Reprograming shift points with Hypertech Power Programmer

[p_a_p_i]

Can anyone tell me from experience; what to reprogram my shift points with a Hypertech Power Programmer, on my Sierra. It has a 4.8 liter engine, Flex-a-Lite Fan, throttle body spacer, throttle body bye pass, K&N air filter, Flowmaster; sitting on 20 x 8.5 rims with 275/45 R 20 tires. I know someone out there has the same set up. Please share with me.

[Shortbus]

Only testing on the track will give you the definate answer. I have yet to do it so can't help you, the only thing I did was change 1-2 ^2mph and 2-3 ^1mph and 3-4 ^3mph. No rhyme or reason for this but it seems to work okay, I also set the rev limiter to 5100 rather than 4800 stock.

In the next month or so I am going to take it to Friday night drags at Firebird and monkey with it some to see if I can get a formula together that works for my truck and tire size, and other mods.

[red00lght]

Papi,

A little off-topic, but I've got the same engine and was wondering if you felt any difference from the t.body spacer or bypass mods? Thanks

[jeverett]

I have a 99 Z71 5.3 and my shift points are 1-2 +4 mph, 2-3 +12mph, and I left 3-4 shift at +0

[billmjones]

i have the vortec 5.3 and i have dropped the shift points to get rid of the dead band where the engine is running out of cam. 1-2= -2, 2-3 = -4; 3-4 = 0. has anyone one else done this? every where i read seems people are increasing shift points. mine seems respond better lowering them tho, just a thought.

[jeverett]

I might try that and see how it works.