Highlander

Would you trust your timing to a 4x signal crank sensor???? i mean... basically no cam signal and a 4x crank?? gm used 24x on ls1 and 58x on ls2... go figure... Fast uses 60x iirc.

You can also use the LS1 PCM with a vortec truck bin. Since it used the same ls1 pcm with a 4x crank signal. Worst case scenario is changing the front cover. But...

I wonder if you could machine a reluctor ring so small to fit under that cover on the crank that uses 24x or something similar and then use an ls1 pcm.

Alvin@pcmforless.com

The LS1 PCM is awesome for boost. In fact theres not a whole lot it can't do now with the different OS patches that are out.

I wouldn't hesitate at all runing a megasquirt with a 4x crank signal. It has been done for years on other platforms.

Highlander

I wonder if the ls1 OS can run from a 4x signal also (not using the express van OS)

engineermike

I did some reading on ls1tech and realized that Parish8 (twin turbo LSx 4x4 chevy truck making 1055 rwhp) is using a MegaSquirt. His is wired up just like I proposed, letting the stock ECM do IAC, spark, security, HVAC, gauges, etc. He also speaks of a 9 wire installation.

Mike

jakesz28

I'm looking at the megasquirt now.
So I'll give this a bump.

Eric Bazan

Is this real time tuning still a possibility?

Eric Bazan

1fastgixxer

i plan on putting a msII on my lt1 this winter. gotta go with the edis 32-1 to make it work. it is totally worth getting rid of the junk opti .

jsetzer

I will have a full write up soon. As far as I know I have the only boosted, msII controlled lt1 with fuel AND spark controlled by the MS with NO OPTI. I have the metal plate from the opti attached to the timing cover because I couldn't find a 3" freeze pluge. No sensor, no cap, no rotor.

I am running edis8 with 36-1 tooth wheel. Setup was a breeze, tuning has been super easy so far.

Things I did not anticipate but have been an issue.
-Injectors take @ 1.0ms to open/close. I have 60# injectors and was running 4 squirts per event (720 degrees) my idle was super rich and with autotune on (using the wideband) it would try to pull my VE down so low that the injectors did not have time to open, so I was at idle with on/off fuel control. Backing this down to 2 squirts takes care of the problem, but you should run the smallest injectors possible for you power goals.
-coolant sensor - you can use your stock on, but you either give up your gauge or your signal to the stock pcm, which would mess up your fans and possible spark tables etc if using the stock pcm for spark. I know have a sensor in each head and one in the pum. Gauge/pcm/ms
-no resistor needed for thermosisters - using stock sensors and everything calibrates fine
-did the kit - took @ 10 hours to build it - only found one bad joint when I tried to run it the first time - wiring the car has probably taken longer. Yes its not many connections but to do it clean has taken a lot of time - edis8 has a lot of wiring too, needs to be shielded, etc. I have a good 2 weeks worth of wiring a couple hours a day now
-nobody makes a spark plug wire with an edis8 coil pack connector on one end and a 90^ gm boot on the other. I used my taylor wires and cut/recrimped the coilpack connectors onto them.
-edis8 is extremely forgiving - I plan to clean up my brackets but my reluctor ring is not perfectly centered and my pickup has a bit of an odd angle to it - works fine though
-98% of the tuning can be done real time -after the initial setup and calibrations all of it can be done real time.

1fastgixxer

how and where did you attach the edis wheel? pictures would be great.

are you running off the MAP, or TPS, or both?


btw summit has a freeze plug that will block the opti. i dont know the part number, but i know they have one.

jsetzer

Speed density uses map, tps, and rpm to figure required fuel, as well as corrections from IAT and coolant temp. The only place you really have to decide between the map and tps is for accel enrich, like quick openings of the throttle. In this case you have a slider, you can do all tps, all map, or anywhere inbetween. My default was tps only and while it did the job it seems much smoother with a mix of both.

I'll have to get pics later for my write up, but the wheel is just a stock ford wheel and we made a bracket to attatch it to the harmonic dampener. I need to get it balanced now but it sticks out @ 2 inches from the face of the pulley. Another friend made a bracket to hold the pickup, it bolts to two unused holes in the block and then has an arm that sticks out to where it needs to be.

Its only been driven a few miles so far but I hope to take it to a car meeting this weekend and beat on it some.

jakelund

Since all (?) aftermarket plug´n play ECU´s for LT1, triggers ONLY of the low-res signal from the opti I must wonder, haven´t anybody made this work? It seems so easy..?

Either the falling or rising 8 edges of the opti-wheel slots are aligned with each other, so how hard can it be? And its a 12V or 5V HALL-signal that just about any ECU could trigger from.

Looking at plug´n play FAST XFI schematics for LT1, the only trigger connection is of the low-res signal wich gives a 4x crank hall-signal. (actually a 8x cam signal, of course)

And in lack of cam position sensor the XFI fires the injectors in a “semi- sequential” order, wich seems to work fine, but still, not true sequential.

I may have to try this myself, but I´m not sure my opti-signal is good since I have misses in the upper RPM´s.. but if so I´m thinking of putting 4 trigger tooths on the damper and use a Honeywell GT101 hall-sensor and just use the opti as a distributor.

Can´t see how it would be easier or better with EDIS-system..

If I weren´t so lazy I would put a 1x hall-sensor in the opti and go COP and fully sequential. (Megasquirt don´t do sequential, though, atleast not yet, that I know)

jakesz28

I don't think the edis8 will let a motor rev to 8000rpm. I want to replace the stock ecm because the tables stop at 7200. I'm going to be running a single plane with a solid roller so I need a ignition that will go 8000 without missing a beat.

I was looking at the edis8 but have changed my mind.

jsetzer

Everyone's setup is different. I will not be revving to the moon. If you use the pickup low rez from the opti and then the cap and rotor... whats the point? Just keep the stock ignition and figure out your fuel... hell run a boost referenced FPR.

I have read that people have used the low rez pulse, I have not tried it. I have no opti, I am using coil packs, and it was cheap. My entire edis8 setup was below $100 - Find me ANY solution that can say that.

Yes MS has been run with full sequential, but its not officially supported yet. Again, if it was a simple on/off switch I would run sequential, but with the tau-x adjustments and the ton of tuning options, why do I care?

For you naysayers, the answer is cost. Price me an xfi system, hell find the same setup as mine (unlikely) and compare peak power, curves, economy, etc and see if it was worth it. $250 for MS, $100 for my edis, and I am completely stand alone.

jakesz28

I have nothing against or what you are doing. I'm trying to find a cost affective option myself. I'm just letting other people know that the edis8 is nice but if a person is looking at aftermarket ecm's there most be a reason why. So if someone else has the say problem I am faceing I hope that I'm giving them usable info.

I have not purchased the MS yet but plan to shortly if it looks like it will do what I want.

As far as my car the opti may very well be going. I have a single plane intake and can very easily run a distributer.

I wouldn't mind asking you some questions if you don't mind.

jsetzer

My old plan was a big solid roller with a standard sbc intake tapped into the intake and a crank trigger to drive it. MSD triggers can get pricey.

My goal was to get rid of the opti all together. I had my fair share of issues with them, but it honestly did all I needed. Most of my projects are to see if I can do it, not that I really need to lol.