Tuning Blog

Pros and Cons of E85 February 06 2018

So what's the deal with E85? Import enthusiasts often wonder whether E85 is right for their car, and we'd like to present a few points here to help clarify the pros and cons of using E85 in your turbocharged motor.


  1. Greater detonation resistance. Ethanol (ethyl alcohol) blends are typically 100+ (RON+MON)/2 (pump octane rating) which allows Peak Cylinder Pressure (PCP) to be placed more optimally safely, which means more power. To elaborate a bit more, part of the reason for the better detonation resistance is that ethanol burns clean and distributes evenly under lower lambda (rich, i.e. < 12 AFR). This leaves less chance for secondary combustibles being left in the combustion chamber after the initial combustion event, thus decreasing the chance of detonation. The cleaner the burn and the more uniform the air/fuel distribution, the less chance for detonation. Less chance of detonation directly leads to the ability to more aggressively place PCP by running a leaner mixture and/or advancing ignition timing, thus increasing torque output on the piston down stroke. This also means you can run more boost if your turbocharger will allow for it.
  2. Latent heat of vaporization.Ethanol has a much higher latent heat than gasoline which allows it to absorb more heat out of the intake charge when it phase changes from a liquid to a gas, effectively increasing charge density and therefore directly increasing power and lowering the chance of detonation due to lower combustion chamber temperatures.
  3. More efficient burn at lower lambda. At 0.8 lambda, a high-percentage ethanol mix burns much more efficiently than a 0.8 lambda gasoline mix (~11.8 AFR). Gasoline burns relatively "dirty" or inefficiently at richer AFR's that are of course a necessity on turbocharged vehicles. This again means more power can be produced on ethanol at the same lambda ratio while still maintaining safe EGT's.
  4. Same effective energy potential as gasoline. Although E85 is often cited as having less energy content per unit volume as gasoline -  which is absolutely true - it does have about the same effective potential energy when it is run at the same lambda ratio as gasoline. That is, a 7.8 AFR mix of E85 and air has about the same energy potential as a 11.8 AFR mix of gasoline and air - both at an equivalent 0.8 lambda ratio.
  5. Safe for your fuel lines, gas tank, and engine seals.Contrary to popular belief, ethanol based fuels are safe to use on ALL modern vehicles as far as your fuel system is concerned. Yes, ethanol is corrosive but so is gasoline. Care must be taken with certain components such as fuel pump pickup socks and fuel filters, but your fuel lines, gas tank, and seals are all safe for use with ethanol from the factory.



  1. Less fuel efficient. Because ethanol has a much lower or richer stoichiometric burn ratio than gasoline (9.8 vs 14.7) , it effectively requires about 30% more fuel to maintain a 1.0 lambda ratio (14.7 AFR). This means about a 30% drop in fuel economy, a little of which is recovered due to E85's ability to be run safely at a higher lambda ratio (leaner) than gasoline and its ability to produce better power under all conditions after PCP has been more optimally placed by advancing ignition timing.
  2. More fuel system capacity required. Due to the above point, E85 also requires about an extra 30% capacity in your fuel system. This means that if you were running > 80% Injector Duty Cycle (IDC) on 1000 cc/min injectors before, you will now require at least 1300 cc/min injectors. It also means that you will need a higher flow fuel pump as well - often even a Walbro 255 L/hr pump isn't enough to make big power on E85.
  3. More difficult to find. In most areas outside of the Midwest, E85 pumps are few and far between. The additional travel time needed to source ethanol-based fuel turns many people away from using it. Consider yourself lucky if you have an E85 station close by!
  4. The standards for "E85" are very broad and can result in the actual ethanol mixture at your local pump varying from 65% to 85%. Luckily, the ethanol content variance is less than that in a particular region, but due to the need for increased fuel volatility in the winter, ethanol percentage must be dropped across the board. Unless your tuner is very deliberate with your E85 tune, your motor will run lean in the summer if it was tuned in the winter and it will run rich in the winter if it was tuned in the summer. Ideally, fuel scaling values should be adjusted to a "sweet spot" right in the middle of the actual E85 mixture range in your area, and on cars like the Evo X the tune can be set up to allow Long Term Fuel Trim (LTFT) to affect full throttle operation to be able to compensate for ethanol percentage changes.
  5. HygroscopyWe've got to go back to chemistry 101 for a bit to explain this one, but suffice it to say that ethanol is a very hygroscopic compound, meaning that it readily attracts water molecules from its environment. Because of this, any time it is exposed to air, it very rapidly pulls moisture out of the air and into itself. This is a problem in fuel injected cars because certain components in your fuel injectors contain high percentages of iron and therefore will rust when exposed to water. More details from Injector Dynamics here: http://www.injectordynamics.com/AlcoholArticle.html

To sum it all up, E85 has clear benefits to making more power, but it does have several downsides. If you often feel the need for speed like we do, it is definitely worth looking into! With true flex fuel tuning capabilities on Subaru, Mitsubishi, and many other platforms, now is a better time than ever to make the switch.

