Whats the difference between maf and speed density setups. Volumetric efficiency tables can be very time consuming to tune. Speed density is probably the most popular algorithm since with knowing map calibration, clt, iat and tps and injector flow rate we get a good enough tune without much tuning tuning would obviously be. Change maf to speed density mapbased air flow metering note.
We have had zero supported customers use blended mafmap. Speed density eec tuning guide this guide aims to provide tuning tips and method for tuning speed density sd or map sensor based eecs, i. Speed density map speed density uses the manifold pressure sensor map to measure the intake manifold pressure, then uses volumetric efficiency lookup tables indexed by engine speed to find the mass of air entering the engine. If you need a more general speed density tutorial, then the speed density 101 page may be what youre looking for. Aggressive cams produce little vacuum and therefor little for the map sensor to work with.
The speed density feature can be enabled in any of the map switch modes. Change maf to speed density map based air flow metering note. I show how to set the computer to default itself into speed density mode. Setting up 3 bar map sensor and wideband hp tuners bulletin board. Speed density vs maf igotasti is an online forum and community for all subaru wrx sti enthusiasts. Intake air temperature to determine load and last but not least to determine final. Gen iii speed density ve table and maf tuning instructions. Map only speed density requires performance tuning. Please feel free to contact us with any questions regarding this service. I forgot to mention that, i do plan on running speed density cause i dont. Tuning performance datalogging support for all mitsubishi subaru and nissan protocols. I also show how to disable other features into a completely defaulted tune file to use a base for adjust fuel. The maf is removed or disabled and the pcm is tuned using the map sensor.
This video tutorial shows the setup and tuning of the speed density system for. Sorry dont understand your 2nd sentence much but speed density tuning is where instead of the maf telling the vcm how much air its flowing, speed density is where it uses the map sensor to know how much pressure and what rpms your engine is running at and from there volumetric efficiency values are used to do the fueling. When calibrated properly there is no sacrifice in drive ability, your car will drive just like stock. In the forum you will find an informative tech area, a place for members journals, vendors with special members pricing, and monthly contests. Any of the three tuning softwares that we sell will work for this application.
Hp tuners ls3 e38 ecu flash service wiring specialties. This enhancement is a 2bar speed density enhancement. Speed density can be toggled in any map switch mode and a hybrid maf and. A few improvements and changes have been made in order to port it to the h8 ecus. Apr 08, 2015 how to tune a base map with hp tuners justin sane. Speeddensity is a method of estimating airflow into an engine in order to.
Speed density systems rely heavily on the reading from the manifold absolute pressure map sensor. The map editing software im writing will allow you to link cylinders so that if you add some fuel to one map of the set it. After logging for about 10 or 15 minutes you will have enough data to make your first changes, depending on whether you are using a maf sensor or running in speed density mode. Are the calibrations that come standard in the software speed density calibrations. The tuning approach differs but that is beyond what is needed to know to get your car setup for sd. Opening map run the accesstuner software, select the speed density checkbox, and select theecu of the car you are tuning. Ac compressor setting information program to generate ve equations old version program to generate ve equestions new version why is it no matter how lean i command my pe table my commanded afr doesnt. While i know there are sophisticated speeddensity systems out there, cars. Speed density can be toggled in any map switch modes, and a hybrid maf and speed density system can be implemented to aid accurate readings at low speed and provide maximum calibration at high power levels. Traction control adjust traction control characteristics. With sd we are using map for fueling so we cant go close to those limits. This is the fuel injection system that i prefer for aftermarket projects.
Speed density tuning using wideband o2 input by william henn. Please contact us if you have any questions on this. How to tune engine tuning 101 part 2 knock, fuel trims, map, maf explained duration. Why is there a map vs rpm and a tps vs rpm fuel map. Carberry rom 16bit speed density project attention tuners. This guide aims to provide tuning tips and method for tuning speed density sd or map sensor based eecs, i. This can be downloaded with tuning software so it is not critical to read your own ecm. Mass air flow and speed density are the two most common means of measuring how much air is being sucked into an engine, but whats the. Why do modern pcms prefer map over maf motor vehicle.
