New to tuning

[3500rsz24]

I just picked up a ostrich 2.0 for my 3400/3500 cav. I am still waiting for my aldl cable to arrive i was wondering if anyone has any tips of things to change for the 3.5l. I can only find a stock 3.1 bin. i have been browsing the tuning section and have the multec 2 injectors running decent in the car. I have changed things for bigger injectors but theres too many other things to know what to change.Any help will be appreciated

[3500rsz24]

ok well i have been searching i found nasty1's 3500 spark and ve talbles but that does not help when other stuff is still running the 3.1 tune and also im unaware for exactly what to change in the idle ve table do i change them all at the same time same goes for main ve and ve adder tables. ? Its a 89 cav 3500/3500 but it has the bfuz memcal.

[SappySE107]

the idle table is not used by default in the nast1 (is it nasty1, i don't know), so just tune the 400-2000 RPM table for idle. You can start by using the BLM history table, average running. The mid table needs the math fixed to actually multiply the percentage against the stock value.

Have you changed the BPC vs EGR to match the multec 2 injectors yet?

[3500rsz24]

I have played with it a little i saw superdave posted it should be at 150 for 22.5# inj which i believe thats what the multec 2's are. Do i change them all to 150 or how do i adjust the other ones.

[SappySE107]

I think I use 130, but I do a lot of other stuff too so anywhere in there is probably as good a place as any to start with. If you turn the EGR off (EGR vs Coolant Temp), then only the 0% EGR needs to be changed. Otherwise you have to do the math, which I have not memorized.

[3500rsz24]

ok the bpc is at 150 and it idles around 14.5 to 15.3ish for air/fuel. The car still has the bog when i hit the gas like it doesn't burn the gas properly. When the car is cold it runs amazing once it warms up it does not burn the fuel the same any ideas on what to change to help this. The one thing that might take part is half the tune is still a 3.1 tune and the only thing is changed is the bpc for the bigger injectors which probably doesn't help on stock tune.

[Schmieder]

ok the bpc is at 150 and it idles around 14.5 to 15.3ish for air/fuel. The car still has the bog when i hit the gas like it doesn't burn the gas properly. When the car is cold it runs amazing once it warms up it does not burn the fuel the same any ideas on what to change to help this. The one thing that might take part is half the tune is still a 3.1 tune and the only thing is changed is the bpc for the bigger injectors which probably doesn't help on stock tune.

Could be your Acceleration Enrichment causing that bog at tip in. Especially if you turn off the AE, it will bog like that. What happens is the sudden loss of vacuum causes the fuel vapors to condense and "rain fuel" in the intake runners. For that brief moment the aircharge is lean, then the heat will evaporate the fuel that "rained" onto the runner walls and re-enrich the aircharge. The AE modifier aids in balancing this. It is a hit or miss kinda thing unless you want to get into some SERIOUS math and several moderately long logging runs.

When the car is cool it runs richer, meaning the aircharge will keep a more combustable ratio when the vacuum is lost at tip in.

Same thing with decel enleanment but is opposite concept. The introduction of vacuum causes a flash evap of liquid fuel on the runner walls, causing the aircharge to richen up. Decel enleanment tries to balance this.

Though, other issues can cause a bog at tip in and messing with AE is really the last thing you do tuning. Did you reset the fuel trims since installing new injectors? Disconnect battery?

Car runs better when cool due to open loop fueling, then closed loop changes the fueling IF the PCM detects a rich or lean condition. If you have an exhaust leak ahead of the o2 sensor, it will cause your car to run too rich in closed loop but will not effect fueling in open loop.

[SappySE107]

Its not that it "rains fuel", so much as it just doesn't have the fuel shot needed for the quick increase in airflow. AE is like an accelerator pump on a carb. From the sound of it, this is not where we need to be for tuning. The main VE table is no where close to right if this is a stock file with just the BPC changed. You need to get as many steady state readings as possible, such as 60kpa 2000 RPM, or wherever your cruise is. The more points on the table that you can hit and stay at, the better. Any change in TPS and rpm/kpa will change the transients like AE fueling and should be be corrected for in the main tables. You will undoubtedly use some values between the steady state values just to get the table to not be full of spikes and pits.

For now, you will have to get the BLM in a decent range with the INT not going min/max. We need to get the fueling closer before the BLM is locked and the fine tuning with INT begins. That is the fastest way. For now you have to add BLM and INT per RPM/MAP point and divide by 2 to get the fueling at that point.

[3500rsz24]

So what table would i change there's a few AE table . How would i reset the fuel trims, I don't think i unhooked my battery since i updated my most recent tune and no exaust leaks before o2. While i was driving under wot it would be around 14.7 - 15 but has the bog while cruising and hitting the gas and also when decelerating it goes up to 17 and just shows - - because its maxed out.

[3500rsz24]

In the flags menu theres a option to keep the car in open loop is there anything this will affect if i always ran it in open loop?

[TGP37]

Its not that it "rains fuel", so much as it just doesn't have the fuel shot needed for the quick increase in airflow. AE is like an accelerator pump on a carb.

I learned something new, sort of...lol

In the flags menu theres a option to keep the car in open loop is there anything this will affect if i always ran it in open loop?

I run open loop very often. You will not have certain features and the protection the O2 offers. The O2 helps keep the system stoich at low rpms. It compensates for engine wear over the years which would normally skew the AFR rich or lean.

So what table would i change there's a few AE table . How would i reset the fuel trims, I don't think i unhooked my battery since i updated my most recent tune and no exaust leaks before o2. While i was driving under wot it would be around 14.7 - 15 but has the bog while cruising and hitting the gas and also when decelerating it goes up to 17 and just shows - - because its maxed out.

I adjust "AE vs. TPS Max Delta" to tune specific throttle % tip-ins and "Decay Profile" to dictate how the extra fuel shot is given over time. It is very tricky tuning AE, and is best left when everything else is tuned.

Going lean while decel is normal, but hitting 14.7-15.0 AFR while WOT isn't good at all. Reset your fuel trims and check your TPS (throttle position sensor). I heard the TPS on my engine (3100 L82) is fragile to moisture, water. Yours may be the same or similar, more then likely. A bad spot in the TPS can cause a blip in fueling and may even prevent Power Enrichment from kicking in.

You want mid 12's for WOT which is optimal for power if you are not boosting. Otherwise go low 11's for low boost and high 10's for moderate + boost.

[3500rsz24]

how Would i reset the fuel trims?

[TGP37]

how Would i reset the fuel trims?

Unplug your battery overnight.

[SappySE107]

it takes 2 seconds to reset fuel trims. Unplug ECM fuse, plug fuse in, done. Same with battery if you don't mind losing your radio settings. Its instant with battery power loss to the ECM as it has no battery backup.

[3500rsz24]

Ok my cable finally came and i just datalogged my 5 spd 3400/3500 cav for the first time. Here it is test.csv