Centering on a cell

Can you explain in more detail what it means to be centered in the cell you are making changes to, and what process it is to stay centered in that cell while making adjustments? I have my load and rpm tables set and base timing of 15 deg throughout the timing table. I assume you start in the 1500 RPM column because that is the first column outside of idle range. But i'm confused what you are doing to determine what the center of the cell is and how you maintain it.

Laurence

The center is literally where X and Y intersect on whatever table you're adjusting. Since you're talking about RPM vs Load it would depend on what you load identified as. For Alpha N it'd be as simple as setting your TPS (right foot) to a certain load point - lets say 50% - and RPM to 1500 (or wherever) and adjust from there. Speed density would be setting MAP v RPM et cetera.

How you get there is a different story altogether. If you're running a load bearing dyno generally just set and forget your speed, hunt for the desired load cell and you're good to go. If you're running an inertial dyno or some sort of (not recommended) street tune then you get to be your own load bearing device (left foot).

I will be tuning my Evo 8 with AEM Infinity using RPM and MAP as the X and Y axis for the fuel and ignition tables. I plan on renting time on either a Dynojet or Mustang dyno for steady state fuel and ignition tuning as well as ramp runs in order to tune at higher boost. I'm not sure how i will control speed while steady state tuning with either of those dynos though; hopefully the shop or tuner will lend a hand. This leads me into another question regarding steady state ignition tuning.

My turbo is significantly larger than a factory turbo and i will be using a 16 lb wastegate spring. The turbo is a 6466 which will start spooling around 4500 rpm. Should i tune steady state ignition throughout the rpm range or just go to 4000 rpm and then proceed with ramp runs? Also should i tighten up the resolution of the fuel and ignition tables in the 4000-5000 rpm range where i expect this turbo to build up to full boost? I noticed in a lot of the video examples the vehicle had a smaller turbo with the powerband shifted back a bit.

Thank you for the response and looking forward to more info.

Laurence

Last I checked Dynojet only offers inertial based products and by definition will not work as a stead state tuning device so, if it were me, I'd seek out a Mustang dyno and operator that'll let you rent time as well as actually operate the dyno. Ask them to config the dyno target to wherever you're trying to tune on your ride to give you maximum brain bandwidth tuning seeing as it seems like it'll be a first. With regards to your other questions, you're going to get the hated 'it depends' answer. Realistically you've got to get the config you're wanting to run stable and dial it in from there, it might want more resolution to tune out or around issues etc or, it also might be fine interpolating between large RPM points. It all depends on what the engine asks for.

Again, if it were me, I'd plan for a few dyno sessions seeing as you're in self admitted uncharted territory and creep up on it. You don't need to knock it out of the park the first time up at bat.

I have never operated a dyno or attempted tuning before. I'm going to break this up into at least a few sessions with some initial street tuning for the idle and cruise range of the fuel table. The car won't be ready for tuning for a couple months so I'm just gonna keep reviewing the basics and the Infinity videos until. Thanks for the response.

Laurence