new tune for new compression ratio
Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 328
From: CA.
St. Jude Donor '13-'14-'15
Without seeing the tune and timing table it would be difficult to point fingers at the tuner--- Every tuner tunes differently----Some leave all the IAT and ECT timing deducts in place--with that style of tuning yes you could get away with 16 degrees of timing commanded as you still have the high temp IAT/ECT deducts in place
However most tuners will massage the IAT/ECT timing deducts so the eng is easier to have the actual timing equal the commanded timing---Beyond that the IAT deducts are most often false due to under hood heak soak where the IAT sensor will read 130* when it's only 80* ambient air temperature---
Final absolute timing is what the data logger shows on a WOT run---This is what you really need to view in order to know IF you may have too much timing in the engine
My experience is that boosted LS engines typically only run about 11-14* of final actual timing----( some N/A LS6 C5's run best with only 17-19* of timing at WOT !!!
So a boosted engine with 8 PSI boost should heave an "actual final timing "below 14*
Doesn't matter what the commanded timing is--- the only way to see the ACTUAL timing is by using a data logger------
I would also like to see the tune---In order to see if the tuner deleted the timing deducts or nor----
However most tuners will massage the IAT/ECT timing deducts so the eng is easier to have the actual timing equal the commanded timing---Beyond that the IAT deducts are most often false due to under hood heak soak where the IAT sensor will read 130* when it's only 80* ambient air temperature---
Final absolute timing is what the data logger shows on a WOT run---This is what you really need to view in order to know IF you may have too much timing in the engine
My experience is that boosted LS engines typically only run about 11-14* of final actual timing----( some N/A LS6 C5's run best with only 17-19* of timing at WOT !!!
So a boosted engine with 8 PSI boost should heave an "actual final timing "below 14*
Doesn't matter what the commanded timing is--- the only way to see the ACTUAL timing is by using a data logger------
I would also like to see the tune---In order to see if the tuner deleted the timing deducts or nor----
Race Director
Joined: Dec 2013
Posts: 12,502
Likes: 3,629
With boost comes heat (from the boost pressure itself).
Heat will cause detonation, so tuner will run the AFR on the richer side to combat both the heat and the detonation when a meth kit is not in use.
The glitch, you run too rich, and now you are just flushing the oil on the cylinder walls off, and now chance a piston seize from the metal on metal instead.
So the 50% water in the meth will help deal with the increase boost heat before it has a chance to over heat the motor itself (and not flush the oil layer off the cylinder walls), and the other 50% meth in the mix is your octane safety factor so you are always keeping the octane rating over what the tune is trying to use for advance timing instead.
If you are using the Meth kit, such as in the case of straight meth, to the excel how far you can push the timing itself, then mistake in itself, and you should have just gone Nitro-meth to begin with instead.
Simply, meth kit is used as your safety margin for street use, and not to just turn the car into a true E-85 runner instead.
Heat will cause detonation, so tuner will run the AFR on the richer side to combat both the heat and the detonation when a meth kit is not in use.
The glitch, you run too rich, and now you are just flushing the oil on the cylinder walls off, and now chance a piston seize from the metal on metal instead.
So the 50% water in the meth will help deal with the increase boost heat before it has a chance to over heat the motor itself (and not flush the oil layer off the cylinder walls), and the other 50% meth in the mix is your octane safety factor so you are always keeping the octane rating over what the tune is trying to use for advance timing instead.
If you are using the Meth kit, such as in the case of straight meth, to the excel how far you can push the timing itself, then mistake in itself, and you should have just gone Nitro-meth to begin with instead.
Simply, meth kit is used as your safety margin for street use, and not to just turn the car into a true E-85 runner instead.
