Best combo to lean out your engine

[sjrobinson]

I guess Im back in since I have time to put my system back in my car. Its healthier and I have a bit more knowledge and some good ideas.

My question is, whats the best combination of sensory 'trickers' have you found to work.

My car is a 97 Accord Ex with a 2.2L Vtec. So its a MAP sensor engine but just at the point where obd2 came in. Not too difficult to trick. I have an EFIE. Originally my combo was a pot on the map sensor and EFIE on the o2 sensors.

Would a pot on the IAT or ECT sensors work better?

My idea is to trick the ECU in a way that is most accurate to what your doing. So to lean out the engine perhaps tricking the IAT since it adjusts to whether or not the air allows for more ideal combustion (and knocking). HHO would essentially be mimicking cooler air right?

[valk01]

Id think you would want to add voltage to iat as it would retard ignition timing? From what ive read so far seems like adding hho would create perma knock cause it burns so much faster than the fuel/air?

Might also look into a piggyback fuel system. Being honda you have maby choices that will allow you to tune the engine however you wish.

[ultra_efficient]

leaning your engine can have adverse effects. first before tuning i will install a EGT gauge to see what my engine's normal EGT values are and what safe ect..... then i install a AFC in this case im using a SAFC1, then i tune a little lean at first to see how the EGT reacts to it then a tune a little leaner until i get to the edge of the safe zone. on the other hand lean tuning is very good when it comes to deceleration because it helps to cool the EGT. in my setup i also have a vacuum guage to monitor a vacuum switch that i installed and ofcourse you have to have a air/fuel ratio guage to see how lean your tune is at what RPM at what TP(throttle position) etc....

http://www.youtube.com/watch?v=ZHdV5SBysdk

[sjrobinson]

I am aware of the leaning process. Ill take a look at the video.

I found an inexpensive exhaust temp gauge that I plan on using.

But what combo of devices do you find work best for tricking the ECU? I always thought an EFIE and Map sensor pot are sufficient but never got to test too much.

[maxgtr]

I am aware of the leaning process. Ill take a look at the video.

I found an inexpensive exhaust temp gauge that I plan on using.

But what combo of devices do you find work best for tricking the ECU? I always thought an EFIE and Map sensor pot are sufficient but never got to test too much.

I honestly think a wideband o2 sensor setup and an engine hack like safc or vafc , you can subtract fuel more precisely and actually know what afr you are at. More expensive options are emanage, emanage ultimate, and aem fic. With these and a laptop you can access afr, injection, and timing maps to make adjustments but you need a wideband o2 setup to know your afrs.

[valk01]

if you want full tunability, you probably want to get the wideband, egt ect and a stand alone engine managment system like a haltech sprint 500 or similar. fic will work but piggy back systems are always fighting the onboard computer.
I run a Split second afc in my boosted protege and the computer will always win unless the car goes into boost. the afc then clamps the o2 and maf voltages and adjusts the fuel maps as the stock ecu goes into map mode.

i still have to unhook the battery from time to time as it does learn around the afc given enough kms.

stand alone and a dyno tune session seems the way i think. most $1000 stand alones will have data logging function to record the afr's for a given rpm range. of course, it does require rewiring the better part of your car. definitely not advisable for a newer car. 2000ish vintage would be just perfect.