HP LS3 question.
Thread Starter
Le Mans Master
Joined: Jun 2011
Posts: 8,049
Likes: 329
From: Charlotte NC
St. Jude Donor '14-'15
HP LS3 question.
2008 LS3 Z51 automatic, I have a BTR Stage 1 cam kit, springs, locks all that stuff. 2009 ZR1 full 3" dual mode exhaust, real CAI. I'm getting 423 to the wheels with a tune. Will replacing the TB give me some more HP and then will I have to pay for another Dyno tune? Are there any other things to do (cheaply) that I can do for more power? Not interested Interested in long tube headers. 
Melting Slicks
Joined: Oct 2015
Posts: 3,299
Likes: 769
From: Mead Wash
2020 C6 of the Year Finalist - Modified
C6 of Year Finalist (appearance mods) 2019
Hp
LT’s will get you another 35 to 40. As far as another tune depends if your original tuner tuned out the rear O2 sensors.
Team Owner
Joined: May 2006
Posts: 21,473
Likes: 356
From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
What DYNO was your Vette tuned on? remember it's not really about numbers - it's about peak performance
You could also do a Rod Mod and ported LS3 manifold and a Meziere EWP and a Under Drive Pulley set (10% or 25% UD) - some examples below
https://gwatneyperformance.com/produ...-manifold-mod/
https://www.c6performance.net/catalo...-p-497956.html
https://www.c6performance.net/catalo...-p-503187.html
https://rpmspeed.com/pulleys-balance...98vkr6qfb8rjq4
https://www.texas-speed.com/c-3357-p...ette-2008.aspx
My 2009 A6 Dyno'd at 452 RWHP and 422 RWTQ with the following mods:
VARARAM
VMAX Ported TB
Rod Mod and Ported LS3 Manifold
Meziere EWP
PatG Cam .600" 222/230 116LSA (Stock LS3 Heads with Dual Springs)
NGK TR5IX Plugs
Taylor 8.5mm wires (Blue)
2012/2013 - ZR1/Z06 exhaust manifolds, 2012/2013 - ZR1/Z06 3" Downpipe Cats, and 2012/2013 3" ZR1/Z06 Catted X-Pipe (4 Cats total)
Factory NPP exhaust (2.5")
3.42 Z06 Rear
YANK SS3200 Stall
Dyno Tuned - results listed above
Thanks,Matt
You could also do a Rod Mod and ported LS3 manifold and a Meziere EWP and a Under Drive Pulley set (10% or 25% UD) - some examples below
https://gwatneyperformance.com/produ...-manifold-mod/
https://www.c6performance.net/catalo...-p-497956.html
https://www.c6performance.net/catalo...-p-503187.html
https://rpmspeed.com/pulleys-balance...98vkr6qfb8rjq4
https://www.texas-speed.com/c-3357-p...ette-2008.aspx
My 2009 A6 Dyno'd at 452 RWHP and 422 RWTQ with the following mods:
VARARAM
VMAX Ported TB
Rod Mod and Ported LS3 Manifold
Meziere EWP
PatG Cam .600" 222/230 116LSA (Stock LS3 Heads with Dual Springs)
NGK TR5IX Plugs
Taylor 8.5mm wires (Blue)
2012/2013 - ZR1/Z06 exhaust manifolds, 2012/2013 - ZR1/Z06 3" Downpipe Cats, and 2012/2013 3" ZR1/Z06 Catted X-Pipe (4 Cats total)
Factory NPP exhaust (2.5")
3.42 Z06 Rear
YANK SS3200 Stall
Dyno Tuned - results listed above
Thanks,Matt
Thread Starter
Le Mans Master
Joined: Jun 2011
Posts: 8,049
Likes: 329
From: Charlotte NC
St. Jude Donor '14-'15
My car is an 08 so I will need to see if the blade is gold or silver, early or late model 2008, correct? I just want to port and polish I understand that there is no HP gain from this just throttle response will improve.
Race Director
Joined: Mar 2011
Posts: 13,262
Likes: 3,150
From: SW Florida
2021 C6 of the Year Finalist - Modified
If you don't increase the size of the actual throttle plate in a throttle body, I can't see how you are going to get any increase in HP or torque on a non-boosted engine.
You can port, shine and polish all you want, but you are still going to pull air through the same size orifice (throttle plate) ... you can only pull so much air through a certain size hole.
Wanna get more airflow through the throttle body? .. simple; . get a throttle body with a larger diameter throttle plate.
____________________________
Any particular throttle body will only flow as much air as the narrowest section of the throttle body ... and the narrowest area is where the throttle plate is located.
.
You can port, shine and polish all you want, but you are still going to pull air through the same size orifice (throttle plate) ... you can only pull so much air through a certain size hole.
Wanna get more airflow through the throttle body? .. simple; . get a throttle body with a larger diameter throttle plate.
____________________________
Any particular throttle body will only flow as much air as the narrowest section of the throttle body ... and the narrowest area is where the throttle plate is located.
.
Last edited by Turbo6TA; Mar 23, 2021 at 09:58 PM.
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Pro
Joined: Jan 2014
Posts: 706
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From: Houston TX
Look up LS3 intake manifold "Rod Mod". If you are doing the TB, you might as well get the intake ported and the rod-mod performed. You would definitely feel the HP gains over just a TB
With the BTR stage 3 cam, ported heads, and intake/tb mods, i put dow 512rwhp on a mustang dyno. M6 LS3
With the BTR stage 3 cam, ported heads, and intake/tb mods, i put dow 512rwhp on a mustang dyno. M6 LS3
Last edited by GS_DAN; Mar 23, 2021 at 10:09 PM.
Thread Starter
Le Mans Master
Joined: Jun 2011
Posts: 8,049
Likes: 329
From: Charlotte NC
St. Jude Donor '14-'15
It has always been my understanding that you port (remove obstacles) and polish (smooth out) the inside of a throttle body to have a smoother less turbulent air flow. This having the effect of a better acceleration, not necessarily more horsepower. 
Thread Starter
Le Mans Master
Joined: Jun 2011
Posts: 8,049
Likes: 329
From: Charlotte NC
St. Jude Donor '14-'15
The Internal Combustion Engine can be looked at as a large (6.2 liter) air pump. The ideal situation is that you have the hole where the air is being sucked in be equal to the hole where the air is being pushed out. This is the simplest way I can come up with to describe it. Though it is much more complicated than my description. My porting and polishing idea is just to smooth out that air flow, making it less restrictive. The ZR1 exhaust system I have installed on my car is big enough to handle almost anything I can put on the "air in" side of the engine. Making the hole bigger on the air in side would probably just increase my fuel costs and not do much for my power gains. Unless I installed a devise that would Force the air into the motor.
Team Owner
Joined: May 2006
Posts: 21,473
Likes: 356
From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
https://gwatneyperformance.com/produ...-body-porting/
Thanks,Matt
Race Director
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From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
Ported TB made 0 difference on my '08 A6. Back to back 1/4 mi passes. Two with stock TB, swapped to the ported TB and made two more passes. Lotsa luck expecting more power or quicker response.
Race Director
Joined: Mar 2011
Posts: 13,262
Likes: 3,150
From: SW Florida
2021 C6 of the Year Finalist - Modified