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Its Good To Be Tha King
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Discussion Starter #1
So I purchased a set of one and seven eights, long tube headers, and had them professionally installed at my local shop. I can't say enough good things about the knowledgeable installers who have installed all my suspension and exhaust bits. They do wonderful work, treating all vehicles with respect. Install went off without conflict, everything was quickly installed. All the parts we needed were on hand and all the pipe work fell into perfect placement. After the install, the first thing I did was change the tune on my Cortex, down to the Rotofab 87 octane tune. I left all the advanced settings the same, fifty percent shift torque, raised speed and rev limiters, stock shift points, and Superchips values for all the others.

Now my first problem: I'm experiencing some strange shifting issues, mainly on the first to second gear change. It's happening around one half to two thirds throttle, and really shows it's ugly head at wide open throttle. Before the headers, it would occur sometimes, but with more aggressive shift torque settings. It happens right as the gear shift change occurs, instantly the damn car starts to drift sideways! This is not only extremely fun, but it's highly addictive!

And while I'm positive I look stunningly cool sliding sideways, this leads to my second problem: I can't get no kind of traction! It seems like my tires are greased up, which is causing me to purchase more aggressive tires, NT05 275/35/19's should do a better job, and are currently on order.

Along with the cost of two new tires for the rear, I'm seeing additional expenses start to add up, which leads me to my third problem: Gas mileage is at around sixteen miles per gallon average! Now I've traced this directly to the source of the issue and found the cause of the problem, the exhaust now sounds crazy awesome! Especially at a half to two thirds throttle, I cant stay out of it. That sound causing my muscles in my right leg stiffen to a point where the accelerator gets smashed uncontrollably to the floor!

This leads me to my fourth and final problem: I'm getting a slight adrenalin rush like riding a roller coaster every time I'm behind the wheel of my G8! This car is addictive, more now, than ever! I've loved my car since I first laid eyes on her at the dealership with only 2 miles on her odometer, and I still turn around to look at her walking off, five years and eighty three thousand (and climbing) miles later!

This leads me to my fifth problem, I know I said I was done at four, but what could possibly replace her if something terrible were to happen? The only answer I keep coming up with, is another Pontiac G8. This car was the best bang for the buck at purchase, and five years later, she's still holding value unlike any of my other past vehicles.



If anyone is experiencing the same symptoms, please feel free to share. Maybe together we can work through this rough time.
 

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Sarcasm Personified
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3,900 Posts
Here is problem 6: You need a real tune, other than that, yeah I experienced those same problems, until I saw a GHIG 5.0 and things went from there.

Sounds like you are enjoying the hell out of it though, I would too if I had the unicorn of the G8's.
 

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Its Good To Be Tha King
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Discussion Starter #3
Guessing I should see around a 20whp bump in power when upgrading to a custom tune, and yes, that will only add to problems one to five :)

Oh what shall I do? lol

Luckly my LTFT's are acceptable until I can get her professionally tuned.
 

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Ha, for the first bit I thought this was serious and extremely concerned but then I quickly realized I share many of these problems!

Sub'd for some answers and solutions!
 

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1,245 Posts
+1 on a real tune.
 

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You'll pick up about 20 more rwhp with a custom tune but I have good news for you, that Cortex tuner is NOT running your car lean.

When I just got mine tuned they dynoed the car before they started tuning and with my Kooks 1 7/8 LT, no cats, stock mid pipe, Solo axle backs and a Vararam intake the car put down 337 hp at the rear wheels and the Cortex tune was actually fat every where but off idle where it went a little lean, but as the tuner said to have it go lean for a couple hundred RPM off idle wouldn't hurt anything cause its not there for very long and doesn't have much of a load on the engine.
 

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Yep, that just happened..
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I've had all those symptoms for the last 5 years..Also have another one, maxedoutvisaitus....
 

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lol......... what problems to have :)..... I feel sorry for you man....
 

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You missed one other problem, pull down the visor mirror. There is that grin on you face that doesn't go away.
 

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Premium Member
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Sounds normal to me. Take 2 Viagra and don't call me in the morning!
 

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Premium Member
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Sorry to hear about all your "troubles" ... I must say my results were similar, with the exception of #2, I had gotten a big boy tune by then. :wink2:

The gas mileage is directly proportional to the ratio of "normal driving" verses "WOT".

I was scared to read that your "problems" may have been metal-on-metal or clunking problems or something related to the headers installed... but glad to hear that is not the case.

AND GET THAT WIDEBAND INSTALLED ASAP!
 

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I got around 20 mpg HWY when I had LTs and cortex. I removed it for stock tune and it went back to 25.
Got Pat G tune, went to 27 and gobs more power and smoother drive ability.


Sent from AutoGuide.com App
 

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+1 get a real tune
+1

You think your car is fun now? Wait till you get a real tune done on the dyno. It will also drive nicer, yet will be more aggressive when you want it to be. Canned tunes are not capable of correctly tuning your car once you've crossed into LT Header land.
 

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Premium Member
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tune tune tune.

You yourself admitted that you outgrew the cortex, so why do your otherwise-awesome-car the disservice of a tune that is not optimized to what you're running now?
 

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GOT VTAK?
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Real tune and you will really have issues.
 

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What brand of LT's did you install? I would hate to fall for peer pressure, but I will soon, very soon. I'm just waiting to have the cash for the Headders and a dyno tune.
 

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Its Good To Be Tha King
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Discussion Starter #20
I went with the OBX 1 7/8" kit for under $800 shipped. I couldn't help to purchase at that price. Everything fit's nicely.
 
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