Max Torque Timing vs Spark Timing

[Higgs Boson]

with a stock engine, is the max torque timing the real mbt table or just theoretical?

let's say you run race gas on a stock engine, which will remove spark knock on a stock table, would matching the max torque table to the spark high table be too much timing, even without knock?

[gharris1100]

to my understanding it wont exceed the high octane table unless a multiplier table is bein used that adds timing. but im not 100% sure. I currently have a 2005 Silverado 5.3 that I literally copy and pasted the max torque timing in the both the low and high octane tables. (matching high and low octane tables done wonders for consistency at the strip) and have yet to log a knock retard on 87octane. and it runs really good. the values look high until you put them in the same format as the timing tables and compare them to another.( at least in my Silverado app). ive been very curious about the max torque timing for a while too but at first glance it seems WAY too high. It might be too much for towing or high gears, only one way to know for sure!

[Higgs Boson]

I am just asking if the Max Torque Table is a good substitute for finding MBT on a stock configuration. if you copy it over to High spark table on pump gas it's going to ping like crazy. so on race gas it won't ping but I am wondering if those values could still be beyond MBT.....

[SultanHassanMasTuning]

dyno will be the only way to find out, and some knock amps with race fueling

[Higgs Boson]

I'm aware of how to find MBT on a dyno. That's not my question, unfortunately. I want to know how the Max Torque Timing table is related to MBT on a stock engine, that's all I am asking. Let's keep it simple.

[h2.4]

As in the timing curve? If so I would assume that the timing curve for a completely stock engine would be really close. But once you sway away from stock components it will change as you know I'm sure. Or are you wondering about the spark advance in that table? I guess one could try using those spark numbers in the high and low maps and log.

[Higgs Boson]

On pump gas I add timing to the point of knock retard and then back it off a degree or two at all RPM/load combinations, smooth the map and that's my High Spark Map. I copy that to the Low map and subtract 3 to 5 degrees in all but the idle cells and that's my Low Map.

This is quite a bit lower than the Max Torque Timing Table, which makes sense because pump gas sucks and I expect to hit preignition limits before I get to Max Brake Torque (MBT).

So if I run race gas, let's say VP MS103, an unleaded oxygenated 103 Octane fuel, I can reach MBT before it knocks. However, without spending hrs on a dyno measuring single degree changes in timing, there is no real way to find MBT (especially at part throttle and cruise). You could find it at WOT at the race track.

So my question is, would setting the High Spark Table to match the Max Torque Timing table get the car to MBT without a dyno? Is setting spark to this table potentially past MBT?

The reason I ask is because I can get about 18 degrees out of the stock config on pump gas. Max Torque Timing is 25 degrees in the same cells. I can run 25 degrees on MS103 with no knock retard. I guess I just wonder if 25 is too high and or dangerous, even without any knock retard......

[jon6.0]

If you are at a track you could keep adding timing and stop when it stops getting faster.