Why Injector Characterization Data and Dynamic Matching Are Important May 06 2016

With seemingly dozens of aftermarket performance fuel injector companies popping up every year, I feel it important to explain why I recommend certain injectors above all others. It's no secret that tuners love Injector Dynamics (ID) injectors, but why is that? Let's take a quick look at the factors most people consider when choosing injectors for their high performance builds.

Impedance (High-Z / Low-Z)
The starting point for selecting applicable injectors for your vehicle - at least in the past - has always been impedance. There are two categories of injectors that appear in OEM applications: high impedance (saturated) and low impedance (peak-and-hold). Suffice it to say, low impedance injectors dominated the high-specific-output import tuning scene 5+ years ago due to higher available flow rates. This all changed when injector manufacturers (such as Bosch and Denso) started producing affordable high impedance injectors with flow capacities well beyond 500 cc/min that could be modified with relative ease to much higher flow rates.

Generally speaking, enthusiasts and tuners chose injectors that matched the impedance of a vehicle's stock injectors so that resistor packs did not need to be removed or added in order for the injectors to operate correctly with the ECM's internal injector driver circuits. In recent years, tuners have been employing high impedance injectors on almost all cars, mainly due to higher available flow rates, better quality, and cheaper prices.

Flow Rate
After sorting out the high-Z vs. low-Z business, we usually move on to select a set of injectors for their maximum advertised flow rate. Most manufacturers publish a simple cc/min (volume based flow) or lb/min (mass based flow) figure such as 1100 cc/min or 90# injectors (implies 90 lb/hr). This flow rate is usually determined at 43.5 PSI (3 bar) fuel rail pressure and under static conditions (that is, the injector is fully open at 100% duty cycle).

There is usually little data to back up these flow rate figures as they are derived from injector flow testing techniques that even many local automotive repair facilities use. So from the maximum advertised flow rate, we can determine that the injector will meet our fueling needs after crunching a few numbers, right? Not exactly... but we'll get to that shortly.

Anecdotal Reviews
First-hand experience carries quite a bit of weight on Internet message boards/forums where people discuss automotive modification and tuning. So when Joe Schmoe with a 500 WHP Evo or STi says these injectors work GREAT, it makes sense to believe him, right? After all, injectors are just simple electronic solenoids that squirt fuel out under pressure - how different could they possibly be?

The answer is - ironically - not very different. Given a reputable aftermarket injector manufacturer like RC Engineering, Fuel Injector Clinic (FIC), ASNU, Injector Dynamics (ID), or DeatschWerks (DW), the product you're getting is fairly well machined and flow matched for the advertised maximum flow rate. There are subtle differences in technique and quality, but all of these injectors operate pretty much the same way: the ECU closes the injector circuit during the intake cycle of 1 cylinder for a pre-determined pulsewidth with a latency compensation adder, the solenoid sprays pressurized fuel into the intake tract, and combustion proceeds as planned.

If this is true, why do many specialty tuning shops like WTF prefer one injector over another? I'll tell you right now it's not uneducated bias; I've used pretty much every injector on the market in tuning over the past 10 years and they all can be made to work pretty well given varying levels of calibration effort. So what is it that makes an injector more than just "OK?"

Typical Injector Specs
Let's look at what you get with a typical set of injectors - if you're lucky - to guide you or your tuner in getting your car to run well:

[Image: A3g2cyg.jpg]

[Image: 3BLELk4.jpg]

So this seems like adequate data to get your car running well. In some cases, you'd be right. Given a few hours of effort, this injector data will allow a tuner to get your car starting, idling, cruising, and accelerating at WOT well under most conditions. However, the lack of knowing what the injectors flow at 5%, 10%, 50%, or 60% duty cycle will leave much work to get your motor running at the correct lambda (AFR) at the load points between WOT and idle. Injectors also start to behave unpredictably (that is, in a non-linear fashion) at low pulsewidths - below 1.5-2 ms or so. Not knowing how the injectors behave at low pulsewidths and just performing guesswork, leaving the factory low pulsewidth calibration intact, can result in very undesirable hunting, stalling, or misfire issues at idle.

