chip ideas

[JayLashua]

I have my chips at 18 degrees, maybe up to 20 depending on what im trying.

I'm experimenting with a home-made 16 position multichip right now (im too lazy to ad the 5th jumper to make it 32 positions.. besides, aint that overkill?

anyhow.

I have to add alot of fuel trim for rpm to supress knock, yet it reads rich either way. Stock chip fuel levels are horrible for knock on my car.

my valve seals leak, for sure. original turbo leaked on the compressor for about 2 months before i changed it.. it pufs huge oil smoke cloud when i start it, and then it goes away minutes later and the idle cleans up.

now this is what i figure from reading different sources:

burning oil leaves a artificial rich reading to the o2 sensor which it tries to take out fuel when it shouldnt. hence having to run high pe rpm trim..

now I never see any smoke while under boost.. which tells me the new turbo is still good.

I want to control, how much fuel can be removed from the o2 sensors readings..

its not just a bandaid cause im too cheap to get valve springs and seals, everyone knows switching o2 sensors are not entirely accurate. and I know better than to try and tune the car so the o2s read 760 when its probably closer to 650 and then blow a head gasket.. heh.

No I dont really know that much of what im talking about.. just opinions and (partially) educated guesses.

Either way, being able to burn 16 chips in 5 seconds on one EEProm device is sure as hell convenient. Looking for any suggestions possible.

I thought of limiting the blm low from 105 to 117 .. there are things such as oxygen sensor minimum correction value in units, and maximum correction value in units. This i am curious about. Can this be changed to limit how much fuel is added/removed ? how about more specificly, fuel removed? Noones blown a head gasket from running to much fuel AFAIK.. i'd rather run rich and not have the ecm take out too much fuel and blow up the engine. Then I can begin to -somewhat accurately- lower the fuel trim to a better performing level.. ie, not to the point where i get 10 mpg if im lucky..

alright that was a long post, but I'm looking for the opinions of you chip gurus, you know who you are. Thanks in advance.

 

[Eric Stage I]

Let me see if I understand... You want to prevent the program from removing too much fuel in the event that the O2 sensor is wrong. Is that correct?

I assume you are talking about WOT stuff here, so that means we're talking about BLM cell 15 and its ability to add and subtract fuel. Remember that cell 15 cannot learn under WOT conditions (when in PE mode). It learns under non-PE conditions, but still applies what it learned to the PE fuel calcs (in the factory prog).

Are you talking about doing a BLM lock? That way, PE fueling would not change no matter what cell 15 learned to.

PS. What are you using for the eeprom, a 1024kbit 32pin?

Regards,
Eric

 

[BoostKillsStres]

You might try searching both here and in the gnttype archives for a post from Carl Ijames as he put out about a 8 line BLM cell 15 lock patch that allows you to adjust the BLM lock value and trigger it via either TPS or MAF values. Works just fine. This way you also have complete control over your fuel pressure at WOT but you no longer have correction for large temperature changes so you have to watch that. When using direct scan you can see the patch in effect as it changes the INT value when it hits. I currently have mine set to 130.

You don't really want to correct your situation by forcing different min BLM values unless your completely sure of the problem you have as you'll be running rich at all conditions in that cell and any others that are low as the ecm will no longer be able to pul fuel out trying to attain 14.7:1 A/F.
HTH

 

[G McCall]

Not to start a post war.... but a rebuild is really to costly to reinvent the wheel here. Vendors like Yaklin and Casper have pretty much perfected the thumbwheel. If your thumbwheel is not working with your combo it may have been programed for another combination.
I have had thumbwheels by both of the above that worked perfectly. However when I ordered the chips I had to give my engine combination specs so the vendor could program it to match my combo. Well worth the money.

 

[JayLashua]

*I* made the chips that are in the thumbwheel. I made the thumbwheel .. its all my big own experiment, but im not steve y, and im not bruce, or jay carter. Ive been toying with chips for 3 months now, im trying to learn all I can about which settings i should play with, such and such.

with my o2 readings, knock readings, boost setting, timing values, trying to learn which works best together. i was hoping for someone like bruce or such to chime in.. anyhow

 

[Eric Stage I]

Jason,
Be more specific about your question. I thought Mark and I answered it. Maybe we misunderstood.

Eric

 

[bruce]

Originally posted by JayLashua

I'm experimenting with a home-made 16 position multichip right now (im too lazy to ad the 5th jumper to make it 32 positions.. besides, aint that overkill?

Dunno how you can do that.
I generally do one bin file at a time so that I have time to do proper notes.

The short simple and sweet answer is going to an open loop chip. Using a WB makes it really easy to do and get it right.

Even if you have to buy a high rent WB, they are cost effective, in the time, and gas you save. Never mind trying to figure out all the nuances.