headers tune/MPG
04-04-2011, 03:44 PM
#95
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Just a quick comment on VVT. GM installs this primarily for economy purposes NOT for power adding advantages. They do this by positioning the cam phase in such a manner that the engine spins easier so its not costing efficiency from pumping unnecessarily hard. So when you have a VVT engine tuned for power the gains are HUGE because two fold. 1. GM tunes lean more towards efficiency than power 2. VVT is a power adder so using it for power instead of efficiency is the double hit.
So to see mileage drops more than say a modded/tuned older 5.3 or 6.0 or any LS engine that was non VVT is going to be part of the result. Having an all out performance tune is going to take some of the efficiency away with these VVT engines to be sure.
3mpg does seem pretty harsh though are you sure its not your happy right foot now that your a baller tuned ****?
Seriously though if mileage is a big deal then leave the VVT tables alone and disable torque management and ( if your modded ) dial in your AF and you'll probably have stellar mileage and still make great power. Just not "AS" great as if you dial in the VVT for power as well.
So to see mileage drops more than say a modded/tuned older 5.3 or 6.0 or any LS engine that was non VVT is going to be part of the result. Having an all out performance tune is going to take some of the efficiency away with these VVT engines to be sure.
3mpg does seem pretty harsh though are you sure its not your happy right foot now that your a baller tuned ****?
Seriously though if mileage is a big deal then leave the VVT tables alone and disable torque management and ( if your modded ) dial in your AF and you'll probably have stellar mileage and still make great power. Just not "AS" great as if you dial in the VVT for power as well.
04-04-2011, 04:15 PM
#96
Just a quick comment on VVT. GM installs this primarily for economy purposes NOT for power adding advantages. They do this by positioning the cam phase in such a manner that the engine spins easier so its not costing efficiency from pumping unnecessarily hard. So when you have a VVT engine tuned for power the gains are HUGE because two fold. 1. GM tunes lean more towards efficiency than power 2. VVT is a power adder so using it for power instead of efficiency is the double hit.
So to see mileage drops more than say a modded/tuned older 5.3 or 6.0 or any LS engine that was non VVT is going to be part of the result. Having an all out performance tune is going to take some of the efficiency away with these VVT engines to be sure.
3mpg does seem pretty harsh though are you sure its not your happy right foot now that your a baller tuned ****?
Seriously though if mileage is a big deal then leave the VVT tables alone and disable torque management and ( if your modded ) dial in your AF and you'll probably have stellar mileage and still make great power. Just not "AS" great as if you dial in the VVT for power as well.
So to see mileage drops more than say a modded/tuned older 5.3 or 6.0 or any LS engine that was non VVT is going to be part of the result. Having an all out performance tune is going to take some of the efficiency away with these VVT engines to be sure.
3mpg does seem pretty harsh though are you sure its not your happy right foot now that your a baller tuned ****?
Seriously though if mileage is a big deal then leave the VVT tables alone and disable torque management and ( if your modded ) dial in your AF and you'll probably have stellar mileage and still make great power. Just not "AS" great as if you dial in the VVT for power as well.
Even though my tuner mentioned the efficiency that the VVT was originally tuned for, I had forgotten that.
VVT is also tuned for emissions (NoX) reductions as well.
04-04-2011, 05:27 PM
#98
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That makes sense, I always wondered why the VVT 6.2s didn't make more power than their non-VVT cousins.
04-04-2011, 08:54 PM
#99
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Our*07+ long tube headers should be in stock around May 15th.
Sorry we don't have any pricing yet.
The primaries are 1 3/4" and the collectors and Y are 2 1/2"
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[url]http://www.lpparts.com
So I guess PS will be the better pick for low price LT's due to their 3" ORY.
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