Page 1 of 1

trigger setup of comaro engine

PostPosted: Sat Jan 09, 2021 11:27 am
by EagleEyeMotors
Im working with project Comaro SS (LS3) engine 2012 thats swap and installed with Nissan and tuned by M84 ECU the engine is running but I need to be sure that the trigger setup is correct
ref/sync mode 17
crank ref teeth 60
tooth ratio 50
crank index position (CRIP) 67
ref sensor type 1
sync sensor type 1
sync trigger voltage 0.5

Im not sure about the crank index position because LS engine dose not have timing mark but the engine run without problem but I'm scared from (CRIP) angle

Re: trigger setup of comaro engine

PostPosted: Sat Jan 09, 2021 12:14 pm
by David Ferguson
Dead-Stop the engine on Cylinder 1, and go through the steps to make a timing mark. I did that with an LS3 Engine running on an M1 with custom firmware and discovered the CRIP was 10 degrees off from what the package was using.

Here is a description of the process:

https://www.hotrod.com/articles/accurat ... iston-tdc/

I made a tool from an old sparkplug that allowed me to screw a long bolt into the cylinder head as my stop for the piston.

Re: trigger setup of comaro engine

PostPosted: Sun Jan 10, 2021 10:58 pm
by Sean
viewtopic.php?f=11&t=4684#p21283

Stephen Dean here says starting crip is 80. I have an LS7 file at 78 degrees crip. As David said, you must go through the process , it's only guessing otherwise.

David Ferguson wrote:Dead-Stop the engine on Cylinder 1, and go through the steps to make a timing mark. I did that with an LS3 Engine running on an M1 with custom firmware and discovered the CRIP was 10 degrees off from what the package was using.

Here is a description of the process:

https://www.hotrod.com/articles/accurat ... iston-tdc/

I made a tool from an old sparkplug that allowed me to screw a long bolt into the cylinder head as my stop for the piston.

Re: trigger setup of comaro engine

PostPosted: Mon Jan 18, 2021 9:21 am
by stevieturbo
You could fit a pressure transducer into cyl 1, hook the spark trigger up to the scope as well and crank it over with timing set to 0deg.

You'd get a visual reference if it is correct.

Re: trigger setup of comaro engine

PostPosted: Mon Jan 18, 2021 9:23 am
by David Ferguson
I've done that for bike engines with no exposed crankshaft. It works.