Often tuners tune around many tables that the factory calibration engineers painstakingly populated for near-perfect drivability in all conditions, instead of using these tables to their advantage. Due to the nature of closed loop (PID control) fueling in modern fuel-injected cars, a lack of a factory-quality calibration is often masked. The problem is, given the standard set of data in the example tables above, a tuner has no idea whatsoever how the injectors actually behave in real-world usage. This is where a proper set of characterization data can save not only time in tuning, but also provide a much better end product.

Going Above the Norm
At this point in the article, I bet you're wondering where this is going. Well, as it turns out, there is at least 1 injector manufacturer that has collected enough empirical data about their injectors to publish detailed characterization data: Injector Dynamics.

ID go beyond just providing some bench flow rates and a simple latency compensation table (which from other injector companies is often derived from the calibration of a particular vehicle with the injectors, instead of out of the car using laboratory-grade equipment). Instead of giving some maximum injector flow rates at 1 set pressure, they have published full flow curves of their injectors at many different operating pressures: ID1300 injector data (scroll down to see more pressures). If you scroll down on that page a little further, ID also provides data on injector behavior at low pulsewidths - which leads to a better idle under all conditions as well as more consistent behavior during deceleration conditions. These two critical sets of data allow a tuner to fully calibrate a factory ECM or a standalone ECU to the specific set of injectors instead of relying on the default or factory calibration. (Note: ID data is now tabulated in vehicle-specific format. Evo X characterization data is coming soon)

This characterization data not only provides utility to a tuner, its painstaking collection proves that the injectors behave in a particular manner, and it provides a means to validate that injectors behave according to their intended engineering specifications. Given that your ECM is programmed according to the published characterization data from ID, it provides a solid basis or model of the injectors' behavior. On the Evo X, this means that a intake can be tuned independently from your injectors without one model unintentionally influencing the other.

It also provides confidence for a tuner to identify abnormalities in behavior of your fuel or load-metering system. On any other set of injectors, coming across and diagnosing a fuel delivery problem involves a ton of guess-work. When your tuner is able to be confident that your injectors behave exactly as portrayed by their characterization data, it gives the ability to not tune faster and easier, but also to diagnose problems quicker. Ask any reputable tuner how many Injector Dynamics injectors they've seen behave contrary to the published specs, and the answer will be clear. Ask the same about FIC or DW injectors, and you'll hear a lot of horror stories.

Another process exclusive to Injector Dynamics is dynamic matching. From the competition, injectors are matched at static flow (100% IDC, or fully energized or opened) and - if you're lucky - one other pulse width. Injector Dynamics not only characterizes their injectors at different pulse widths or operating ranges, but they also match them into sets at various pulsewidths from 2 ms to fully-open. Injectors that are unable to be matched and grouped into sets within reasonable tolerances (a couple percent) are discarded. This ensures that every injector in your set will behave as intended, no matter whether your engine is idling, cruising at a steady state, lightly accelerating, powering up a hill, or fully WOT. Under any condition, and given that your injectors have been protected from particulate debris, this means every cylinder will be running at the targeted AFR or burn ratio; not one too rich, nor too lean.

What this means for you & your car
With injector characterization data such as provided by Injector Dynamics, guaranteed dynamic matching, and the utilization of proper tuning technique, this is what you as a customer will get:

  • Better and more consistent drivability overall
  • A more consistent idle under all conditions (even with the A/C and/or various other accessories on) - no stalling, no hunting for the correct stoichiometric AFR (14.7 on gasoline), no rough idling or rhythmic popping from an unexpected rich or lean condition on one or more cylinders
  • Fewer swings in fueling as your ECU's closed loop system battles with a poor fuel calibration - this can usually be felt as slight surging or "dead spots" during light acceleration
  • More of your hard-earned money can pay your tuner to achieve more optimal timing and fueling calibrations for better fuel economy and maximized power output, instead of paying them to wrestle with the ECU to get fueling "just right."
  • Peace of mind that your injectors are well-matched at all operating ranges, never leaving any cylinder in your engine running too rich nor too lean

With all of this in mind, please remember these advantages when selecting your next set of injectors. Make sure your tuner understands the importance of proper injector characterization data and dynamic matching, and that they know that you are aware of the difference it can make. If you have any questions about injectors, tuning, or want to schedule an appointment to let me tune your car, please shoot me a PM on this forum.

More reading material from Injector Dynamics:

And an awesome video:

WTF Is Going Full Time! April 13 2016

It's true... since the beginning of the year, we've been planning the transition to moving WTF into a fully fledged shop. TJ has even left his day job as a Java engineering consultant to be fully available for your wrenching and tuning needs!

