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16168625
No. Not at all. Will read up on it.
Thanks.
Gearing will change the load on the engine thus the amount of throttle you require to run at a steady speed. 3.08 gear will take more throttle than say a 3.73 to run the same speed. The GM Memcals for the electronic transmission trucks are specific to a factory gear ratio. 3.08, 3.42 and 3.73 all being different in the 1/2 ton models with the 4L60E. The DRACs or VSSBs are also specific to the tire size and rear end gearing although they can be modified with a DIP switch or switches (single vs dual jumper setup) to correct the VSS pulse for various tire sizes and gearing. Also the 4.3L and 5.0L generally have a bit more aggressive shift pattern than the 5.7L because they make less torque. The 4.3L and 5.0L will hold the gears longer accelerating and downshift more easily under load. I used the factory 5.0L L30 tune as a starting point when I put a L30 in my 99 Tahoe so that the calibration was as close to factory as possible using the 5.0L Vortec. Even in a heavy Tahoe with 3.42s on 33s the little L30 5.0L was no slouch.
What does this mean if I still have my original memcal for 3.42 but now have 3.73?
Means your shift points should be ~8% more aggressive than stock if you have the DRAC/VSSB corrected and the OE sized tires. Since part throttle shifting is based off MPH. If the DRAC/VSSB is not corrected for the error it is shifting in relation to the stock output speed on the transmission aka lower road speed but same rpm as stock.
