LS1 24x & 1x cam angle sensor

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Knight rider
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LS1 24x & 1x cam angle sensor

Post by Knight rider »

Hi I'm going to be using a LS ecu 0411 to run my ford Cleveland engine - I've had holleys HP which died, so I'm trying this

Couple of questions which I haven't be able to find the answers for - hopefully here I will.

First off does anyone know what position the crank sensor points at the reluctor @tdc
Next for the cam angle sensor, I have a MSD cam sync which is a hall effect but is only trigger once in 720 degrees crank rotation, the LS has a halve moon trigger machined in the cam or on the cam gear itself - does the ecu need to see 50 50 on off or will the MSD cam sync work fine.

I ready have my front pulley hub machined to take the 24x reluctor just need to phase it correctly.

Also have a dead Holley dual sync I could modify as it has a halve moon trigger wheel I could make work if that needed

Cheers and thanks Jason
Knight rider
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Re: LS1 24x & 1x cam angle sensor

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Anyone ? Really just need a guide to what position the crank 24x reluctor points at the crank sensor @tdc - I'll be making the sensor adjustable

I've made my old dual sync dizzy into a 1x cam sync - thanks

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Re: LS1 24x & 1x cam angle sensor

Post by Knight rider »

This is the only pic I've found so far - be nice to confirm it - cheers

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barnym17
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Re: LS1 24x & 1x cam angle sensor

Post by barnym17 »

I wish I had an answer but I sure do applaud your ingenuity for doing it.
dannobee
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Re: LS1 24x & 1x cam angle sensor

Post by dannobee »

Your pic of the reluctor wheel is right. Remember that the LS crank sensor is above the starter on the passenger side, so if you think about it that way, the placement lines up.

The cam sensor wheel only needs the leading edge of the half moon to send the signal. But no matter how you line it up, if you unplug it, the ecm will figure out which stroke it's on by looking for the rpm to increase or the maf signal to jump, indicating engine start. If it doesn't see either of those, it'll assume it's on the wrong stroke and "switch" to the other stroke and the engine will start. Your only indication might be slightly extended engine cranking. The thing that'll really throw it off is if the cam sensor timing is off. In that case it'll try to start but it knows that the signal is off and throw a P0341 cam/crank correlation code. (Assuming a factory type pcm calibration)
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Re: LS1 24x & 1x cam angle sensor

Post by Knight rider »

barnym17 wrote: Sat Oct 09, 2021 5:51 am I wish I had an answer but I sure do applaud your ingenuity for doing it.
Thanks - all pretty easy so far
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Re: LS1 24x & 1x cam angle sensor

Post by Knight rider »

dannobee wrote: Sat Oct 09, 2021 6:58 am Your pic of the reluctor wheel is right. Remember that the LS crank sensor is above the starter on the passenger side, so if you think about it that way, the placement lines up.

The cam sensor wheel only needs the leading edge of the half moon to send the signal. But no matter how you line it up, if you unplug it, the ecm will figure out which stroke it's on by looking for the rpm to increase or the maf signal to jump, indicating engine start. If it doesn't see either of those, it'll assume it's on the wrong stroke and "switch" to the other stroke and the engine will start. Your only indication might be slightly extended engine cranking. The thing that'll really throw it off is if the cam sensor timing is off. In that case it'll try to start but it knows that the signal is off and throw a P0341 cam/crank correlation code. (Assuming a factory type pcm calibration)
Thanks, any info is a help, was trying to get hold of a engine to confirm all this but harder than you'd think.

I'm assuming that pics is looking at the front of the reluctor ?

Also thinking now I may need to balance that 24x reluctor or at least drill holes in the opposite side as it looks balanced to suit a LS
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Re: LS1 24x & 1x cam angle sensor

Post by Knight rider »

So trying to sort out the crank position sensor, mounting the sensor I'd like to face the plug connector either up or down but I'm unsure if that will make the sensor not read as I believe it's a dual track or input sensor. On the LS1 the sensor plug faces forward which doesn't really work for me as it's pointing at the alt belt

I've seen a sensor for 7.4lt that's meant to use 24x was also wondering if that would work as it would be a better fit - cheers hope someone can help


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Re: LS1 24x & 1x cam angle sensor

Post by Knight rider »

So it's running, was alot of mucking around, the drama was that as thought the crank sensor plug has to face forward as it is in a LS - only had spark on one cylinder with the sensor plug facing to the rear
Also had to change the cam reluctor to trailing edge not leading - which is strange because looking at a front mounted cam sensor on a LS the halve moon reluctor is at the leading edge

Anyway it's running , now to finishing hooking everything up and dial it in enough for a tune

Do have a question

First is the timing when it first starts it's @ 20btdc which is where I want it but drops back to zero after a couple of seconds - idle is high so wondering if the ecu lowers timing to try and control idle speed ?

Also is there a crank sensor like the one for a 454 vortec that I posted before that will work with the ecu 24x reluctor as that one would be easier to mount for me - cheers

https://youtu.be/eEKcm_Sexbw
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