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Discussion Starter #1
I finally got my car tuned and had alchemy here in Florida install my SLP headers.
the SLP headers bolted in so easy to stock mid pipes they look amazing.
I have AFE cold air intake and dynomax axle backs.

on pump gas tune it made
335hp and 352tq

the tranny tune is amazing what a different car.


anyone install a Fast intake manifold and larger throttle body and dyno your G8?
thinking about doing FAST
183326
183327
intake and Injectors next.
 

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I've been watching this guy's channel and came across this. 1st part is the LS3 versions we would probably consider. To me, it tells me that the stock LS3 is a very good piece. And since I rarely wind this thing much over 6,000, I want all the low/mid I can get my hands on. To me, what you get at the very top doesn't justify what I have to give up down low/mid
 

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Discussion Starter #3
so basically good unless doing 1/2 mile roll racing for top end?
I'm surprised how much HP people are making with just bolt ons.
I have intake headers and axle backs with tune ,and only made 335hp 352tq and in only have 40k miles on my car.
how is everyone making 350-370 to wheels with just intake and kooks..i know their better headers bit kot 20hp more than my SLPs
what other boltons can I do? the OEM mid pipe exhaust i hear vs corsa is only 1-3hp less.
I dont want to put a cam in it.
 

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Depends on the dyno. 335 whp x 1.18 is about 400hp. That's 35hp over stock with mid pipe headers and tune.

For easy bolt ons, not sure. Sure cam is a pain. Maybe a set of higher ratio rockers? What's the upgrade? 1.8 ratio?
 

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Discussion Starter #5
Depends on the dyno. 335 whp x 1.18 is about 400hp. That's 35hp over stock with mid pipe headers and tune.

I only have SLP headers hollow cats
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,CAI and dynomax muffler with dyno tune
.so is this ok numbers?
how come I see so many people over 350+hp with just headers and CAI?
183331
 

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If you still have the stock exhaust behind those headers, that is what chokes you off. Injectors are not holding you back, LS3 runs the same. A rod mod intake would do more for you until you get a big cam. Then you can use a fast intake. Removing restrictions is basic modding. I would recommend a Saxon Maf screen, porting the throttle body and a full 2.5” exhaust . No restriction going in or out.
Can you get a scan of you wot tune. Would help to see your fuel/air ratio and timing. Also what’s your oil pressure at idle. If your oil pump is sucking air past the O ring , the your not getting full valve lift. Any lifter tick?
 
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Discussion Starter #7
If you still have the stock exhaust behind those headers, that is what chokes you off. Injectors are not holding you back, LS3 runs the same. A rod mod intake would do more for you until you get a big cam. Then you can use a fast intake. Removing restrictions is basic modding. I would recommend a Saxon Maf screen, porting the throttle body and a full 2.5” exhaust . No restriction going in or out.
Can you get a scan of you wot tune. Would help to see your fuel/air ratio and timing. Also what’s your oil pressure at idle. If your oil pump is sucking air past the O ring , the your not getting full valve lift. Any lifter tick?
lifter tick? my car only has only just turned 40k original miles.
also the midpipe as I stated early when swapped put with corsa midpipe only made 3hp more that's it!
my axle backs are only thing I may change but I like mine since there is any drone..
 

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Mileage doesn’t matter, our cars are over ten years old. If the oil pump pick up O ring leaks. The oil gets air in it . The lifters won’t open the valves fully.
 

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Discussion Starter #9
Mileage doesn’t matter, our cars are over ten years old. If the oil pump pick up O ring leaks. The oil gets air in it . The lifters won’t open the valves fully.
no lifter tick cat literally came back from a well know shop here and the owner and mechanic said the car is extremely clean..no leaks anywhere..I dont drive my car in rain and its garage for both owners.
I think the 370 to wheels is bs.
I have early 2009 6vin# is NOT a 3..and indont have the push out cup holders..so mine came with 2 cats only and 361hp factory
 

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While "numbers "are nice and all, the relative change from before is the important thing.
That and if the shop you used sees typical numbers on their machine all the time that are higher.

There may be lost power in those collectors. Super short, no merge, instantly opening up into the gutted collectors.
 

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Discussion Starter #11
While "numbers "are nice and all, the relative change from before is the important thing.
That and if the shop you used sees typical numbers on their machine all the time that are higher.

There may be lost power in those collectors. Super short, no merge, instantly opening up into the gutted collectors.

these SLPs made same hp as KOOK mid lengths.
I just literally bought because of this thread a BORLA STYPE cat back system part#Borla 140287

183334
 

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Ok , guess you got all handled then(y)(y)
 

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Forced induction is your friend.....
 

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Then LS7 is your friend.
Mild cam, headers, = 560 rwhp
 

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Discussion Starter #17
Then LS7 is your friend.
Mild cam, headers, = 560 rwhp
my gt only has 40k original miles I dont wanna so a swap. I have a DART SHP 427 stroker in my truck i would put a holly efi kit on it if i was going to do a swap but i want to keep the OEM engine.

seems like the L76 and LS3 intakes are exactly the same runner size and no power gains.
guess only thing left is to do rockers..I dont want to change cam yet.
 

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Why are you so adamant about not doing a cam? The ticking time bomb AFM/DOD should be more than enough of a reason to do a swap as it can give out any minute. You can even just do a straight factory ls7.cam without getting crazy chop or affecting drivability. I see it as more of a preventative maintenance with a bonus of gaining a little hp along the way. There a ton of other variables that could give you lower hp numbers than others, elevation, temperature, the gas you used, the dyno you used (and the tuner).

Either way, they're respectable numbers and I'd be ok with those personally.
 

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L76 is a hodgepodge of LS parts. It's an LS2 block, with L96 heads and an LS3 intake manifold. And not to mention that DoD/AFM hardware everyone is trying to get you to get off of. It truly is a ticking time bomb, mileage isn't the issue. Motors have gone with as many miles as you have now when the car was only a year old.
 
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