LH2.4 Conversion

[lookforjoe]

11/21 - installed Volvo 20lb injectors (94-97 850 NA) 0 280 155 746 - couldn't get better than 17 mpg in mixed driving with the larger injectors, even with revised fuelling constants.

11/28 - with the lower volume injectors & fuelling constant reset to LH2.4 NA default, I have mpg of 24 in mixed driving.

Still have a warm up period low idle issue. Have to figure that out next.

EDIT: Forgot to include the completely new fuel rail I made back in Oct:

Fittings: 1) Fragola 496206BL Aluminum 45 Degree Female Coupler Swivel Adapter -6 AN and 2) BOOSTEC 5/16" male to -6AN Male Push On/Quick Connect Fuel Adapter Fitting (under CSV feed line)

 

[rjplenter]

I have to admire your persistence Hussein!

 

[lookforjoe]

Started on the Wasted Spark conversion for my EZK116:

soldered wires to the daughtercard for the 3 inputs and 2 output signals. 1: signal for cyl 1&4, 2: signal for 2&3. EZK goes to ignition signal on motherboard, HALL goes to conditioning signal on motherboard, + goes to 5v supply on chip daughter card.

card installed in EZK ECU. 3 heavier gauge wires are I/O for the OBDII port I added for data logging

Going to use a Mitsubishi power stage - J723T - if the Bosch powerstage is used, a separate tach signal relay has to be constructed.

 

[kmead]

Definitely going heavy on the electronic widgets this week. So I take it that this is still in pursuit of data logging what is actually going on with the timing and presumeably the knock sensor?

 

[lookforjoe]

Definitely going heavy on the electronic widgets this week. So I take it that this is still in pursuit of data logging what is actually going on with the timing and presumeably the knock sensor?

Actually, this is simply to go back to the solid state ignition setup, similar to what I had with the one sold by Allison - but with timing & dwell that I can map No more dist, cap & rotor. The LED I added to the cluster will provide visual indication of knock - I'm still waiting for my Dutch friend to have time to work on the data logging routines. He is very methodical & is building a test bed with EZK components to run his routines.

Bosch 0 221 503 407 2x2 coil ( 00136 Bosch Coil, off Amazon 11/30/16)

Bosch 0 227 100 203 power stage
or Mitsubishi J702 / J723T

 

[kmead]

So it continues to use the CPS as the trigger versus the Allison system which has the mechanical interlayer (auxiliary shaft) errors from lash etc.

Do you intend to add a cam position sensor to time injection events or is that overkill for a normally aspirated, non sequential system?

 

[lookforjoe]

So it continues to use the CPS as the trigger versus the Allison system which has the mechanical interlayer (auxiliary shaft) errors from lash etc.

Do you intend to add a cam position sensor to time injection events or is that overkill for a normally aspirated, non sequential system?

Yes. Thanks to EricH's SOHC thread, I purchased the Fiat block off plug for the Dist. Location. If I had thought of doing this from the start, it would have saved me a chunk of change having a custom distributor fabricated

LH2.4 wouldn't know what to do with a cam postion signal, so not much point adding one. If I could figure out a way to modify Motronic4.4 for a 4 cyl NA setup, that would use it (that system is now fully tunable using TunerPro software). I think what I have now will suffice though. I've now made it over 500miles without blowing a head gasket (!), so I think the timing mapping is acceptable, if not optimized. I might get better mpg's AND more power out of it with a newer gen EMS, but that would be a significant amount of addtional work... not that that has held me back so far

 

[kmead]

A glutton for punishment you are. Self induced of course. It's what we like about you.

 

[lookforjoe]

made the heat sink for the power stage and the standoff for the coils

install new wiring & connectors in the Mitsu connector - used wiring colors to match the Volvo setup

bridge harness mostly ready

 

[lookforjoe]

Worked on the body - side wiring modifications the past couple afternoons - had about an hour or so each day before it was too cold to stay outside (time to get a heater in the garage).

Today I installed the power stage & heatsink, figured out the coil[pack placement, and installed the harness.

Engine wouldn't start. I checked the wiring continuity. Added back the ground connection intended for the old power stage (I forgot it was combined with the ECU ground), and it tried to catch, but not right. Knowing that others had issues with the wasted spark board output connections, I reversed ignition wires 1&4 with 2&3, and it started up nicely.

Since I know it runs, I removed the distributor & installed the Fiat blanking plug. Just need to tidy up the harness positioning.

 

[lookforjoe]

The tach doesn't work with this setup - the output signal from the 6cyl power stage doesn't work with the Fiat tach. Fortunately, all this stuff has been figured out by smarter people than me - the MS crowd has a schematic for powering a 'high voltage' tach.

MS diagram in top left.

Added the modified relay wired into the circuit, and tach works as it should. Made the isolated junction block from the backside of the speedo housing of the Fiat instrument cluster

 

[Oom_Paul]

I had to do exactly the same thing with my Megasquirt earlier this week in order to get the Fiat tach to work.

Works beautifully now, although the MS allows me to tweak the frequency of the output to get a more accurate reading on the tach.

How accurate is yours?

 

[dcioccarelli]

The tach doesn't work with this setup - the output signal from the 6cyl power stage doesn't work with the Fiat tach. Fortunately, all this stuff has been figured out by smarter people than me - the MS crowd has a schematic for powering a 'high voltage' tach.

