There's another lengthy thread or 2 on here already about tuning the M4.4 six cylinder.
I swear I've searched for this particular scenario and not found much to sink my teeth into. Used google to search the site too.
240wagonguy said:
It's been said and done by a member, to just run the stock management with mild boost, turn up the fuel pressure a bit, change to larger injectors, and it's fine.
That's kinda where I'm at. Larger injectors and perhaps a MAF/larger housing to match. Rising rate FPR if needed to turn down the flow at idle/up for boost. Run a blend of gas and E85 to have a bit of overhead for the high compression and aggressive advance of the stock ignition. (cheapish) Electronic boost controller and of course AFR gauge.
Thinking about idle and bigger injectors.. based around the 25% trim limit in the 4.4. If you're keeping stock FP at idle, your injector choice would need to be below 266cc/min which is not really much above the stock 208 if you're looking to make power.
A combo that looks good is 329cc (T6) injectors at 25 PSI at idle (I'm estimating that based on 25PSI flow of 263cc/min at 80% DC). They should flow 363cc/min at 50PSI (again 80% DC). Rising rate for that was 2.5, putting it at 58psi at the rail... 50 at the injectors with 8psi of boost. A larger MAF housing might put things in adaptation range for idle, I won't know until I start testing.
I understand there's limited validity to these calcs because reality is dynamic. Without testing anything "in the wild" yet it's hard to say what the best combo will be... But that's my best guess.
The other thing I noticed is that according to VIDA, the stock fuel pump is only good
for 80l/hr at 43PSI. So if that's right, I'll have to get that swapped out before long, especially if there's ethanol added into the mix.
In my case, I'm not looking for massive gains, they won't happen with 10.7.1 anyway. But if I can make it a bit of a stump puller/lugger with a flat torque curve, that would make me happy.