Best affordable Fuel Mangement
- Thread starter silentdaredevil
- Start date
how so? all i need it for is to control the bigger injectorsEran said:safc's are the most low-brow, degraded form of tuning you can do ....
piggy back or not it still does what i need it to do correct?
also vtec engagements/disengagements, advance/retard timing, launch control, and rev limiters.io_303 said:
did you get a bigger fuel pump?silentdaredevil said:
heres something from hondaswap
The most important part of the system is the ecu. Ultimately, the ecu is what controls the car. It gives when needed, it takes when not needed. But the brain can only be as good as its "eyes" are- the sensors. If it 'sees' a wrong value, it's going to throw out a bad response. For this reason, among others, it is important to keep your ecu error-code free and all your sensors in proper working order.
The problem with boosting a honda is that from the factory, the computer is not designed with boost tables for fuel or ignition. After it sees about 2 or 3 psi of positive pressure, it will throw a code for the map sensor and send you into limp mode. The reason it has SOME positive boost pressure capabilty is that at 0 psi and 0 vacuum, depending on elevation it will go a little over at times. The 0 map will be suffice for 2 psi, so it allows it. But after that, it slams on the brakes to prevent you from damaging the motor and runs its limp mode program which will cut timing and a lot of your power.
When you turbo your honda you need some way to get around this.
There are 3 ways-
Block it
Trick it
Alter it to read it
Blocking it is the cheap route, and also is the worst option. This method is used when you run an fmu and a missing-link system. The FMU provides the extra fuel by raising the rail pressure, needed to account for the extra air. The ecu's fuel map is not used other than it normally would be for all motor. Thus, you're relaying on exactly the FMU's, say, 12:1 raise in pressure for every psi of boost you throw at it. The missing link works with this, in that it blocks the ECU from ever seeing positive boost pressure. All it is is a check valve. It will let a certain extent go through, and vacuum is unchanged. But once it reaches positive pressure, it blocks the map sensor from reading anymore. The ecu never even knows that you boosted. This method is good for low power applications. 6psi on a larger turbo, 8-10 on a dinky turbo
Tricking it is a little more complex, but ultimately results in the same results. This method is accomplished when you use what's known as the VAFC Hack. Pioneered by Liam Slusser and found out by total accident, the hack is a mothod of tricking the map sensor into not reading boost. The stock honda map sensor is 1.8 bar for obd1 and 2 vehicles, and slightly less for obd0, giving the map the ability to READ up to 10.6 or 9.8 psi respectively. Now, remember, just because the MAP sensor can read it and convert it to a voltage does NOT mean that the Honda computer knows what the heck to do with it when it's out of its range. When running the hack, you use a set of large injectors, such as 440 or the popular DSM 450cc's. At idel, without control, these almost double the stock 240cc injectors would flood, stall, and wash out the cylinder walls of your motor. Using a VAFC, you can tune them down. Start at, say -40% at 1000 rpms and working your way up adding where fuel is needed. (This is an example only. be sure to tune your car on the dyno with a wideband o2.) The real trick comes in because of how the vafc is hooked up. It is wired to the map signal wire. When the vafc is tuned down low, it being a piggy back device, sends the altered readind to the computer. The computer thinks you are not in boost because it isn't reading it. This method is good for about 10psi. After that, not only are you approaching topping out the map sensor's reading range, you're about to throw a code on the ecu. The main disadvantge of this setup is that it does nothing to alter ignition timing. There's a LOT of power to be made or lost in ignition timing.
The 3rd, and best method is to either Alter the ECU to be able to read boost or to replace the ecu with one that can. Hondata, Uberdata, FAST, Haltec, AEM EMS, and tons of others use this method. Hondata and Uberdata allow a chip to be placed into a socket on the stock ecu which can be programmed to read boost. Even more so, They all allow for more map positions.
For example,
QUOTE(hondata.com)
The Honda ECU has two ignition and two fuel tables, so that there are separate tables for the low and high speed cams. Each table is divided into rows and columns, with engine revs being indexed by row and engine load indexed by column. Hondata expands the factory table size to allow additional columns for boost. Typically the factory 20 x 10 tables are expanded to 20 x 16 cells for the low cam and 24 by 16 cells. This provides 704 tuning positions...
Try doing that with your FMU or vafc hack.
The cost is steep, but the benefits are great and easy to achieve with a tuner behind the laptop. The only way to make big power is with a good computer system. Hondata supports 3-bar map sensors. AEM supports 3.5bar or 5-bar. the 10 psi 'limit' has now jumped to 28, 33, or 55 respectively. Remember, 1 bar = 14.5 psi and the atmosphereic pressure is 1 bar already. For example, a 5-bar map leaves you 4-bars of boost to play with.
Which ever method you are using, you are going to need to get more fuel into the motor.
If you're running an fmu, install a walbro 255 pump in the tank. Inline boosters are the same price or even more money and still rely ultimately on the stock fuel pump. Theres no reason not to use an intank from the get-go. The pump is really the only component you need with the fmu/missing link set up.
If you're running the VAFC Hack, you will need the pump above, larger injectors, and of course the vafc. RC makes saturated 440cc injectors and will not require a resistor box. If you use a peak/hold style injector on an obd1/2 car, you will need to wire in a resistor box from an obd0 honda or some sort of inline resistor that will provide the correct features. Getting into this is off topic for this post. Going larger than 450cc is not recommended. The VAFC simply can't tune them down enough, and will provide for some at-idle flooding.
If you have the bosst-readable ecu, you're options are endless. From running a setup like above with just a pump with 440s all the way up to external wetsump pumps on an in-trunk fuel cell, -6an feed lines, 1600cc injectors, and 5-bar map sensors and every stop inbetween.
