Changed engine, adding fuel to tune?
Changed engine, adding fuel to tune? Getting my new engine installed finally, and thinking about the differences between old and new. Think about adding say 5% globally to the fuel table. And taking a hair out of the timing mid to top.
This won’t be a final thing obviously, just a temporary safety measure for first start and break in before heading to the tuner.
old engine: iron 6.0, flat tops, ported 243’s, approx 11:1 to 11.25 comp, fast 102/102, 233/238 111+2 cam, 1.875 tsp headers, tsp 3/3/3 y-pipe, 3” magnaflow muff.
new engine: aluminum 6.2, piston squirters, 11.8 comp, tfs 235 heads, 230/234 114+2 cam, fast 102/102, 1.875 headers, 3/3/4 ypipe, 4” free flow exhaust.
id appreciate any experienced advice
This won’t be a final thing obviously, just a temporary safety measure for first start and break in before heading to the tuner.
old engine: iron 6.0, flat tops, ported 243’s, approx 11:1 to 11.25 comp, fast 102/102, 233/238 111+2 cam, 1.875 tsp headers, tsp 3/3/3 y-pipe, 3” magnaflow muff.
new engine: aluminum 6.2, piston squirters, 11.8 comp, tfs 235 heads, 230/234 114+2 cam, fast 102/102, 1.875 headers, 3/3/4 ypipe, 4” free flow exhaust.
id appreciate any experienced advice
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
You are switching from a cam with 14 degrees overlap to a milder one with 4 degrees of overlap.
As such I would add 10% fueling to everything below 1400 RPM and and less % at each RPM step above that until adding nothing at 2500 RPM. Your final tuner will likely take a few percent out above 2500.
Most important, increase the tune's engine size to 6.2 Liters.
With the bigger engine and cam change you will have more power below 4500 RPM, smoother running, lower idle and better fuel economy.
As such I would add 10% fueling to everything below 1400 RPM and and less % at each RPM step above that until adding nothing at 2500 RPM. Your final tuner will likely take a few percent out above 2500.
Most important, increase the tune's engine size to 6.2 Liters.
With the bigger engine and cam change you will have more power below 4500 RPM, smoother running, lower idle and better fuel economy.
