more air = higher compression?

[jchev502]

Does anyone know that if you Change your cylinder volume to a higher setting but havent changed the bore of the engine if it will give you a higher compression without hurting anything. That and any ideas on what is the max spark advance able at an idle and from and idle to WOT. (i.e. trying to make more low end torque)

[thunder550]

Compression ratio is determined by the mechanical parts inside the engine, not in the tune. If you mess with the cylinder volume in the tuning file you will throw off all of the fueling calculations that the PCM does.

[BlackGMC]

CHanging that setting will automatically change your VE table, thus throwing your tune off!

[TAQuickness]

there is not a simple answer for the max spark question. The max value the tune tool will let you enter for an LS1 PCM is -45 to 60. Max spark that your engine will allow before detonating, or worse, can only be determined with a dyno or some means of measuring engine torque.