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another MSD launch master nytro ?

mattymac

Extreme
Joined
Jun 13, 2006
Messages
51
I have searched and havent found the answer to my problem.

I had a msd LM on my apex. put a motec on that so I figured id put it on my nytro. All the threads with running it on a nytro say to leave the one pair of plugs open and unhooked.

When I did that and turned the key on I got the power on/red LED to light up on the LM, started the engine and it sounded horrible like the ignition timing was way off or it was running on two cylinders? Also when the engine fired up the red LED on the LM stayed on. On my apex it would come on then turn off when the engine started, only to light up again when I would push my button to activate the LM.

I thought maybe the wiring was in reverse order (not even sure if that makes a difference from 123 to 432/321) flipped the harness on the LM and it did the exact same thing as before?

Also thought maybe I didnt get one of the coil plugs seated so one cylinder wasnt firing... All good, everything connected, seated etc.

I unhooked it from the sled and it ran perfect as before?

I know people have ran the LM with no problems on the nytro??? Is there anyone here who has or known of this happening on the three cylinder?

The LM worked perfect for years on my apex, when I pulled it and swapped it everthing worked perfect, now its giving my nytro fits.

Any help is greatly appreciated!
 

got it figured out,

Per the MSD instructions it states when the key is switched on the red LED will light up signaling that the coil harness has power on the 12v side of the two wires. The box did exactly that. Then when the engine starts the light should go off. Mine stayed on.

I ended up switching the 4 wire plugs at the box flipping the 12v+ and signal wires. Apparently the apex and nytro are opposite ignition coil wiring.

As soon as I flipped the plugs it did everything it is supposed to. I was thrown off because I knew it worked the way it was configured on my apex so my mind was already thinking that it should work.

Now only being 3 cylinders the rpm count is different so the rotary switches for RPM is different. The box setting is around 1000 rpm lower than actual engine rpm cutout.

I have it wired into my brake switch and it can build about 2 PSI at 3700 RPM.
 
You got that worked out with the LM 4350?
Yeah works just like it supposed to on my nytro.

I could make a bit more boost with it on my apex, 6-7psi

It only makes about 2 psi on the nytro.

Most people activate their LM and go WOT, if you go about 1/4 throttle then slowly ramp up to 100% throttle I could get my apex to light up and really start popping and sucking through the intake to where it would make the 6-7 psi at around 4000 rpm. Then when you let go of the button it was instant track speed.

I cant get the three cylinder to catch at that same 1/4 throttle and take off like the apex did but it still is a huge improvement over not having one.
 
Awesome. I'm going to get on on the way for the Viper. Any amount is better than trying to leave on the brake!
 
got it figured out,

Per the MSD instructions it states when the key is switched on the red LED will light up signaling that the coil harness has power on the 12v side of the two wires. The box did exactly that. Then when the engine starts the light should go off. Mine stayed on.

I ended up switching the 4 wire plugs at the box flipping the 12v+ and signal wires. Apparently the apex and nytro are opposite ignition coil wiring.

As soon as I flipped the plugs it did everything it is supposed to. I was thrown off because I knew it worked the way it was configured on my apex so my mind was already thinking that it should work.

Now only being 3 cylinders the rpm count is different so the rotary switches for RPM is different. The box setting is around 1000 rpm lower than actual engine rpm cutout.

I have it wired into my brake switch and it can build about 2 PSI at 3700 RPM.
Got a pic of the wires you switched?
 
Got a pic of the wires you switched?


I just switched/reversed the 2 plugs that come out of the box that plug into the coil harness. One is for 12v (red wire plug) and the other is the coil signal wires. Just switch the plugs.
 


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