HP Tuners Tutorials

[Gregski]

Volumetric Efficiency VE Table Calibration

So now that you have calibrated your MAF it is time to calibrate something called a VE table. Now for the record it really does not matter which you calibrate first, we can arm wrestle over it, but it don't matter.

Top Tip before we dive in. When tuning remember these simple marching orders: Same or better!

That's it, simple as that, we make changes hoping to make things better, they don't have to be perfect, just better. For example if your MAF was 15% out of whack on the lean side ie reading red or pink in the histogram graph, and you bumped it up so now it is only 10% lean, great job, you did it, that's an improvement. You can drive around for a week like that and regroup next weekend and bump it up another 5% if you like. That's what i mean by same or better, as long as you did not screw up and make it run 20% lean, you are following the same or better mantra.

OK, so Volumetric Efficiency table (pronounced: how well your engine breathes) is a table that shows in percentages how full your cylinders can get at certain RPM / engine loads.

It is important to dial this in because if you remember our GM engines rely on both the MAF and the VE table to calculate how much fuel to spray at any given time based on how much air is entering the engine. And the VE table corrects the MAF when need be so it ought to be accurate.

Time for another terrible analogy, ha ha.

It's January / February so new years resolutions are still in effect (let's hope). So you head off to the gym to meet with your personal trainer, aka the MAF sensor, ha ha. Tucked in under your arm is a clip board with today's exercises, aka the VE Table.

You approach the squat rack (it's always available as 99% of peeps there are there to do upper body or play with their iphones, sorry couldn't resist a gym joke)

You look at your trainer (MAF) and ask: "What are we doing today?" to which he (MAF) replies: "Three sets of 15 or as many as you can, I'll count the exact reps" [that's the MAF in action it will "measure" aka count the exact reps, just as the MAF measures the exact amount of air going in]

You following the trust but verify mentality embedded in you via this very Tutorial [ha ha] glance quickly at your clip board (ie VE Table) and go hmmm it says here:

Set 1: 135 lbs - 15 reps
Set 2: 185 lbs - 12 reps
Set 3: 205 lbs - 10 reps

and there you have it, that's sorta how the MAF and the VE table work together in conjuction, the MAF measures in real time, the VE Table holds a chart ie table of hard coded information.