes from 2.0
Aftermarket high impedance fuel injectors
Plus various other stock D-jet bits and pieces.

I dont see any reason why the motor wouldn't be reliable when properly setup. Im sure proper fuel and spark control alone will add a decent amount of power and reliability to that motor.

This is what I hope for. It should be a fun engine with plenty of power.

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[JamesM]

The used system I have includes the MS2 v3.57 and thought I would need it to run twin plugs. Does the Microsquirt support twin plugs?

It can, depending on how you plan on firing the plugs. Microsquirt has 2 logic level ignition outputs which if you fire in wasted spark mode should be all you need for this. Basically, with two 4 cylinder coil packs we are just doing a dual wasted spark setup. Wire the first coil up exactly as you would a normal wasted spark setup to the primary plugs. Then, because we are working with logic level outputs, you wire the 2nd coil pack up the exact same way, using the same ignition outputs with the leads connected to the secondary plugs. End result is the firing of 4 plugs on each ignition event, 2 on the compression cylinder and 2 on the wasted spark cylinder.

Cam sync and LS2 coil packs and 4 wideband sensors... I was thinking more control might be of benefit esp. with supercharger but if it just adds complexity... (IMG:style_emoticons/default/ar15.gif)

Exponential complexity addition for what would be an imperceptible if not completely non existent difference.

I would consider starting from scratch with the harness, probably save you some time and headaches.

[poorsche914]

I would consider starting from scratch with the harness, probably save you some time and headaches.

The harness looks to have been done quite well with good connectors and shrink wrap so plan on using it. I will test all the wires just to be sure there are none with issues.
I believe this is the unit @ndfrigi had in one of his 914s. Maybe he will chime in with any caveats.

I plan on crank trigger at some point but have read to start with fuel only to get a feel for the MS system.
Since coils are "noisy" and interfere with MS, what are thoughts on sending signal to the tach via CDI unit? I have a vintage blue Permatune that I could use.
I also have the Crane Cams XR700 that came with the rest of the MS stuff that I could use with supplied distributor but prefer to keep my Mallory distributor with Unilite module since I know it works.

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