An important point to make is that without some very crazy modifications that I don't have a clue how to do, you CANNOT run a larger than stock map sensor on your stock computer. The reason is because all map sensors, 1, or 5 bar, all operate on a specific voltage range- most likely 0 to 5 volts. 0 is full vacuum range of the sensor and 5 is full boost range of the sensor. As you can see, when the sensor can read 5 bars, and is still throwing the ecu 5 volts, the stock computer thinks its the stock map sensor's 5-volt reading. All standalones that support different map sensor sizes have settings that must be set for the type of MAP being used.
The ignition system on a honda is very good. For almost all street cars, there is next to no reason to upgrade to external ignition boxes, external coils, or anything like that. 400hp and 9500 rpms are easily obtainable on the stock ignition system, provided it is in good working order.
Almost all ODB1 VTEC ecus use a 4-wire o2 sensor (except the VX, but that's VTEC-E anyway... it doesn't count). This allows for heater circuits to warm it up before the car warms up which provides a more accurate reading during start-up and a narrowband circuit to return an air/fuel reading back to the computer.
Wideband O2 sensors take this concept a step further. Hondata.com has a great detailed article about this topic: Wideband Tuning the beignning of the article dispalys the narrowband versus the wideband 02 sensors. As you can see, the narrow band circuit is pretty much useless for anything but stoich air/fuel ratios. This article explains what wideband and lambda o2 sensors are. Putting an air/fuel gauge on your car without a wideband o2 is simply a waste of money. The reading is garbage. More so, gauges like autometer, and so forth that plug into the stock o2 most likely won't work with a real wideband o2 sensor system. Why people buy them is beyond me.
I briefly mentioned the TPS earlier on. The importance of the TPS is that it tells the ecu if it is at WOT, or Wide Open Throttle or not. When we go to WOT and have a full load on the motor, the ecu goes to Open Loop. Open Loop is a state that the ecu doesn't read the sensors so much, especially the o2 sensor, and more so follows its pre-programmed map trace. Open loop also happens on first turn on when the car is cold. Closed loop is mostly used during part throttle and noraml driving. Again, Hondata.com has another great article on open vs closed loop circuits.
so bassically you have to crack open the case on the ECU and insert this chip and other smaller things and before you solder it in you have to program the fuel and ignition tables and whatever else is neccesary. but once its in how do you tune it? do you have to take it back out and re-write the chip? there is a gray area that no one on the forums or anything seem to cover
silentdaredevil said:
you need to solder in a socket- either a dip or a zif socket. dip is a press in socket, zif is a zero insertion force socket. what you see here is a zif socket, notice the lever that locks and unlocks the chip. you dont solder the chip in directly- that would make it impossible to reburn. you put a socket in place of the stock chip so you can change it out. if you're reading this, im not going to go into the actual soldering process, theres plenty of places to find out about that. just get your ecu socketed, places like moates.net will do it for 25 bucks plus supplies. this is what a socketed p06 ecu looks like with the chip installed in a zif socket.
it looks pretty much like a stock honda ecu, except for the blue socket in between the chip and the motherboard. when you flip the lever, viola, the chip comes out. (yea i know my carpet is dirty.)
take your chip to your handy-dandy chip burner (i got mine from moates.net for 85 bucks, you can spent anywhere from $50-250+ on a burner, but i find the moates to be very user friendly and it works great). load the chip into the socket on the burner. be sure to follow the instructions exactly on how to insert the chip, or you'll be burning something besides a .bin file!! (dont drink thebooze you see in the backround while doing this, or you'll have biggg problems lol)
fire up uberdata/crome/turboedit or whatever software you use. create your basemap, or if your tuning with a wideband or at a dyno, modify your current map (your .bin file) based on the results of your datalogging (the gray cable in the 1st pic, and your wideband readings). once thats done in your program and you've saved your map, use a burning program (i use flash and burn, it came with my burner) to load your .bin file onto the chip. be sure to clear the chip of the old program first, then load the new one on.
repeat until you have a solid a/f ratio line, you are making solid hp through the powerband, and you've successfully prevented detonation.
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mike, you whore. i wondered why my chip smelled like orange triple sec. b20 is running great on your chip.
io_303 said:
Piggy back or not, it still works. Apex SAFC/VFAC's have gone a long way in many different applications for a long time now. They shouldn't be considered crap just because they can't compare to a standalone. Same principal concept (tuning), but you're comparing apples to oranges.
Eran said:so ... yeah ... mike .... you're gonna burn chips for me, right buddy?
sure thing, send me a chip, tell me what your running, and i'll be happy to do it for you. ive already done a chip and a basemap for hatch, and his car runs perfect on it, ive messed with my map several times and have sorta gotten the hang of this stuff.
ill tell you what he it never fails every single time i need to know something and handlebars posts abot it i seem to pick it up
also does anyone still have the exe. file for uberdata because i can't seem to get it of the website it doesn't work
how do you know exactly what tables to change with out tuning?handlebarsfsr said:
http://uberdata.pgmfi.org/forum/attachments/Uberdata_1.70.zip
there is uberdata, you might need to sign up for the uberdata forums to get it.
there is uberdata, you might need to sign up for the uberdata forums to get it.
silentdaredevil said:
combination of experience, luck, and by watching your gauges, listening to the car, etc. it aint perfect, and it sure as hell isnt as good as a dyno or a wideband, but for a basemap it works. basemaps are inherently rich and conservatively timed, but thats their job, to get your motor safely boosted until you can get a real tune.