hodge9386

Just curious to what your timing strategy is? I have been doing my own tuning for a few years now and I am by no means a expert and am always trying to learn new things. I have done a lot of reading on timing and it seems to be some huge secret within the tuning world. It is pretty common knowledge that a ls1 style engine likes 24-28 degrees of timing at wot but without having a dyno how are you supposed to know if it likes 24 or 28 degrees? My engine seems to like around 25 degrees so thats what I run it at and it runs very well but who knows. Also what is the best way to bring in the timing? Do you start low and bring it in up top or do you give it more timing down low bring it down up top? I have been starting low and ramping it up to my desired timing around 3000 rpm. I have looked at several tunes in the repository and this seems to be how most people do it and my car seems to run well doing it that way but if there is a better way please teach me.

hodge9386

I attached a copy of my tune so you can tell me what you think.

hodge9386

I also understand that every car is different and will like different timing I am more interested in the theory of how to get the most low end tq and high end power.

Here is the mods to my car

99 vette
stock ls1 160k
sns stage 3 tq max cam 235/243 | .630"/.610" | LSA111+2
hand ported 243 heads. I did not go crazy with these just smoothed out the cast, removed the rocker bump and shaped the valve guide bosses. I did open up the exhaust port a little but on the long side of the port. No mill.
ported ls2 intake. I just smoothed out where the 2 halves meet, I did not open the port up any.
ported ls2 tb
85mm truck maf
hurricane intake system
top speed long tube headers and x pipe
borla stinger exhaust

tblu92

The key to determining what the best timing for your engine combination revolves around many variables
1st Even though you may ask for or command 28* doe s not necessarily mean that is what you are ending up with----The only true way to know your "actual timing" is to data log your timing tables---You may ask for 28 but only be getting 24
You need to find out via data logging if indeed you are getting the timing you are asking for
The variables are IAT temps which will subtract timing when too high---OR coolant temp which again will subtract timing when too high
--Data logging will show if IAT or ECT temps are removing timing--
2nd you must identify whether he timing deducts (commanded vs actual)is indeed real knock or false knock-----Real knock is easy to identify as you can hear the engine ping
FALSE KNOCK is trickier-----You will get some timing deductions so the commanded does not match the actual timing BUT you will hear NO detonation or pinging----This is qvery common with modded engines especially those with LT hearders--Reason being the headers have such thinner walls than the stock cast exhaust that the knock sensors will mistakenly interpret these new noises as KNOCK----On every car I tune with LT headers i always have to "desensitize" the knock sensors to eliminate this false knock
The 1st step you need to do is data log your timing tables and that will tell if you are having a timing mismatch---commanded does not match actual timing--
PS My 2002 LS1 with LS6 heads and mild .225 @ .050 cam with LT headers ran best with a WOT timing above 3500 RPM's with about 26 * ACTUAL TIMING

schpenxel

File is tuner locked.

hodge9386

yea sorry I didnt know the default was to lock the tune. I understand the true timing deal, im not pulling any timing from any of those things. attached is a unlocked tune that i added some timing to down low and a log i did before i added the timing. I really think my ls2 intake is restricting the car. I am only getting about .72 cylinder air mass at wot. Also attached my layout

hodge9386

sorry this one should be unlocked this time haha

schpenxel

The default isn't to lock the tune.

schpenxel

That one is setup for a remote tuning network, so no one else can open it.

RonSSNova

C'mon dude. Tell him how to set up 3.0 so it doesn't do that.

schpenxel

Hit the clear master/slave button

hodge9386

Jesus frekin christ, try this one lol

Blow Torch

These guys know a lot more than I do, but I would just run the 28* on out through 6800rpm and data log and look for KR. If the log shows it is hitting 28 and it doesn't have KR, let it roll. My wife's car has a similar size cam but with a higher LSA and 10.9CR and it handles 28* with no spark knock. (although we've never run it hard on one of these 100* days like we're having now.
And your low octane table should be the same as your high octane table.

romandian

i wonder about this also. i have seen tunes, where the spark rises with rpm to the redline.

btw, did you know a holden commodore ls1 will have 16°/8° wot spark? why is that and how do these engines run? why dont they overheat in the australian weather?