It is the map you adjust if you have some low rpm cruise around town hesitation or stumble. I can give a quick run down of what youd have to do to setup the tune for the turbospeed density. Speeddensity map speed density uses the manifold pressure sensor map to measure the intake manifold pressure, then uses volumetric efficiency lookup tables indexed by engine speed to find the mass of air entering the engine. Speed density is a must for those with high powered subarus or anyone that wants to use a vent to atmosphere blow off valve. The second chart to the right is designed to take a load value you would like to have at a given rpm vs map and gives you the appropriate speed density load calculation to use for that rpm map. Now the next step i usually do is drive the car around and look at the ltft long term fuel trim to see where in the map the engine is running lean or rich, and then adjust those. Used for tuning engines with large camshafts for forced induction. Simply open an existing mafbased calibration using the new speed density enabled software and resave the map. After installation, your gtr will take air temperature readings from the upper intercooler pipe rather than the factory maf housing.
This page describes the basic process for getting your car setup for speed density operation with ecmlink. Speed density tuning for fuel is using manifold pressure vs. Whats the difference between speed density and ve based. Gtr speed density kit install guide introduction welcome to the install guide for the visconti tuning r35 gtr speed density kit. Llc associates program, an affiliate advertising program designed to. If the ve table lookup for an engine running speed density is larger than the true ve of that engine at any given point, then the resulting airflow calculation will be higher than it should be and the resulting af mixture will be richer than intended as well because the ecu will inject more fuel than is required because its assuming theres. For information about tuning this area, see tuning part throttle fuel map high load fuel. Kit contents kit a sd harness driver side maf sensor block off connector charge pipe bank1 sensor lhdpassenger side rhddriver side kit b sd harness charge pipe bank1 sensor lhdpassenger side rhddriver side. Speed density allows tuning based on manifold absolute pressure map. Hit cancel with engine running and boost gauge showing. Productionbased speed density computers also utilize an oxygen o2 sensor mounted in the exhaust tract. Gen iii speed density ve table and maf tuning instructions with a wideband o2 sensor create by 69lt1bird jeff anderson 1 these instructions are written for the beginner and intermediate user of hp tuners software. Map sensors respond to changing conditions very quickly, enabling it to have fairly good transient response especially compared to massairflow. This means that we will not be using the maf sensor and will rely on the map sensor, as well as speed and other inputs, to calculate the fueling needs of the engine in any given state.
Help tuning speed density maps with romraider suzuki gsx. Most fuelinjected bikes utilize what is called a speed density system that estimates the amount of air flowing into the engine to determine the amount of fuel the engine needs based upon the rpm, ambient temp, the engines load the map or manifold absolute pressure sensor, and the throttle position the tps or throttle position sensor. Mass air flow and speed density are the two most common means of measuring how much air. The first chart uses your speed density load compensation chart and gives outputs the appropriate grev that you will be at at the given rpm vs.
Provides a secondary rpm and speed limit that you can program into your pcm. The calculator is capable of giving you the quadratic coefficients including blowthrough, with the goal being to hastensimplify the process of calibrating this model. Big thanks goes to him for coming up with the idea and starting it all. Infiniti vr30tt infiniti vr30 tuning complete guide. In this video, we cover manifold absolute pressure based tuning principles with the power commander 5 or cmd marine for tuning your forcedinduction engine. In other words you dont really need to tune the whole speed density map. Speed density map speed density systems map calculate the density of the air first by measuring the temperature of the inlet air and manifold pressure. Operating system enhancements with real time tuning rtt. Remember this rom uses manifold absolute pressure rather.
