MegaSquirt install writeup

[gmail]

I use stock crank wheel.. also use the stock cam sensor so I have fully sequential for fuel and spark.

The stock crank is 3 tooth and the cam is half moon so it can detect where #1 is

 

[gmail]

If you use the dis and dont want fully sequential you only need crank sensor as it only needs 1 wire for spout. It basicly will run it as if it were a distributor .. the coding for the dis is tfi ignition

 

[Falconvan]

Is the crank trigger on the front or on the flywheel like the FI Mopars? I was wondering what flywheel ill need with the manual trans swap.

 

[Off Road SHO]

Falcon,

The SHO's crank sensor is on the front snout. Just as an FYI for your project, You can use any transmission that bolts up the 5.0 5.8 block if you use one of the CIDIDIT adaptors. That opens up a wealth of clutch and flywheel opportunities to you.

Tom

 

[Falconvan]

I've been looking at that but I think initially I'm going to go with a Ranger 3.0 trans as long as the shifter comes out in the right spot.

 

[gmail]

People claim the ranger trans dont like high revs like the SHO does so it wilp **** it off prematurely.. I do know the ranger trans that cines on the 3.0 vulcan bolts up but you can use all the insides of a 4.0 trans to go inside the 3.0 case to make it handle as I understand 400 ft lbs of torque...

Mind you I read all the last part and I dont know threw experience just what I read

 

[Falconvan]

That's good to know as both of those transmissions are reasonably priced for used ones.

 

[hawkeye18]

This is a fantastic write-up! I just have one thing to say about the wires.

You said that you used single-core wires because the multi-core wires are too hard to solder.

I say, whatever works is well and fine, but there is a reason multi-core wire is exclusively used in automotive and aeronautical applications: single-core wires are extremely prone to internal breakage from vibration or repeated movement.

Proper application of multi-core wiring involves tinning the wire before you solder it. When you tin the tip of the wire, it behaves like a single-core wiring for soldering purposes while retaining the flexibility of multi-core wiring.

I cannot in good conscience recommend using what is essentially house wiring in a car. It will work just fine at first but I think you will find that in a few years you will have a lot of strange electrical issues!

 

[gmail]

This is a fantastic write-up! I just have one thing to say about the wires.

You said that you used single-core wires because the multi-core wires are too hard to solder.

I say, whatever works is well and fine, but there is a reason multi-core wire is exclusively used in automotive and aeronautical applications: single-core wires are extremely prone to internal breakage from vibration or repeated movement.

Proper application of multi-core wiring involves tinning the wire before you solder it. When you tin the tip of the wire, it behaves like a single-core wiring for soldering purposes while retaining the flexibility of multi-core wiring.

I cannot in good conscience recommend using what is essentially house wiring in a car. It will work just fine at first but I think you will find that in a few years you will have a lot of strange electrical issues!

I couldnt agree more about single core wires.. only thing is tho my setup is stationary so I dont expect it to move much... also since this writeup I moved the megasquirt to under my center console which ment I had to extend the wires and I had multi core wires only so I rewired the setup.

Reason I like single core wires is because they also are stiff and you can use thinner wire compared to multicore.
Either way your right I shouldn't recommend using it to others as it could cause potential issues

 

[SHOtime2511]

Great to see someone going this route. I may do the same.

 

[gmail]

I agree.. I love the ability the megasquirt has.. I am waiting till monday for some more stuff to come in the mail and im gonna be hooking up my speedo and a wide range knock sensor .. once I get my speedo setup I will be able to do a bunch more things like be able to limit power like for boosted setups 3rd gear lol or make the power more progressive so I dont spin all threw 1st and 2nd and as you shift the power increases.
With the knock setup im going to be able to more fine tune my timing so there is no knock. Not even a little and I can set filters on it.. valve noise and other things make noise the knock sensor can pick up and other times the knock sensor dont see knock in factory setups above x rpm or below etc

 

[vetteboy]

I'm doing a similar setup in my project, except with the Holley HP EFI system. Same basic idea though. I got it with the unterminated main harness so I'll be building a stripped-down harness with just what's needed.

Do you happen to know if the stock crank sensor/trigger wheel is rising or falling edge, and how many degrees it falls before TDC?

edit: had to take the front cover off mine for something else, looks like TDC is about 70 degrees after the falling edge and 10 degrees past the rising edge. Does that sound right?

 

[Aspect]

I have been thinking of using a Megasquirt on my 87 LX. Keep up the good work and let us know what results you get when completed.

 

[gmail]

I remember for sure it's falling edge but I will have to check my laptop when I'm near it again for the degrees it at.

I really need to go through this and re write it all as this is too sloppy and not explained how it should be.

As for a update the car runs like a champ on megasquirt. Need to get it to the Dyno and tune the spark for top power. I am curious to see how close my timing is. Feels pretty close but Dyno tells all.

I have it running fully sequential and currently have the Chrysler coil on plugs on the car even tho I got a set of lsx truck coils kinda went back and forth until I figure out how I want to mount the ls coils.
In case you are wondering the ls truck coils are as far as I know the strongest spark you will get for any coil on plug.

I recently installed 6 egt probes . One per cylinder and was playing with tuning each cylinder individually. Also got a idea how well the intake setup with snakes flows.

It's not like you would think with the back 2 cylinders not getting enough air. Actually does seem to get a pretty darn close to even flow through the intake.

If I recall the only weird issue with the stock intake is the second the butterflies open the transition period seems to have a flow imbalance and I want to when I have more time play with a completely stock intake with horns to see how they work Compared to my intake that's ported to the moon and bbbs with bigger throttle body.

My guess is the horns work to scavenge the air out of the plenums. Example being look at where the shorts and longs meet inside the surge tanks. The inlet port is flush so when the longs are pulling air and the shorts switch over the air flow is redirected to the shorts which has a second to starting changing direction and velocity.
I think with the horns it pulls it from a different spot and has a better chance of the air moving in a more desirable manner.
Basic idea I'm getting at it a set of shorty fatter horns would help a modified intake flow better.

This is just a thought for now and need to play with it more to get the answers.

But anyways that aside the car runs well and I need to spend more time setting up more features like launch and flat shifting etc. I do have a video when i had the tune off a little but I disconnected the maf and dis module to show I'm running solely off megasquirt