Please Review This Tune.. 99 >>> 02

[tatasta]

Hello,

I have been working on this tune to migrate my calibrations from my original 1999 operating system to the newer 2002.

Future plans are to go to a VE tune and later to COS5.

Basically, I would just like to know if there are any big, glaring mistakes that I have made. I have not ran this yet so no logs but if the tune looks safe, I will load it and log some info.

I run a 100 hp wet shot so please keep that in mind while reviewing the tune.

Thank you

[joecar]

Looks good to me... when you full flash that in, your car should run as before.

[tatasta]

Thanks joe,

I made a rookie mistake, though. Went down to my car to load the OS. Bad time to realize that I need a commercial license and uhh... don't have one. lol Guess I'll be ordering one.

Thanks again

[Rontune]

My experience with 99 to 02 operating system conversion was big time knock sensor/KR problems. Car ran fine, was functional, but couldn’t sort out KR problems - went back to 99 operating system. Anyone else have this problem…if so, did you solve it.

[jetblast]

your timing table looks too advanced for that size shot, this tune was with a nano sys. and ran it at the track just yesterday. see comments section for more info. my wet shot kicks in at 4k rpm shuts off at 6.4krpm with a 6.5kfuel shit off. and i have 42lbs injectors with a walboro 340 . on a 100shot i usually see about 18degs when the shot kicks in

[joecar]

jetblast, I agree with what you're saying...

Robert is going to upgrade from 12212156 to 02020005 (COS5) where he can set the nitrous VE and spark modifier tables (triggered from PCM input pin which he will wire from nitrous solenoid/relay).

[jetblast]

oh!! ok, just thought that he was going to spray with that tune before the cos5 is enabled. the timing is kinda high anyways for n/a. i would not be comfortable if the eng. is not seing 18degs on a 100w shot especially with a cam with tighter lsa and perhaps a good efficient cnc cylinder head. that tune i posted gives me 20degs on the spray. i run 18 for the 100w and about 16 on the 150w and so on. i run 22 n/a.

[tatasta]

your timing table looks too advanced for that size shot, this tune was with a nano sys. and ran it at the track just yesterday. see comments section for more info. my wet shot kicks in at 4k rpm shuts off at 6.4krpm with a 6.5kfuel shit off. and i have 42lbs injectors with a walboro 340 . on a 100shot i usually see about 18degs when the shot kicks in

Thank you for the info and for posting up your tune.

What is normally considered a safe/best amount of advance when running WOT and N/A?

When STS was doing my tuning, my advance was around 29* when WOT AND on the 100 shot. I ran that tune for over a year a through a couple of bottles. I was not able to log my data but would have a friend write down real time data off of my Predator and never did see any KR nor did I see any other real problems. I am certainly not saying that I didn't have any issues with my tune back then but car did run good. I bought my EFI Live primarily to get my TCC straightened up but now I seem to be getting deeper and deeper.

I am adjusting my high and low octane tables to dial in timing. What are the other parameters to focus on while dealing with advance?

Next subject on my agenda is trying to get actual AFR to match commanded. (any tips would be great)

I will try to attach a huge log from my first run using the tune I posted in this thread.

Thanks

[joecar]

I don't know/remember the exact rules of thumb (I did research it once), but they are something like this:
- reduce timing by 2° for every 50 hp of shot,
- set AFR as rich as 11.0-11.5,
- make sure your fuel pump(s) can deliver reliably,
- use spark plugs two steps colder,
- use 92 octane gas or higher,
- limit your rpm min/max window (spray at/above peak TQ, stop before rev limiter),
- don't spray if there is insufficient fuel or rpms.

The AFR and timing are important... even if you don't see knock, combustion chamber temperatures going sky high will damage the pistons (which are only aluminium alloy).

Some people get lucky.

[joecar]

29° for NA is on the high side for the LS1...

It has been found empirically in dyno sessions that even if 29° doesn't knock (the CC temps will be higher), there was negligible or no power increase by going from say 27° to 29°... so a safe practice is to run at the lower timing (CC temps will be lower and the ability to knock is reduced).