PDA

View Full Version : Superchips Cortex installed



2009blueg8gt
02-16-2009, 03:58 PM
well i went ahead and done it after going back and forth on a vms,hp,sc, tune survey says cortex i like how smoothe it made my revs,and no more hesitation or lags when you floor it now so i am very happy with my selection so if you see a 09 stryker blue running around the dallas ft.worth area "LOOKOUT" cause im ready.........!!!!!!!!!!!:woohoo::woohoo:

Devilish34
02-16-2009, 04:16 PM
well i went ahead and done it after going back and forth on a vms,hp,sc, tune survey says cortex i like how smoothe it made my revs,and no more hesitation or lags when you floor it now so i am very happy with my selection so if you see a 09 stryker blue running around the dallas ft.worth area "LOOKOUT" cause im ready.........!!!!!!!!!!!:woohoo::woohoo:

Did you do a comparison 0-60/ 1/4 mile before and after?

bwooten492
02-16-2009, 06:28 PM
well i went ahead and done it after going back and forth on a vms,hp,sc, tune survey says cortex i like how smoothe it made my revs,and no more hesitation or lags when you floor it now so i am very happy with my selection so if you see a 09 stryker blue running around the dallas ft.worth area "LOOKOUT" cause im ready.........!!!!!!!!!!!:woohoo::woohoo:

Go put it on a dyno...

SRG963
02-17-2009, 06:40 AM
Did you do a comparison 0-60/ 1/4 mile before and after?

Good idea.

To do this, flash back to the stock tune and data log to compare :)

SRG963
02-17-2009, 06:44 AM
well i went ahead and done it after going back and forth on a vms,hp,sc, tune survey says cortex i like how smooth it made my revs,and no more hesitation or lags when you floor it now so i am very happy with my selection....

Just wait, the 93 Octane tune and CAI specific tunes are on the way!

We should end up with a pretty nice hand held tuner if they keep taking my suggestions :)

JerzeyGT
02-17-2009, 07:00 AM
They will have web based updates for the tuner??

SRG963
02-17-2009, 07:06 AM
They will have web based updates for the tuner??

Yes

Superchips Cortex programmers are essentially never out of date with regular, free updating of the units exclusively at Superchips.com.

Superchips consistently re-engineers their calibrations to stay in-line with the new calibration files OEM manufacturers release and makes them available at no cost to their customers.

JerzeyGT
02-17-2009, 07:43 AM
OOOoo.... So how do u think this would compare with a dyno tune.. I was looking into getting a tune after I purchase the Vararam system(after u guys test it out) But I like the fact u can bring it back to stock if needed, instead of going back to the place that tuned your vehicle....

I am just skeptical with handhelds because I was not impressed when I had the Hypertech for my silverado.... How much do they run $$$

SRG963
02-17-2009, 07:52 AM
OOOoo.... So how do u think this would compare with a dyno tune.. I was looking into getting a tune after I purchase the Vararam system(after u guys test it out) But I like the fact u can bring it back to stock if needed, instead of going back to the place that tuned your vehicle....

I am just skeptical with handhelds because I was not impressed when I had the Hypertech for my silverado.... How much do they run $$$

Nothing compares to a Dyno tune done by a professional IMO.

The Vararam system will need a special tune.

The hand held is great for daily drivers with small mods.

The Cortex runs $429, but with my code it's $343 shipped to your door.

They have a 30 day money back guarantee if it's not what you want.

Devilish34
02-17-2009, 07:54 AM
Just wait, the 93 Octane tune and CAI specific tunes are on the way!

We should end up with a pretty nice hand held tuner if they keep taking my suggestions :)

Ahh so there is no cai tune yet....not that I have my new era cai :footstomp:

SRG963
02-17-2009, 08:04 AM
Ahh so there is no cai tune yet....not that I have my new era cai :footstomp:

Not quite yet, each style kit will require it's own specific tune due to maf locations.

The current 93 Octane tester also has a NEP CAI like we do, and I believe Superchips will be creating that CAI tune first.

Chewy
02-17-2009, 08:15 AM
each style kit will require it's own specific tune due to maf locations.


Didn't I say this a week ago and get corrected for being wrong? :nud:

:)

JerzeyGT
02-17-2009, 08:17 AM
Nothing compares to a Dyno tune done by a professional IMO.

The Vararam system will need a special tune.

The hand held is great for daily drivers with small mods.

The Cortex runs $429, but with my code it's $343 shipped to your door.

They have a 30 day money back guarantee if it's not what you want.

I dont want to be a pain in the ass but I have a couple questions... As far as mods go I am just going to get an intake and if any one comes out with a catback with single outlets, I would get an exhaust also... Thats as far as I plan on going... As far as a special tune for a Vararam is that somthing you see them comming out with an update for.... Im asking you because it seems like you have some pull over there........

