They are heat range 8.

If this is the way theyre supposed to run, id like to find someone who can better tune these MEFI3 ECMs.

Id rather have it run clean and maybe add a wideband to monitor with less fuel.

I also noticed that both motors are set at 12 degree base timing, where the Whipple manual says 8.

8* of timing is correct, adding O2 sensor's is a good idea.........I went from #8's to heat range 7 and it seemed to help, where are you located ?

Seattle area.

would you recommend scaling back to 8 degrees?

I’m Noting , not telling…..8* recommended in Whipple’s 500EFI Install directions
https://whipplesuperchargers.com/ind...tachment_id=41

Base timing needs to be set @ 8* and let the computer do the rest, what are you using to look at codes and timing ?

Snap on timing light

I do also have the Techmate tool.

I will re time them to 8 degrees.

do I need to do anything in the computer to tell it that I’ve reset timing? I see there’s a base timing mode, not sure how that works?

thank you for all your help!

Yes, you need to put it into base timing mode......you will hear the engine rev up a bit, set to 8* then remove it from base timing mode

wouldn’t you theoretically want to go to a heat range hotter if plugs are already fouling? Going down a heat range, on paper, would be worse?

In the NGK world lower the # the hotter the plug