Need Help with TM on 2009 4.8L Pickup

It was on a 2011 5.3 same vdf as a 2009

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Originally Posted by roughneck427

It was on a 2011 5.3 same vdf as a 2009

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Roughneck - TC did update the vdf for me with the added tables. I did not have the 2009 4.8L, so I've been playing with my 2012 (which shares the same vdf) and it does seem to respond to the changes. The final timing table does seem to be the biggest game changer, but the 2012 5.3L is very sensitive to timing changes. I'm still tweeking it when I have time and hope to have a attempt ready for the 4.8L truck soon. Thanks again to all and I'm update again once I get the truck back.

Yeah min final timing helps the most on the 6 speed trucks and how I found out on this is I used efi live on my Pontiac G8 I tried same settings I used on my car on a truck and your right they are sensitive it shifted way to hard had to trim it back some

This is a test tune on my 2012 5.3L. It should be close to what you were dealing with.

Thanks,
Steve

Just an update. Truck responded well to raising the minimum final timing, but still is lame from a dead stop. Not sure if I'm missing something or expecting it to be able to burn the tires down and it's simply not capable? Not giving up at this point, but haven't had something whip me like this in awhile.

The stall speed for the torque converter is built low. Tuning helps out. But just a tune your not going tune able to roast the tires. I always recommend a higher stall converter to be able to spin the tires like your asking. That way it will be right in the power curve when you go wot.

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Originally Posted by doctortuned

The stall speed for the torque converter is built low. Tuning helps out. But just a tune your not going tune able to roast the tires. I always recommend a higher stall converter to be able to spin the tires like your asking. That way it will be right in the power curve when you go wot.

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control

That makes sense. I keep thinking GM is regulating the low end performance via ECM, but I guess it's just as possible they lowered the stall for a direct control. Thanks for helping me open up to other possibilities for limited performance. It makes sense!

I doubt GM lowered the TC stall on purpose, the issue is its a GEN 4 4.8 engine that makes very little off idle torque. If you hada 5.3 the same 4.8 TC would stall a bit higher due to the increased torque of the 5.3.

peace
Hog

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Originally Posted by Hog

I doubt GM lowered the TC stall on purpose, the issue is its a GEN 4 4.8 engine that makes very little off idle torque. If you hada 5.3 the same 4.8 TC would stall a bit higher due to the increased torque of the 5.3.

peace
Hog

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Very possible. I have a 2012 with the 5.3L and it's not much off idle either. Still not sure if it can be tuned out or if it simply doesnt have the low end torque as you mentioned.

Thanks!