Hybrid turbo upgrade selection & general tuning question

[Pete_89T2]

Originally Posted by FerociousP

Most likely yes. You need the capability to run larger injectors. This can be anything from an RTEK to maybe an S-AFC. ***Were you running more than 8psi w/o and FCD?***

Nope, I've been running the stock turbo at stock boost pressures, no FCD or any other mods to the stock ECU. My after market boost gauge has never read a *steady* pressure beyond 8 PSI with this turbo, but I've seen it spike up as high as 10~12 lbs for very brief instances.

With the stock ECU and boost control limits retained, I would assume boost pressure with the upgraded turbo would still be limited to stock levels - so I don't think I would ever be overboosting it. Also, this upgrade ports the wastegate, which in theory should make it less likely to overboost past the stock boost settings. The main concern I had is will the extra airflow volume that the stage 1 upgrade is capable of (at stock boost pressures) REQUIRE me to upgrade the fuel/EMS now, before adding the upgraded turbo, given that I'm not chasing after optimized HP numbers? Will running with the stock ECU (and its AFR mappings) cause me to go a bit lean under boost, which is possible given the additional airflow volume, and potentially grenade my engine with this turbo? From what I've read, the Mazda stock ECU mappings run pretty rich, and there may be enough of a factor of safety in there to accomodate a turbo that flows just a little more air than stock, at the same boost pressures.