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mrpav

RB26 Trigger setup with 36-2

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Hey guys, putting a trigger kit on my GTR and want to use a 36-2 disc. 
Is the G4 able to be setup to use that tooth pattern and can you setup quick start as well in the PC Link software. 
Thanks guys. 

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36-2 is no drama.  As for "quick start" I suspect not.  I assume this is some other brands terminology for a wasted spark start up - Link cant do that with the generic missing tooth type triggermodes - only some specific OEM triggermodes have this functionality.  

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Yeah it’s using temp batch fire for faster cranking. I think it might be a haltech only function. 
 

thanks for replying Adam I’m still getting my head around this. I haven’t ordered the crank trigger yet, is there any benefit to me getting the 12 tooth disc over the 36-2?

im just going to be either modifying the cas disc or putting an aem disc in for the cam sensor side of things to keep the stock look  

Faster startup I should say*

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With the 12 tooth option, the position of the cam tooth is quite critical as there is nothing on the crank to identify where TDC is.  Im not sure how clear this description will be but Im struggling to come up with a good explanation today:

With the 12 tooth set up, the only way the ECU knows which tooth on the crank represents TDC is by using the cam tooth as a index to tell it which tooth on the crank to start counting degrees from.  This generally works well provided you make sure that the cam tooth is set up to occur reasonably centered  between two crank teeth.  The potential problem comes if you have the cam edge too close to a crank edge - then with some cambelt stretch or valve train resonance etc the position of that cam tooth bounces around and may cross over that crank edge so the ecu then starts counting degrees from the next tooth rather than from the one it is meant too.  If you ecu has a built-in scope and the cam trigger position is adjustable then no dramas - its easy to check the cam tooth is occuring nicely between two crank teeth.  But with an older ecu with no scope or if there is no mechanical adjustment then it can be more of a headache.

In contrast, with a missing tooth crank trigger the crank now has a unique identifier on it which can be used to determine where TDC is.  The index tooth is the tooth immediately after the missing teeth so this is where the ECU starts counting degrees from.  The only thing the ECU checks with the cam sensor is whether or not a cam tooth occurred in the last revolution or not, it doesnot care where abouts that tooth occurred, it is only used so it knows whether the upcoming TDC is compression or exhaust stroke.   There are still some rules that apply such as you dont want the cam tooth to occur near the missing tooth area but still it is much more flexible (about 300° of freedom rather than about 15° in the 12tooth scenario so you can just eyeball it).

MARLF1a.png

 

 

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Adam you are a wizard Harry. 
I don’t think I’ve ever had a novel of a reply in any forum. 

Im going to just get the Ross crank trigger today with the 36-2 disc and for factory look I’m just going to cut the oem cas disc back to make a single tooth reference. 
 

All your post was missing was my trigger setup instructions for pc link and I’m laughing hahaha

Love it man Thankyou. Makes more sense now. 

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