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Okay here it is,May need to get some chips and a litter of coke b4 you start but here we go...The most extensive Honda Tuning Write up you will ever see/read . This is a culmination of data I have collected over 5 years of reading testing and tuning. I will cover everything so I can help you make an INFORMED decision when it comes to tuning your car, which is as important as changing your oil.ENJOY :D

All tuning should be done on a dyno. Dynos are able to measure power and torque vs air/fuel across the power band. Typically tuning pulls are made in either 3rd or 5th gear from 2000 rpm till redline. They measure the torque, power and air/fuel then adjust accordingly. For fuel-injected cars this can take many hours to get is almost perfect. Carburetored cars can take as little as 3 pulls for tuning. But carburetored are a lot simpler in design and don’t have computers to run them. DO NOT BUTT DYNO. IT DOESN'T WORK!!!

Tuning explained. Tuning is the process where your ECU monitors most inputs while you drive. It tries to create what is called stoich condition or Stoichiometric, which is 14.7:1 or 14.7 parts air to 1 part fuel coming out of your engine after combustion. This is of course and OEM and possibly an all-motor point. Turbo would be 13.2:1.

The Honda OEM ECU reads in 2 modes. They are open and closed loop. Open loop is where the ECU reads the inputs O2, MAP and so forth and tries to create a perfect mixture, even a little lean for better fuel mileage. Closed loop is where the ECU ignores the O2 and has a preset mixture in the ECU for power. Typically the ECU reads the MAP sensor then goes to the predetermined fuel and ignition values on the board. Some ECU’s can be chipped with different fuel and ignition values most typically for more power. Anytime the ECU goes into closed loop your gas mileage will suffer.

One thing to remember is that the Honda OEM ECU is VERY smart. It knows when you have changed something’s. It can learn and adapt. It makes long and short-term fuel corrections based on inputs. If you advance your distributor it will learn and retard the ignition to make up for that. If you change your fuel pressure and run it like that for too long it will kick back the amount of fuel it puts in (the injector pulse). The OEM ECU WANTS Stoich and will do anything to get it. The point of tuning is to get around the factory limitations of the ECU and provide more fuel and ignition for the amount of air you have added. The Factory ECU can compensate for up 25% more air.

NOTE: Honda ECU's Don't Read BOOST. Well more specifically 1988-2000. They can read 1.3 PSI which defined by Honda is Ram Air. The Sensors can read 11 PSI, but the ECU can not.
2001 and newer ECU's can read boost but the only people I know who can tune that is Hondata and Greddy.

There are many different methods and things you can use to tune your car. For most I/H/E Street people you can get away with Cam gears and fuel pressure regulator. This is easy and doesn’t require much tuning but you can still get better power and better fuel usage. When you have little things like these the Factory ECU is still able to keep up and make changes for the optimum setting for the car. Also with this setup you can still pass SMOG. (NOTE: Cam gears MUST be set at 0 degrees and Fuel pressure at stock with is 35-40 PSI, or you will not pass visual. There is no law saying you cannot have these things. As long as the stock numbers they should be at are represented then you’re fine.)

CHIPS. Not all ECU’s can be chipped. ODB-0 and ODB-1 can be chipped where ODB-2 cannot(Ive heard that there are possible ways to chip them but its very expensive and so Im kinda skeptical about it :rolleyes ). Don’t ask why just know that ODB-2 sucks for performance. There are conversion harnesses from ODB-2 to ODB-1 available from Skunk2 and Hondata. When chipping, it isn’t as easy as just plugging in a chip. Parts must be soldering in to help the chip run and have the factory ECU know that the chip is there.

Not all chips are the same. Many are made for fully built engines that rev to ungodly numbers (think 11,000 RPM B18C5 Type-R). Many different tuners have different approches and methods. so most of the time just picking a chip and plugging it in won't net you much HP, but it will suck your gas like a drunk at happy hour. And you have to think like a tuner. What will give this engine the most power AND reliablitiy. Power is nothing without reliability. If you car can't make it 1500 miles then why make said HP.
Then there are a variety of chips out there. Most popular are Mugen, Skunk2 and Spoon chips. Chips usually cost about $15 or $20. Please get them from someone trustworthy (I buy from this guy, Tell him Daniel sent you) and not from Ebay. Ebay chips are crap. They are Copies of copies with holes, sold by someone with a burner, looking for the quick buck.

