How to guard against lean

[kevinvinv]

So I am new.

94 Chevy 454 TBI

I want to be sure as I mess with this tuning that I don't get too lean and burn a valve or something like that.

What is the best way to watch for that?

Is it satisfactory to monitor the Block Learn (or whatever it is called in 1994)? Am I way off base on this?

Thanks!!

[steveo]

if you have a narrowband o2 sensor hooked up and the engine is warmed up, then it wont go lean EXCEPT at wide open throttle, cold start, and fast throttle transitions.

so while you're tuning, the idea is to let it warm up a bit before you drive it, and not floor it, be gentle. get it 'in the ballpark' as quickly as you can using injector constant (bpw) stuff then start to fine tune it and run it a bit harder.

past that, yeah, block learn mode will give you a good idea of where you are

i'd prefer to actually check the BLMs, then push it into 'rich' territory if i find it lean, then fine tune it from there, which is much safer.

being a bit lean wont torch anything, dont worry too much.

[kevinvinv]

if you have a narrowband o2 sensor hooked up and the engine is warmed up, then it wont go lean EXCEPT at wide open throttle, cold start, and fast throttle transitions.

so while you're tuning, the idea is to let it warm up a bit before you drive it, and not floor it, be gentle. get it 'in the ballpark' as quickly as you can using injector constant (bpw) stuff then start to fine tune it and run it a bit harder.

past that, yeah, block learn mode will give you a good idea of where you are

i'd prefer to actually check the BLMs, then push it into 'rich' territory if i find it lean, then fine tune it from there, which is much safer.

being a bit lean wont torch anything, dont worry too much.

Thanks! And is a high or low block learn an indication of Lean? I can't seem to remember and I guess I am too lazy right now to search. I won't hold it against you if you don't answer :)

[kevinvinv]

if you have a narrowband o2 sensor hooked up and the engine is warmed up, then it wont go lean EXCEPT at wide open throttle, cold start, and fast throttle transitions.

so while you're tuning, the idea is to let it warm up a bit before you drive it, and not floor it, be gentle. get it 'in the ballpark' as quickly as you can using injector constant (bpw) stuff then start to fine tune it and run it a bit harder.

past that, yeah, block learn mode will give you a good idea of where you are

i'd prefer to actually check the BLMs, then push it into 'rich' territory if i find it lean, then fine tune it from there, which is much safer.

being a bit lean wont torch anything, dont worry too much.

Hey Steveo, I was looking at your sig and then went to look at your XDF on your site…. You might be a guy that I can ask this question to...

What I want to do is take all of the engine related tables from a 454 chip and stick them in a small block chevy chip-- leaving all the transmission stuff and whatever else the same. Why? B/C I put a 454 in my half ton truck but kept the 4L60 trans.

People here have been saying the best thing to do is open two instances of TunerPro and cut/paste the tables between the two… BUT… I can write c -- and I thought in theory a person could parse out the XDF file and just binary copy the engine bits from the 454 bin into the same slots of the 350 bin… you following me?

It sounds easy assuming the XDF format is understandable and there are not too many nuances etc… do you have an opinion on this?

Thanks man!!

[steveo]

no; that'd be a rough way to do it.

you're talking about copying tables from one mask to another, right? if it was to the same mask you'd just use the entire bin.

the tables may even be different sizes. this stuff has to be done manually to be done properly.

if you're talking about taking part of the code (but not all) from different masks, there's no way

[steveo]

Thanks! And is a high or low block learn an indication of Lean? I can't seem to remember and I guess I am too lazy right now to search. I won't hold it against you if you don't answer :)

high (over 128) means fuel was added (it was lean)

[kevinvinv]

no; that'd be a rough way to do it.

you're talking about copying tables from one mask to another, right? if it was to the same mask you'd just use the entire bin.

the tables may even be different sizes. this stuff has to be done manually to be done properly.

if you're talking about taking part of the code (but not all) from different masks, there's no way

Yeah- talking about copying tables from a $0E mask into a $0D mask. OK- I guess I'll try to do it manually then… sounds painful.

[1project2many]

People here have been saying the best thing to do is open two instances of TunerPro and cut/paste the tables between the two… BUT… I can write c -- and I thought in theory a person could parse out the XDF file and just binary copy the engine bits from the 454 bin into the same slots of the 350 bin… you following me?

I like the idea. I'm the kind of person that falls asleep while trying to copy tables. I get bored switching back and forth over and over and inadvertently end up omitting or duplicating values. I think a utility would be a great tool. The binary is just values... there's no text based table definition included. You'll have to define all the locations to copy from SOF. A small utility that uses a control file could copy each location as defined until keyword "end" or EOF. You could expand the file with a "from" and "to" definitions to handle mismatched masks. With a common core of control files it could be handy for all, but you'd invest much more time and effort than just copying tables manually.