I opened up the tb induction because ill be putting on a 65 mm tb sooner or later but has a 58 now. With the density of air known the engine controller then looks up how much air it expects to bemoving at a specific engine speed and manifold pressure. If the manifold has volume x, and the map signal changes by y, during time interval t we can calculate the amount of additional airflow this represents and add it to the speed density calculation. Valet mode allows the driver to lock the car into a lower performance mode when lending it to a less experienced driver. Speed density map tuning and manual adjustments in hp tuners. The speed density calculation does not have this feature so we must recreate it so the ecu is happy and the car doesnt stumble. Available in the latest vcm suite beta is a new calculator for the ford speed density model. Ls why both maf and speed density general conversation. A range of activation options are available for engine speed, mass airflow or manifold pressure. Speed density tuning e40 pcms write up speed density tuning e37e38e67 pcms turned off your speed limiter but it still cuts out at 100mph.
This initial release of speed density is available for professional tuning shops using accesstuner pro software and for selftuners using accesstuner race software for the 20022005 subaru wrx offtheshelf maps will not be made available for speed density as custom calibration specific to each vehicle is. This region of the fuel table is used at high load and should be tuned to a safe airfuel ratio for maximum power. When i switch to ve based, the base fuel table says volumetric efficiency table %, but the actual table is still in lbhr. Speed density tuning using wideband o2 input by william. Speed density uses the manifold pressure sensor map to measure the intake manifold pressure, then uses volumetric efficiency lookup tables indexed by engine. Have you, or do you plan on building your gm lsxpowered vehicle with forced induction. I have put a lot of time and work into this rom and i believe this is a fair amount. My speed density system is based on the evo89 system written by jcsbanks. Jackal speed density tuning software for 1g dsms dsmtuners.
Speed density operation starts with the basic ideal gas law, which states the following relationship between gas air pressure, temperature and volume. A wideband o2 sensor is required for the tuning described in these procedures. I was told to use speed density calibrations with my intake that i have on my car. The o2 sensors adjust fuel below pe power enrichment, and above pe fuel is calculated from a table using the tps, map, rpm, etc. Anyone with speed density experiance willing to lend a hand would be much appreciated. The speed density sd system implements a volumetric efficiency map ve. Additionally, speed density systems need to be retuned every time you make a change to the engine. If so, youve probably heard about the 2bar and 3bar custom operating systems that hp tuners offers as an upgrade over the stock os thats limited to 1bar. Speed density tuning using wideband o2 input by william henn, foff667 speed density tuning using wideband o2 input.
Our kit includes a 4 bar t map sensor, plus our standard 4 bar gtr map sensor along with a factorylook wire harness. If you are using speed density mode no maf sensor, the easiest way to begin tuning fueling and geting the blms back to 128 is to run the log through. It utilizes every sensor except the maf mass air flow. This calculator is quite sophisticated, so an understanding of the process is vital to help get the best results from the calculator.
V8s use maf tuning, and are covered in another guide available at. Pressure sensors do not pose any restriction to the flow of air into the engine, unlike a maf sensor. In addition, the hybrid speed density feature offers a combined maf and sd configuration, the transition from maf to sd or sd to maf can be calibrated against a range of activation thresholds like engine speed, mass air flow or manifold pressure. Nov 15, 2018 with our camaros tune now open, it was time to upgrade it to a 3bar speed density tune. We have provided for this from a hardware standpoint, but i can tell you with 100% certainty we will be able to supported you better purely speed density. Discussion in general conversation started by ls won, aug 21, 2017. Our kit includes a 4 bar tmap sensor, plus our standard 4 bar gtr map sensor along with a factorylook wire harness. This region of the fuel table should be tuned to stoichiometry approx 14. Tuning a speed density system with mods now my concern is that the mods that i did may cause some problem with speed density. In order to make the transition to speed density as painless as possible, cobb tuning has streamlined the process within the accesstuner software. Another thing ive noticed is in load sensing, when i have it on speed density, it shows the base fuel table in lbhr.
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