4v fast xfi with distributor. Timing showing on laptop at idle is 39 degrees at (BTDC), and crank is showing about 25 degrees with the timing light at (BTDC)??? What could cause this? I have the crank referance angle set to 50 like fast calls for, any ideas?

 

I do not know a lick about FAST, but is there a feature to force or lock the timing? Accel Gen 7 has this feature to check the timing.

 

Open tune, goto view, then sys config, then operational parameters. Lower left is the timing test feature.

 

Ok, I'll check that out, also MMR said I could adjust the crank reference angle. So I'm going to try those things.

 

Don't move the crank reference angle... just move the crank trigger until the timing matches. It should be set at 50 degrees but is not. If you are only using the distirbutor then move it.

The reference angle needs to be at least 10 degrees more than the maximum timing you are using in your table so leave it at 50 and make the ignition match.

make sure your timing is locked view>system configuration>operational parameters>fixed timing test mode if your using XFI 2.0 then check your timing.

 

This is on a 4v and the distributor is in the driverside valve cover, rotating this distributor only does rotor phasing and wont change the timing. Im am also using mmr's internal crank trigger billet wheel and using stock sensor, and the trigger wheel is not adjustable. and no matter what i do the timing wont go over 20 degrees. So im lost right now? any ideas?

 

So bottom line is the trigger wheel was not made for a 50 degree reference and the keyway was put in the wrong spot.

Your option is to move the crank reference angle until the timing matches but keep in mind, whatever you end up with.... you max timing can only be 10 degrees less than that. If you end up with 35 as a reference then the ecu will only let you run 25 degrees max. This could be a problem.

 

im awaiting a new balancer and external trigger wheel from MMR and will report back if this was the issue.

 

So the new crank trigger was installed and set crank referance to 50 degrees and started it up and chech with timing light and it was right on the money!! i tested it at low and high timing and low and higher rpm and i couldnt ask for it to be any better!!
So the issue was MMR's internal crank trigger was indexed wrong was off by 20 degrees.