The Quick Answer
VAST isn’t just a tune—it’s ongoing support, custom datalogging, and expertise built on 10 years of Volvo tuning experience and over 900 cars tuned worldwide.
Knowledge, Experience & Customer Support
At VAST, we’ve been tuning Volvos for 11 years, with 7 of those as a full-time profession. We’ve spent thousands of hours not only tuning, but also rewriting, coding, and optimizing the factory engine management for 92-98 Volvos.
- 900+ cars tuned in 30+ countries
- Hand-built many high-performance Volvos over 450 WHP
- Deep expertise in M4.3/M4.4 engine management systems
How We’re Different from Off-the-Shelf Tunes
Off-the-shelf tunes from companies like IPD, Speedtuning, or MTE are simple remaps based on dyno tuning of one or only a few cars—by someone with only a cursory knowledge of M4.4. When you purchase from those companies, all you get is an ECU with a bottled tune. There’s no support if your car doesn’t perform to the advertised goals.
With VAST, you get:
- An in-depth diagnostic overview of your car through datalogging
- The expertise of someone who has been tuning for years
- A tune optimized specifically for your car
Every Car is Different
Over the years, we’ve realized there’s huge variability between cars. Two cars with the same modifications on paper can perform drastically differently—one might safely push 20+ psi while another can only make 12 psi.
With a VAST tune, you’ll get the most power your car can safely make. No compromise between “aggressiveness” of the tune and longevity of the engine.
Customer Support That Goes the Distance
When you buy a VAST tune, you’re not just getting software—you’re getting me. I work directly with every customer, not only helping them tune their cars, but also troubleshooting issues that prevent their car from running as well as it can.
I’ve exchanged up to 300 emails with some customers. Whether it’s dialing in your tune, chasing down an air leak, or diagnosing a weird idle issue, I’m here to help you get your car running right.
Example: What VAST Support Looks Like
Here’s an actual email I sent to a customer after reviewing their datalog:
For the most part, this log looks good. However, your long term fuel trims are a bit off, most likely indicating an air leak.
Using the oxygen sensor, the ECU has a feedback system to determine if the engine is running the correct air to fuel ratio (AFR). For emissions reasons, the target AFR during light engine loads is 14.7 parts air to 1 part fuel, or 14.7:1. All of the calibrations related to fueling in the tune are configured so that the fuel injectors deliver the correct amount of fuel to achieve this target. However, since the engine isn’t running under perfectly ideal conditions at all times, the ECU dynamically adjusts injector open time so the target AFR can be met exactly.
M4.4 uses 3 values to keep the AFR as close as possible to 14.7: short term fuel trim (STFT), long term fuel trim at idle (LTFT_I), and long term fuel trim at part load (LTFT_PL)…
Under ideal conditions, both LTFTs should be 0 and STFT should vary between ±10%. In the real world, I usually shoot for LTFT_I < ±50 µs, LTFT_PL < ±8%, and STFT average deviation < ±15%. At the end of your log, your LTFT_I was 148µs and your LTFT_PL was -10.94%. Both out of spec, but not hugely so.
A good way to know if you have an air leak or faulty MAF is to look at idle air mass. When warm (coolant >82°C), idling at 840 RPM in neutral, the engine should consume 14.5 kg/hr. Your log showed ~11.6 kg/hr—about 20% lower than it should be.
To find air leaks, start with a visual inspection of all charge air pipes and vacuum lines. Usually a pressurized leak test is the only surefire way to find all leaks…
If you haven’t already, I recommend replacing all vacuum lines in the engine bay with silicone. You can get an assortment kit on Amazon for pretty cheap.
Once you go over everything and fix any issues you find, collect another log and email it to me.
This is the level of detail and support you can expect with every VAST tune.
Datalogging
The main focal point of VAST tuning is datalogging. The datalogging routine on every VAST ECU is a custom, non-stock routine that allows acquisition of literally any ECU parameter at 20-25 samples per second.
What you can see:
- Knock detection on a cylinder-by-cylinder basis
- Boost pressure
- Coolant temperature
- Airflow
- And many more parameters
See Available Datalogging Parameters for the full list.
Why OBDII Datalogging Doesn’t Cut It
Other “tuners” offer datalogging via OBDII. For M4.4, OBDII datalogging is functionally useless:
- Maximum of only 3 variables
- Meager 1-2 samples per second
- Add more variables and the sample rate drops even further
For a complete explanation, see Datalogging, and Why VAST Does It Best.
Every Tune is M4.4
Every tune we provide uses M4.4 (Motronic 4.4)—an incremental upgrade over the M4.3 engine management system on 850s. M4.4 originally came stock on 1998 V70s, C70s, and V70 XCs, but it’s backwards compatible with M4.3 cars when programmed with the correct software.
M4.4 advantages:
- Twice the program memory of M4.3
- Higher resolution maps
- More complex operating routines
- Quicker starting and smoother running
The necessary software modifications to make M4.4 compatible with your M4.3 car are provided free of charge.
Additional Features
Boost By Gear (Manual Transmissions)
For manual tunes, VAST offers boost by gear—4 separate boost maps: individual maps for gears 1-3 and one for 4th/5th gear. Burning out can be fun, but it’s not the fastest way to accelerate. These maps limit boost to match your available traction.
On-the-Fly Map Switching
Map switching lets you switch between two different ECU map sets on the fly. Want to run E85 on a track day? Simply depress the accelerator pedal before starting the car to switch maps.
Assistive Troubleshooting
OBDII codes typically need a run cycle to set—so a faulty sensor preventing your car from starting usually won’t trigger a code. VAST’s datalogging routine lets you see 83 error-bits that are set as soon as the ECU detects an error (usually instantaneously). This makes diagnosing no-start issues a cinch.
Check Engine Light Flash During Knock
One of the most important software additions: the ECU will actively flash the check engine light in response to actual, detected knock. You’ll know immediately if the engine is experiencing pre-ignition.
Wideband Datalogging
The rear O2 input has been repurposed to collect information from a wideband controller. Most modern widebands have a 0-5V analog output that can be wired into the old rear O2 connector. This lets the ECU datalog wideband AFR in sync with all other parameters—greatly assisting in proper tuning.
Boost Datalogging
Stock M4.4 has no way to directly measure boost. Every VAST ECU comes with a MAP (manifold absolute pressure) sensor installed, allowing the ECU to log manifold pressure alongside all other parameters.
Low Voltage In-Situ Programming
Your ECU is modified at both hardware and software levels for datalogging and in-situ programming. The switch on top toggles “bootloader mode” for receiving new tune files. Unlike other ECUs, no battery charger is needed—reflashing works at as low as 11.8V system voltage.