With a team of four dedicated automotive enthusiasts here to help you with all of your parts and performance needs, you'll love your new clear choice for getting work done on your Evo X or Ralliart.

Our pricing is reasonable, and we guarantee all of our work with the utmost of confidence. Don't chance your prized Evo or Ralliart with just anybody. Bring it to folks that have done every conceivable thing to these cars dozens of times and who pride themselves on perfection and technical expertise.

Let our 7+ years of experience on this platform and our impeccable attention to detail minimize your downtime and put your mind at ease when caring for and upgrading your beloved Mitsubishi!

We'll be offering the following at our shop:

Basic Maintenance

  • Oil & filter changes
  • Used oil analysis
  • Air filter and cabin filter maintenance
  • Drivetrain fluid service (transmission - SST & 5MT, transfer case, and rear diff)
  • Coolant changes and flushes
  • A/C recharge and diagnosis
  • Spark plug inspection and replacement
  • Boost leak testing and repair
  • Compression and leak-down testing
  • Timing chain inspection and replacement
  • Oil pan repair and replacement
  • Engine diagnostics

Drivetrain Maintenance and Upgrades

  • ACD/AYC bleeding and fluid replacement
  • 5MT clutch replacement and upgrades
  • SST clutch replacement and upgrades
  • Transmission service and replacement (SST & 5MT)
  • Transfer case service and replacement
  • Rear differential service and replacement
  • Driveshaft replacement
  • Shifter bushing upgrades
  • Drivetrain bushing upgrades (driveshaft & rear diff)
  • SST teach-in & diagnostics

Engine Upgrades

  • Injector installation
  • Fuel system builds & installation (surge tanks, filters, FPR & fuel lines)
  • Intake installation
  • Intercooler installation
  • Charge piping installation (UICP & LICP)
  • Diverter valve installation and setup
  • Exhaust manifold repair and installation
  • Turbocharger repair and installation
  • Intake manifold installation
  • Catback exhaust installation
  • Downpipe installation
  • Test pipe & HFC installation (off-road use only)
  • Exhaust repairs and modifications (proper TIG welded repairs)
  • On-car upgraded camshaft installation
  • On-car valve spring installation
  • Fully blueprinted engine builds
  • Block sleeving

 Suspension, Brakes & Body

  • Brake pad replacement
  • Brake fluid exchange & bleeding
  • Brake line upgrades
  • Big brake kit upgrades
  • Front lip and splitter installation
  • Lowering spring installation
  • Coilover installation and set up
  • Anti-sway bar installation and set up (front & rear)
  • Upgraded bushing installation
  • Roll-center adjustment kit installation
  • Ball joint replacement
  • Tie rod end replacement
  • Power steering service

And of course, in-person dyno tuning services at our partner location will still be available.

Driven Fab EVO X Air Oil Separator and 3" Intake Install January 07 2016

Ryan Reynolds

Last night we replaced TJ's puke-filled, top-mount catch can and ETS intake with Driven Fabrication's bottom-mounted oil-separator and air intake system.  For $299 ea. this combo is affordable and well made, coming with all the fittings and plumbing that sits nicely in the X's engine bay.  If you want to take a look, you can find them on DF's website here and here.

We started by removing the original catch-can and air intake system.

removing ems intake

After lifting the vehicle, removing 25lbs of under skirting ( sigh ), we removed the 12mm ground wire and bracket bolts required for the new CC mount.

Next, we noticed a small amount of machine dust and hamburger grease on the new plumbing. This was quickly removed with brake cleaner and the help of a compressor nozzle. Don't let this dissuade you as the construction and finish of the CC is very well executed.

catch can internals

We ran in to a problem mounting the CC; a pesky bracket prevented us from getting the CC fully inside the bay.  Removing this was easy and the component doesn't seem to have any structural value ( safety 3rd ).

useless bracket

The next problem we encountered was attempting to insert the CC with the oil filter hoses attached.  Removing these allowed us to get the CC and mount in from underneath the engine bay.  Additionally, in hindsight, we should have fully tightened the top intake tube down fully before mounting ( 12 AN ).  Getting to this from up top didn't leave much clearance to tighten.  Also note that, after mounting, ensure the CC bracket is perfectly square to relative components as it makes mounting the hoses much easier. Stripping these sexy AN fittings out will ruin your day real quick.

tj install from bottom 

Once mounted, attaching the lines is fairly straightforward and we didn't observe any problems with clearance or tubing length.  Having a friend help negotiate the lines from the top, while feeding from the bottom, seemed to be the easiest method of plumbing.

cc mounted

Connecting the breather tubes is straightforward, there's really only one obvious option to route each of the tubes.  See the after photo for final fitment with intake.

