55superbeetle

iTrader: (5)

Can someone explain how the 24 tooth dual trigger wheel works? Im doing a megasquirt install on my lq4. My plan was to remove a tooth of the stock 24 tooth wheel, allowing me to not have to worry about the cam sensor as I would have a TDC sync now. I know I need to trigger off the falling edge because its the side that is evenly spaced but the dual wheel thing is throwing me for a loop. Can somebody shed some light on this? Does the hall sensor only pick up on one of the wheels?

Thanks
Jeff

CalEditor

iTrader: (1)

I am under the impression that the 24X LS engines have 2 "trigger wheels" that are assembled together, but offset. The single crank sensor is a logic sensor 2 in to 1 out. This sensor produces 1 signal out.





This is a bad pic. I have a better one someplace

55superbeetle

iTrader: (5)

So the hall sensor is reading both the trigger wheels and combining them into one output? Now I just need to figure out how to remove teeth to get a clean missing tooth pattern. Any ideas? Since they are kinda like offset mirror images of each other I guess I would just remove a tooth and its next one on the second trigger wheel. I guess if I cant get it to work I can always just put a trigger wheel on the front. Just didnt want to deal with pinning the pulley.

rpturbo

iTrader: (47)

I think pinning your pulley will be easier, but to each their own. Let us know how it goes. I have always thought the Megasquirt was cool, but never messed with one.

Gabbiani

iTrader: (20)

I've done it both ways on an ls1. The wheel on the pulley was easier to get running. If you remove a tooth you need a degree wheel or way to figure out where the #1 tooth is.

You have a 24x wheel and a 1x wheel with an ls1. The cam spins half the speed of the crank so one cam revolution the sensor reads high, the next low. The computer knows tdc occurs when it detects a change on each sensor. So the cam switches from high to low and the crank hits a tooth at the same time. My experience has been the MS is very sensitive to noise runing this setup. I haven't tried removing a tooth from the 24 but that might be easier if the engine is apart.

jergren

iTrader: (1)

Stop trying to make the install harder than it is

You need to be running MS2Extra (one of the beta versions) 303Y 20101208.
You do not need to use the cam sensor!
You will not need to modify the crank wheel.

Read, read, read!
http://www.msextra.com/forums/viewto...?f=101&t=30043

I'm running a LQ4 on MS2 V3.0 with MS2Extra 303Y.

55superbeetle

iTrader: (5)

WOW, Thanks for posting that. That solves all my problems!