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Discussion Starter · #1 · (Edited)
Hi All-
Owned my first V now 2 weeks. It's also my first LS car. already needs more power. Truth be told, I want to quiet the exhaust down, and make the car more livable. Maybe some resonators to reduce drone and/or put stock mufflers back on but leave the cutouts. hopefully these won't restrict the power too much? I rode in a 850 hp V that had stock mufflers so I assume not.

The car was built shortly before purchase. I need to find out what my next mod for more power would be? Car gets driven on the street only, maybe 1 strip run per year. I also moderately daily this car.
Can you tell me any limitations on this build and what to watch for when increasing power? What would be my next cost effective way to make power without buying a 7000.00 blower? Fuel system limitations?

-LS9 GM PERFORMANCE CNC HEADS
-BILLY BRIGGS 416 STROKER (DIAMOND PISTONS/CALLIE H BEAM RODS)
-Custom PD Blower Cam
-Trunion upg
-Hardened pushrods
-Matching Springs for cam
-LS9 Head gaskets
- ARP Head studs
-SFI Flywheel and Balancer
-9.2 Lower
-2.55 Upper
-Ported Snout
- ZL1 lid With reinforced Brick
-LS3 Throttle Body
-Airraid intake
-American Racing 1 7/8 headers
  • 3" X PIpe and Magnaflows (with QTP Cutouts)
  • Squash Dual intank with hobbs switch on 2nd pump
-Upgrated Fuel lines, regulator
  • Flex Fuel
  • ID1300X injectors
  • Black Market Racing Underhood Icebox with LPE HX Pump
  • Weapon X Heat Exch
  • Tim King Built Trans
  • Car was plumbed for Meth at one point...still on the car but disconnected.
 

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Wow nice mod list! Billy builds great engines!
As far as more power, I’d port the blower, 102mm tb and 5” intake. Hook the Meth up and let her eat.
 

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2014 CTS-V Sedan with Heintz Racing 700 HP Package. Red Obsession Tintcoat, Auto Transmission
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Stock mufflers won't reduce the hp. If anything I would be running 2" headers vs the 1-7/8" with your mod list. If you're running headers the stock mufflers will be loud enough for a daily driver and actually sound pretty good.
 

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2012 Wagon A6
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Cant remember if porting those heads net any gains but something to talk with companies about.

So maybe port the heads
Race port on the blower
102 or 103mm throttle body
DDP Intake


Then you'll be maxed out on the blower where the only thing after that is a bigger unit or power adder like nitrous or meth.

Your pulley ratio is already at 3.60. (I would stay close to this) I believe from my reading 3.82 is max (using a 6,500 redline) so with your current combination, a 2.45 upper would put you right below that (3.76). Would increase you maybe 1 psi and be putting the blower at the MAX speed. You are close to sea level so that helps determine things as you arent being choked on altitude air.

These are just my opinion from reading. Use the search function to find what others have done or talked about.
 

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Cant remember if porting those heads net any gains but something to talk with companies about.

So maybe port the heads
Race port on the blower
102 or 103mm throttle body
DDP Intake


Then you'll be maxed out on the blower where the only thing after that is a bigger unit or power adder like nitrous or meth.

Your pulley ratio is already at 3.60. (I would stay close to this) I believe from my reading 3.82 is max (using a 6,500 redline) so with your current combination, a 2.45 upper would put you right below that (3.76). Would increase you maybe 1 psi and be putting the blower at the MAX speed. You are close to sea level so that helps determine things as you arent being choked on altitude air.

These are just my opinion from reading. Use the search function to find what others have done or talked about.
Many ported heads outperform off the shelf heads. LME, WCCH and LSD to name a few. Just need the hollow intake and Ferrara exhaust valves to get the most from them.
 

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Discussion Starter · #10 ·
Many ported heads outperform off the shelf heads. LME, WCCH and LSD to name a few. Just need the hollow intake and Ferrara exhaust valves to get the most from them.
The GM Performance LS9 CNC ported heads are ported already, but you mean they should be ported more? My first mod list was goung to be RPM 5" intake or DDP 4.5 intake and q 102 TB already since that was the least intrusive mods to start with.
 

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The GM Performance LS9 CNC ported heads are ported already, but you mean they should be ported more? My first mod list was goung to be RPM 5" intake or DDP 4.5 intake and q 102 TB already since that was the least intrusive mods to start with.
The LSA heads.
 

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Many ported heads outperform off the shelf heads. LME, WCCH and LSD to name a few. Just need the hollow intake and Ferrara exhaust valves to get the most from them.
That’s not true, you don’t need hollow intakes on LSA heads, and some don’t recommend them with boosted applications.

Many here are running WCCH heads with stainless solid intake valves, myself included.

I also don’t spin to 7k rpm because of many reasons, stock connecting rod bolts being one of them.


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With that mod list, and you already needing more power,

I'd suggest a Kong 2650 or the new Maggie 2650. It will help feed that extra displacement.

Did I miss what kind of boost pressure you're currently running?

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That’s not true, you don’t need hollow intakes on LSA heads, and some don’t recommend them with boosted applications.

Many here are running WCCH heads with stainless solid intake valves, myself included.

I also don’t spin to 7k rpm because of many reasons, stock connecting rod bolts being one of them.


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The hollow valves definitely been debated, however I am not aware of any failures in boosted spwcific applications. They are sodium filled and transfer heat better. The failures are typically tune or assembly related.
 

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The hollow valves definitely been debated, however I am not aware of any failures in boosted spwcific applications. They are sodium filled and transfer heat better. The failures are typically tune or assembly related.
I guess you would know better then me


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I was not debating with you. I just researched prior to making the decision to use hollow valves.
Well, to be honest, I’ve spent probably over 100 hours talking with Richard and Dave at Wesco Sonder has for many many years, so I trust their input and experience.


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