MS diagram in top left.



Added the modified relay wired into the circuit, and tach works as it should. Made the isolated junction block from the backside of the speedo housing of the Fiat instrument cluster

Right, the fiat tach is an impulse tech and requires a high voltage "spike" caused by a collapsing magnetic field. Here they are simply using the coil in the relay for this purpose. Tach adaptors for after market ignition systems like MSD use a small coil for a similar effect. A more elegant solution would probably be to simply use an inductor rather than a relay, but I suppose if it works like then then no point in messing with it.

Dom.

 

[Oom_Paul]

Right, the fiat tach is an impulse tech and requires a high voltage "spike" caused by a collapsing magnetic field. Here they are simply using the coil in the relay for this purpose. Tach adaptors for after market ignition systems like MSD use a small coil for a similar effect. A more elegant solution would probably be to simply use an inductor rather than a relay, but I suppose if it works like then then no point in messing with it.

Dom.

Exactly right. I faffed around with a few inductors I had lying around the house, but in the end the relay coil was the only one capable of generating a spike large enough to drive the tach. The bosch 12V relay I used generated a 40V spike when switched off after being powered.
I removed the contact inside the relay so that it wouldn't keep clicking constantly.

Cheers,
Justus

 

[lookforjoe]

I had to do exactly the same thing with my Megasquirt earlier this week in order to get the Fiat tach to work.
Works beautifully now, although the MS allows me to tweak the frequency of the output to get a more accurate reading on the tach.
How accurate is yours?

I haven't driven the car yet, just started & idled with a few blips of the throttle to see if the tach rises and falls as one would expect. It "appears" to respond normally, and idle rpm appears to be in the appropriate range - I did move the needle a touch when I had the cluster apart, as it did seem to be sitting slightly above the zero marker at rest. As a result, it may now be reading slightly low, as I would estimate my warm idle to be in the 900 range, the gauge looks like it shows closer to 7-800.

Now that it all works, I'll clean up all the wiring & routing to make it tidy as possible

I'll get a better sense of it when I have time to run it to normal operating temps & perhaps take it on the road. That will not happen until the roads are dry & free of the salt that is down now.

 

[lookforjoe]

A more elegant solution would probably be to simply use an inductor rather than a relay, but I suppose if it works like then then no point in messing with it.
Dom.

Doing a quick search, I couldn't find a picture of an inductor used for this purpose. What would that look like? It would be more compact? Isn't that like the old timing lights that clamp around the plug wire to read the pulse?
Sounds like Justus couldn't get that to work with the Fiat tach, though.

 

[Oom_Paul]

Doing a quick search, I couldn't find a picture of an inductor used for this purpose. What would that look like? It would be more compact? Isn't that like the old timing lights that clamp around the plug wire to read the pulse?
Sounds like Justus couldn't get that to work with the Fiat tach, though.

The right size inductor would definitely work, I just didn't have one around the house that would work, or at least not one that I could easily scrounge, so I went with the relay coil.
Here is an example of what one might look like (not necessarily the right size or value): http://za.rs-online.com/web/p/leaded-inductors/1245805/

An inductor is basically just a would coil, just like the relay coil is. It stores/holds energy in a magnetic field while dc current flows through it, and when that current flow stops the magnetic field collapses releasing the energy as a voltage spike that the Fiat Tachometer then sees as a signal.

 

[lookforjoe]

Hmmm. So the inductor would simply be placed in where the coil would normally be wired - (+) on one side, and the power stage pulse/tach feed on the other?
Seems like a zener diode & a couple of regular diodes can also be used - but the wiring into the harness would be more elaborate...

 

[dcioccarelli]

The inductor would simply replace the coil in the relay you are currently using. As Paul points out, an inductor is simply a coil. That being said, if the relay is currently working for you, then don't feel compelled to replace it. But I'd certainly recommend removing the contacts as they are redundant in this application.

In terms of the other circuit (below) I don't think that this is for the same purpose. It looks to be using the trying to achieve the opposite, namely using the negative side of the coul (that will have the inductive spike caused by the collapsing magnetic field) and then using diodes to keep it within a tolerable voltage range to (presumably) drive a non-impulse tach.

Dom.

Hmmm. So the inductor would simply be placed in where the coil would normally be wired - (+) on one side, and the power stage pulse/tach feed on the other?
Seems like a zener diode & a couple of regular diodes can also be used - but the wiring into the harness would be more elaborate...

The in

 

[lookforjoe]

The inductor would simply replace the coil in the relay you are currently using. As Paul points out, an inductor is simply a coil. That being said, if the relay is currently working for you, then don't feel compelled to replace it. But I'd certainly recommend removing the contacts as they are redundant in this application.

In terms of the other circuit (below) I don't think that this is for the same purpose. It looks to be using the trying to achieve the opposite, namely using the negative side of the coul (that will have the inductive spike caused by the collapsing magnetic field) and then using diodes to keep it within a tolerable voltage range to (presumably) drive a non-impulse tach.
Dom.

Yes, the contact was removed to prevent continous clicking.

The alternate schematic says it uses the coils (-), but since this coil pack doesn't really have that (unless the power stage outputs to the coil provide the same pulse) I didn't think it worth trying.