Adding the intake was fairly straightforward.  The fitment was near perfect.  The only issue we had was some residual residue leftover from the manufacturing process that was cleaned up via brake cleaner and compressed air.

We did note that placing the coupler on the turbo first, then attaching the intake made a quick fit.  All-in-all it fit perfectly with the CC plumbing.

After all said and done, the project took approx. 3.5 hours. It would have been less but TJ had a movement. He's on a newage diet.

We'll update when we've put a few miles on it and emptied it. We expect less stink and less atmospheric condensation from the lower mounting location compared to the engine bay CC it replaced.

Common Dyno Myths Dispelled :­ Road Tuning vs. Dyno Tuning June 16 2015

Myth: Road tunes are better than dyno tunes because they more adequately represent real-
world conditions.

Truth: Most calibration­-grade automotive dynamometers (dynos) provide a mechanism to simulate not only real vehicle weight, but wind resistance as well.

At WTF, we use a Mustang Dyno unit capable of absorbing up to 900 horsepower worth of simulated wind resistance and vehicle­-weight­-based inertia thanks to an electromagnetic eddy current power absorber/brake. What this means is that our dyno not only can simulate vehicle weight and aerodynamics, but it can also simulate hills of varying grades and can even hold RPM at a steady state regardless of the amount of power applied. These capabilities have proven invaluable to constructing factory ­quality tunes.

Myth: A dyno tune only consists of tuning for peak power output.

Truth: A good dyno tuner will tune for factory-­like accuracy in fueling, optimized fuel economy, as well as optimal peak power under all conditions.

We don't just spend time tuning your car for numbers at WTF; in fact, our tuners spend most of their time on the dyno ensuring your vehicle has as close ­to ­stock driveability as possible. We are intimately familiar with how ECU's/ECM's are calibrated at the factory and our #1 goal is to leverage the models programmed in your ECM by the factory engineers instead of working around them. This is also one of the reasons we are so concerned with the health and viability of your motor and forced induction setup before putting your car up on the dyno. If there are mechanical deficiencies such as compression imbalance or boost leaks in your engine bay, it will greatly affect our ability to correctly remap your factory ECM's fueling model to match your carefully­-chosen modifications.

Myth: After a dyno tune, your AFR (lambda) readings will drift rich or lean on the street at WOT.

Truth: An experienced ECM calibrator with access to a proper load­-bearing dyno with appropriate amounts of airflow will produce for you a tune that behaves correctly both on the dyno and on the street.

On non­-load-­bearing dynos (such as Dynojet and Land & Sea (DYNO­mite) units with no eddy brake units installed), this is a very real issue. Because tuners are limited to applying only the weight of the dyno roller(s) against your car's powertrain, often insufficient load is simulated which leads to overly rich AFR's on the street. As covered above, this is one of the many reasons we have chosen a load-bearing dyno like the Mustang Dyno for doing factory-­quality calibrations.

There is partial truth to this even on eddy current dynos like ours, but it usually stems from inadequate airflow on the dyno leading to inaccuracies in remapping of the load and fuel calculation models of your ECM. Every modern ECU/ECM has compensation mechanisms for intake temperature, but often these aren't enough to combat differences in ambient airflow on the dyno vs. at 60+ MPH on the road. Our tuners spends several hours a week researching about factory ECM calibration techniques, and we all are constantly learning and adopting new approaches to help put us in the same mindset as the team of engineers who painstakingly calibrated your car's engine electronics at the factory.


In summary, a good dyno tune will always be superior to a road tune. As a tool, it allows for repeatable results that just aren't possible on the street. Although the cost of dyno time may seem high compared to being able to tune for "free" on a road, ultimately dyno tuning provides a safer environment for tuning where there is no fear of speeding infractions or potential of having your car impounded while street tuning at high speeds.


Say hello to 4B11 parts done right October 24 2014

Here at Wasatch Turbo Factory, we pride ourselves in developing and practicing the best tuning techniques in the world for the 4B11 platform. But did you know we are developing hard parts for your car now, too?

Thanks to the input and feedback of the best-of-the-best in the Evo X tuning world, we are pleased to announce that Wasatch Turbo Factory are now producing small batches of superior, quality products for your car. Look forward to custom fuel line assemblies, engine bay dress-up pieces, custom hydraulic lines (P/S, ACD/AYC), and much, much more!

Follow our research and progress here: http://www.boostedforum.com/