Big Bore Map to Stock Bore Map

[Mtneer Man]

Ok ive got a map for a  727 with a single and all other mods are the same. How much should i lean it out to get close

[SandDragon]

Bore size should not effect the map... compression will, but I believe if you did a 9.2:1 727 it would use the same map as a 686.

[Mtneer Man]

Sorry, i should have been more specific on what i was asking. I did get it figured out though

[Colorado700R]

Bore size should not effect the map... compression will, but I believe if you did a 9.2:1 727 it would use the same map as a 686.

SD, I'm confused.   A larger bore will require a larger total volume of fuel/air mixture to run correctly.  The larger piston will be drawing a larger volume of air into the cylinder and so the FI map will need adjustment to meet the ~12.7 to 1 A/F ratio.  I would think a SB map would be very lean?? 

And I also thought that compression should do very little to map requirements, since the A/F requirements would not increase or decrease?

Aaron

[pdxmatt]

That is correct. If you displace more air, you need more fuel. And compression should not affect your map.

[SandDragon]

You are correct Clorado... I smoked alot of weed in my day.  LOL  I guess my brain was slow when I posted that.  OOPS!    I will say the 12.7 should be 13.1.... 

[Colorado700R]

You are correct Clorado... I smoked alot of weed in my day.  LOL  I guess my brain was slow when I posted that.  OOPS!    I will say the 12.7 should be 13.1.... 

When you say "Back in the day", you mean two weeks ago ??   


Aaron

[SandDragon]

I mean October 18th 2005.    Well at least that is the last time "remember" drinking or getting high.  :grin_nod:

[ThisGuyAlex]

you sure about that? that front bumper looks like something out of a scary acid trip.....