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-   -   Base timing 502 mpi (https://www.offshoreonly.com/forums/general-boating-discussion/316413-base-timing-502-mpi.html)

scottcleaver 08-05-2014 08:44 PM

Base timing 502 mpi
 
I have just completely rebuilt a 1999 502 MPI. It fired up perfect and runs well. The next thing to worry about is the timing. I know how to jump the A and B post to set the computer into the base timing mode. I need to make sure of where to set the timing when in the base timing mode. Everything I have read so far says 8 degrees at 1000 RPM while in the base mode. The only reason I am asking and making sure is that some GM motors were set at 0 degrees and the computer would handle the rest. Please let me know your thoughts on this process.
Thanks
Scott

Griswald 08-05-2014 08:52 PM

jump a&b, set for 8-10 deg at idle, done.

Griff 08-05-2014 10:23 PM

It should rev up to about 1000rpms when put into base timing mode. Set it to 8* then.

ealesh33 08-06-2014 08:08 AM

Yea, its 8 or 10. If your ecu is still in factory form and never had a tune done on it it should be 8. A good way to check is once you set it hook it up to a laptop with scanning software. or a scanner. Rev it up to an rpm where the timing stabalizes (about 2500), and check with a timing light to see if you show the same as what the scanner does.


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