For more about chipping if you want to do it yourself go here (

Now comes into play, things like VTEC Controllers and Fuel Controllers. They trick the ECU into seeing values that are off so you can get the power and values you want. There are 3 main ones I would stick with. The best are there units, Fields VTEC controller (has integrated fuel controller), APEX-I V-AFC (VTEV and Fuel controller), and Hondata. You can also run 2 of these together, most typically Hondata and one of the others.

VTEC is not something to change just because you think you can get more power. VTEC was designed to work a certain way. I agree changing it maybe 200 or 300 RPM sooner would help but that is best determained on a dyno. Honda did alot of R&D to find out where engagement is best. You are not supposed to feel VTEC engage. It needs to be a smooth engage that takes over when torque gives out. Butt dynos do NOT work.

Also fuel adjustment is not something to change by butt dynoing. The most you will see with fuel adjustment on a stock car is 5 hp which you can NOT feel not matter how much you think you can. Now some people will say that a - 4% across the board is a good adjustment. I say spend $85 and go get 3 dyno pulls with Air/fuel read out and find out. Then come back and ask if you don't want to spend the money to have that guy tune your shitz.

"Any thing that comes over the counter 'as a pre set chip that is not changeable' is a waste of money. Every motor is different and there is no way any company can make such a chip that will give gains to all motors. As far as changing the point of vtec engagement, go ahead if you want to make your car slower. The way vtec works requires certian variables to be met. Honda, after alot of R&D found that at the point it engages (stock) is the best point to have it at. The only reason you would/should ever want to change the point of vtec is if you change the internals (I.E. CTR pistons with Stage 2 cams and a big port job). And even then you will have to spend alot of time on the dyno to figure out the best point"

- Fields VTEC controller is the choice for most circuit racers. Their cars are already tuned and may need simple adjustments at the track. The Fields unit can change VTEC to any point from 2000-8000 RPM in 100-RPM increments. It can also make fuel adjustments from 1000-8000 at +/- 25% at 1000-RPM increments.
- Apex-I V-AFC is a lot more robust. It has the ability to change VTEC to any point from 2000-8000 RPM in 100-RPM increments. It can also make fuel adjustments from 1000-8000 at +/- 30% in 100-RPM increments and can do so in closed loop or open loop mode. Most tuning shops prefer this for street people as it can tune a lot better.
- Hondata. This has software behind the chip to help it. If you reading this then you can read more about Hondata. ( Just know that Hondata is probably the best there is for Honda ECU tuning. I like it far better then AEM EMS. And the price comparison makes it a lot better.

There are people who tune that don’t use Hondata. I am one of these people. I am still new to that scene but love learning and the do it yourself part. This is NOT for the people who don’t know shit, nor the people who can’t comprehend any of this or technically disinclined. You have to know your shit and be on you’re a game to do this.

There are many programs out there written by people who don’t want to pay for Hondata. The programs I use for chip tuning are CROME (OBD-1 with option for boost) and BRE (ODB-0 PR3). I also like to data log. I like to know how my car ran and what it did for the 20 minutes on the track. For this I use ECU Control. With these tools I can tune my car. But Like I said not for the technically disinclined.
-CROME is a Fuel and ignition points map editor. You can also change VTEC points, Idle, Rev limiter and some more stuff. You do need a chip burner to make chips.
-ECU Control does only data logging. Anything your ECU sees this program sees. This way you can tune it. You need to modify your ECU for this to work. A jumper must be removed and a serial board added to connect your ECU to your laptop.
-There are a number of people on here without VTEC and like it. For those of you who have 88-91 civics with PM6 ECU's I suggest Ghettodyne. I have heard good things about this.

For more info regarding this please go to . Sign up and you’ll be reading for the next 36 hours learning this crap or you’ll stop after 30 minutes and hire someone to tune your shitz.

"At the end of the day, all any chip or engine management system is doing is to provide the correct amount of fuel in relationship to the amount of air being consumed, and ignite it at the correct time, so provided that they are equally accurate, they should all come out with the same result, providing they are mapped to the individual engine by a competent tuner on an accurate dyno."
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