DaytonaBlues

I recently bought a Launch scantool and was reading some data off it. Im trying to figure out if the kid before me used a Diablo handheld programmer. it sure looks that way or at least i might have a 160 tstat. The car at idle never gets over 200 degrees, fan comes on at about 195 degrees and on the main roads, 5th gear, 1500 rpm, temp on the scantool shows not even 160 degrees. it hovers at almost 150 degrees, and takes a LONG time to even hit 185. timing shows 30 degrees at idle and hits 42-45 degrees, ST fuel trims are ok, between plus 15% and minus 10% i think. gotta check on that not that the STFT matters.
from my super low temps and way early fan kick on temp at 195 degrees, im assuming someone put a tune on this thing i was just curious if there is any other ways i can tell i may have had a tune done by looking at scan tool data stream.
any ideas on what i can look at or what my data should be for a stock M6 Z28 engine, minus a lid, loudmouth usual bolt ons?

sreve

iTrader: (3)

Best way without tuning software is to look up the CVNs (calibration verification #s)
These are check sums, GM lists the stock CVNs to compare. You can not alter the tune with out these changing. They may or may not be labeled on your scan tool but will be in this order (see pic). The look up can be found here.....

http://tis2web.service.gm.com/tis2web

RPM WS6

iTrader: (3)

If the fan is cutting on at 195°, then at least part of the tune has definitely been modified. Stock fan settings are as follows:

Low speed on/off: 227°/218°F
High speed on/off: 235°/228°F

wooddaniel

iTrader: (28)

It's probably tuned and has a 160 degree tstat. If it didnt the car would get hotter idling. If it had a 160 degree stat and no tune it would still get hot just sitting because the fans dont turn on till hot.

DaytonaBlues

Thanks for all, the responses guys I really appreciate it. As far as scan numbers etc my scan tool is a Launch Creader V I got for cheap and I use it simply to see how my o2 sensors are doing, what my short term fuel trim %`s are and watching coolant temp. Those cvn numbers are pretty complicated but thanks for teaching me about them I'll do some more research. I think the coolant temps I'm getting and the fact my single low speed fan comes at about 195 ish degrees is kinda a indication I did have a predator programmer used at one point since when I bought the car the kid said he would include it.
That being said, my concern is the car actually runs too cold, after 15-20 minutes normal driving I barely see my scan tool indicate coolant temp past 150 degrees. What?!?!?!?!
Its nuts. It is about 35-40 degrees out I know but shouldn't the car be running at least 170-180 with a 160 stat? Should I be worried?
Once I get in traffic the car if EVER gets over 190. Mostly the warmest it gets driving around is 180. If I let it sit and idle, its hard to get it to go over 195. I've never seen 200 degree water temp n the scan tool. My gauge on the car shows 200 degrees which actually turns out to be around 170. The motor runs great and I run 1040 high mileage synthetic Mobil One with some valve train noise cause like an idiot I switched from the Castrol Syntec.
Secondly, is there any other parameters with my basic data stream coming from my scan
tool I can look at to check what kind of tune? Can looking at my timing data tell me anything?
Thanks again fellas

sreve

iTrader: (3)

Well that makes it easy plug the Predator in and you will find your answer.
They do a decent tune on a stock car. As said car has some mods to the tune.
A 160* stat is counter productive I do not see how thermal efficiency would be enough to make good power. I run a 180* stat it keeps coolant temps just above 200* but I rarely drive it in cold weather.

RPM WS6

iTrader: (3)

It's possibile that the t-stat is stuck open. This would allow coolant temps to get pretty cool while cruising at steady speed in 35-40° outside temps.

For a '99, I believe the max WOT timing would have been 27-28° or so in the stock tune file. You will see numbers much higher than that while at cruise under various conditions, but I don't recall ever seeing anything higher than that number at WOT on a stock tune for a '98-'00 car. Of course that number will be effected by any knock retard that might be present, so you'd also have to be able to see KR to know if the WOT timing that you're actually attaining is the same as what's been programmed.

DaytonaBlues

Rpm and sreve thanks for the help. I'll do a WOT run on the scan tool and graph the timing and see what it gets to. At idle the timing is Stable around 38-40 degrees. I've seen 45 degrees on occasion on the scan tool. Is KR knock retard? I got a real basic scan tool like I said so I don't know how I'll get any info from the knock sensors. The car pulls really hard all the way to the rev limiter or fuel cutoff 6500 from or so, and it never burped or anything. Car has a sealed under car ram air which I think is the fast toys kit or the slip flow pack simply because my SLP lid is completely sealed with gaskets. My MAF sensor has been descreees to if that helps which I have heard screws up the MAF tables on some cars. MyIAT temps are really low because of this, in 35 degree weather I always see never less than 50 degree IAT on the scan tool.
As for thermostat stuck open I never thought of that but the car warms up eventually and I drive really carefully slow most of the time. I baby the car so I'm usually in 5th gear or higher never cruise above 2000 from anytime, hence my very low coolant temps. I'll have to check out my thermostat. When the car does warm up, its near perfect 185 in winter temps, once I hit the open road it gets down back to 155-160 however. The water pump has been replaced recently, so I'm assuming the tstat was replaced. I'll check it out thanks sreve. Rpm thanks too. It sucks I'm the only guy within 100 miles with a Ls1 anything so its hard to find people who know their stuff, I have yet to head to Slowhawks though.
Any other ideas I can do would much appreciated

RPM WS6

iTrader: (3)

Glad to help.

Yes, KR = Knock Retard. If your scan tool doesn't show this value then there isn't really any other way of reading it.

The stock rev limiter is 6200rpm, so if you're revving to 6500 then that's another thing that has been changed in the tune.

wooddaniel

iTrader: (28)

This. Im sure it's tuned revving that high.