First Data Upload and New to the Forum

[EagleMark]

Async fueling is the devil and almost every V6 in the 7747 era ECM is this way. It really sucks for good idle in these Land Cruiser and Jeep I6 long runner intake designs. I've never ever not once been happy with a perfect Async bin tune!

Just start with a ASDU V8 Auto bin and change it to six cylinder and tune!

[HvyJet]

Async fueling is the devil and almost every V6 in the 7747 era ECM is this way. It really sucks for good idle in these Land Cruiser and Jeep I6 long runner intake designs. I've never ever not once been happy with a perfect Async bin tune!

Just start with a ASDU V8 Auto bin and change it to six cylinder and tune!

My other Landy idles GREAT with this bin......the only differences in the two vehicle setups are the cam and the exhaust size. Beside that every part is identical down to the air cleaner.

I can watch the data while the heated O2 sensors heats up and when it reaches the closed loop value the INT starts to decline along with the BLM s and it runs Rich....until closed loop it runs steady and a 128 BLM...I know its the PROM then in closed loop its the sensors.

[1project2many]

the only differences in the two vehicle setups are the cam

Kind of like saying "both the trucks are the same, the only difference is one has 44" tires." A small difference in name, but a large difference in practice. The cam affects airflow and therefore vacuum. The computer measures vacuum to determine how much fuel to deliver. Different vacuum readings equal different fuel delivery.

I have another identical setup on another 1978 FJ40 Land Cruiser [Bob Tail] I did around 6 years ago and it runs GREAT!

Ahhh... but not really identical. Sounds like you might need to make some changes to your calibration.

[EagleMark]

Usually a cam change from stock lowers vacuum at idle. For the Fueling VE table it means less fuel at idle and because of more cam... more fuel mid and upper RPM. There's also a lot that can be done to spark curve.

Open loop will usually run 128 BLM until CL feedback, problem with yours is it is maxed out rich = taking away fuel. 108 is max.

Bottom line is the cam change is going to need a chip change to run correctly.

[HvyJet]

Usually a cam change from stock lowers vacuum at idle. For the Fueling VE table it means less fuel at idle and because of more cam... more fuel mid and upper RPM. There's also a lot that can be done to spark curve.

Open loop will usually run 128 BLM until CL feedback, problem with yours is it is maxed out rich = taking away fuel. 108 is max.

Bottom line is the cam change is going to need a chip change to run correctly.

I kinda figured that I would need to thats how I ended up here!....based on looking at the data what should be changed first?