HP Tuners Tuning Software

So if you can't avoid filling up with regular unleaded as opposed to super unleaded you would expect to see much more knock recorded and see more timing being pulled?

The LT1 was iron block with aluminum heads and featured a reverse flow cooling system. This meant that the heads got the coolest coolant allowing a more agressive timing curve. Wonder why GM did away with that on the LS motors?
 
AmericanThunder said:
So if you can't avoid filling up with regular unleaded as opposed to super unleaded you would expect to see much more knock recorded and see more timing being pulled?

The LT1 was iron block with aluminum heads and featured a reverse flow cooling system. This meant that the heads got the coolest coolant allowing a more agressive timing curve. Wonder why GM did away with that on the LS motors?
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More timing would normally be pulled with regular unleaded, but I would depends how far advanced you have made your timing, you could make your timing tables to never get knock with regular unleaded.
Usually the tuning method on LS1 tech is to advance the timing in little increments when doing WOT tuning, when you start to see knock then back off your timing by 4 degrees.

Not sure why the LS cooling is the way it is compared to LT1. The LT1 had the two center exhausts on each side close together, so I guess that would create a potential hot spot. Not sure how the new LT1 is arranged. I don't know all the differences between LS1 and LT1, I usually tell the difference by the exhaust manifold.
 
I recorded 4 logs last night of going to car club and coming back including the cruise. So been analysing all the data, and created a new file to try out. The spark timing still wanders when its going at a constant speed, and you can just feel it. Its fine when the car is under load which is interesting. Its like it doesn't know weather to accelerate or decelerate. I have re-enabled the idle spark table that I disabled yesterday. It must be interpolating between high octane and low octane spark tables. So i have made these values the same, only in the low load, low RPM region, just to prove something. If it still wanders then it must be trying to adjust idle timing which also alters timing, but it shouldn't be doing that when moving.

Its getting there, enjoyable tweaking things. Bulk of it working sweet, just final adjustments. This issue isn't new, been like that since i put the heads on about 10 years ago, never really bothered me, just setting myself little challenges.
 
Zapped in some adjustments this morning and took the T/A to work, took a little detour, nicely idles in school traffic. Feels good. Managed to get a constant speed at one part to try something, and still some minor bucking. I think the timing advance is too great at this engine speed and engine load. So the next thing is to alter the spark timings while driving, but that requires a passenger.
The software lets you bring up live controls where you can take so many timing degrees away, or add soo many. So my plan is to get the engine speed correct and engine load, and get the passenger to press the button with controls of how much timing. Not really possibly to safely do on my own, and cant leave it on that setting as it will effect all spark timing everywhere and I only want to tinker in that tiny area of the map. The other option is to guess and reflash, if worse, guess and reflash and try again. Nice to try in real life with a passenger with 1 degree increments/decrements to get a setting that feels good.
 
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