SRG963
02-17-2009, 08:35 AM
Didn't I say this a week ago and get corrected for being wrong? :nud:

:)

You weren't corrected by me my friend :)

SRG963
02-17-2009, 08:42 AM
I dont want to be a pain in the ass but I have a couple questions... As far as mods go I am just going to get an intake and if any one comes out with a catback with single outlets, I would get an exhaust also... Thats as far as I plan on going... As far as a special tune for a Vararam is that somthing you see them comming out with an update for.... Im asking you because it seems like you have some pull over there........

Magic 8 Ball says chances are good! :)

I see update tunes in the near future for each style CAI kit including the Vararam unit.

Was there another question I missed? Feel free to ask questions, as it helps everyone.

Devilish34
02-17-2009, 09:06 AM
Feel free to ask questions, as it helps everyone.

Why is the sky blue?

bwooten492
02-17-2009, 09:10 AM
OOOoo.... So how do u think this would compare with a dyno tune.. I was looking into getting a tune after I purchase the Vararam system(after u guys test it out) But I like the fact u can bring it back to stock if needed, instead of going back to the place that tuned your vehicle....

I am just skeptical with handhelds because I was not impressed when I had the Hypertech for my silverado.... How much do they run $$$

\I had the programmer on my car and I lost 4HP and 8LBS of TQ. Then I got a real tune and gained 19 over the superchips.

SRG963
02-17-2009, 09:12 AM
Why is the sky blue?

Not blue, it's black with white dots!

2009blueg8gt
02-17-2009, 11:45 AM
OK OK OK i know i didn't do the dyno thing right,i am so impatient when it comes to stuff for my car ,...for example i didnt want to drive my car until my wheels came in two days later..........call me a bratt but that's just the way i am......and by the way changed my tires today ang got the 1-2 gear chirp ive been waiting on..........

Devilish34
02-17-2009, 12:11 PM
New tire chirp or more power chirp?

2009blueg8gt
02-17-2009, 02:51 PM
lol both but my other tires only had a few thousand miles on them ........so more power.......

antonio31
02-18-2009, 05:00 AM
well i'm one of the guys who will be loaning my car over to superchip to get the 93 octane and nep cai tune done, once i get it back i will let everyone know what numbers i got for hp and tq from the 93 octane tune (hopefully superchips give me those numbers). Right now i'm just setting up a time and date when superchip wants to do the tune on my car. i'm sorry i just can't believe that someone will lose hp and tq with a programmer by a pretty good company if anything i would think you probably wouldn't gain as much as you would with a dyno tune. I'll know if this tune did anything when i head to the track friday. i

mpostr
02-27-2009, 07:41 AM
I just installed this in my car bone stock 09 gt with sport package and here are my findings - first i renamed it cotex as this would be more appropriate as far as i can tell - number one, i have read about all this excessive wheel spin in the forums - i dont see how - areyou in 20 degree weather - i am in houston and i have the 19in wheels - no wheel spin - the shifts do shift better but as far as power i think it is a miscoception - the revs have been lifted and the shifts are harder(still pretty soft though). I have it installed on the performance tune with 100% superchips value for shifting. I have only done a 10 minute drive with it but so far I am disappointed. I also will get a vararam from patrick and i believe that the intake alone would probably create more power than this program does. I am not a rookie to building extremely fast cars and have raced spo in the scca southeast region for 9 years so I know how it should have felt. my conclusion is if you are a street guy and dont really know or care for air/fuel ratios then this is ok. If you are educated about power you will dyno tune like i am about to and take the 11.0 into the 12.5 to 13 range with your fuel mixture, advance timing and make a screaming (safe) demon out of your ride. I am including a picture of my last spo car - it is a 72 datsun 240 with a imsa kit a stroked l32 and a t04s trim turbo making 686rwhp at the dyno in the pic - now this thing was fast - oh yeh - 2200lbs

elbison
02-27-2009, 09:34 AM
Why would you buy a Cortex if you want to go 11s in a G8 GT?

I think it's pretty cool -- I just installed it yesterday in my wife's car, and am only using 50% shifting and it's impressive to me.

But, I am only looking for 350rwhp+ and high 12s (w/ adding ARHs and Vararam).

mpostr
02-28-2009, 07:03 AM
i never said i wanted to go in the 11's. i am not a drag racer, i am a road racer and care more about overall driveability - for you guys that buy this for "your wifes car" it probably is a good product. Im not giving up on it just yet but i am going to play around wiyh it a bit and see what happens - ill post my findings

PantherGTBlack
02-28-2009, 08:51 AM
Why would you buy a Cortex if you want to go 11s in a G8 GT?

I think it's pretty cool -- I just installed it yesterday in my wife's car, and am only using 50% shifting and it's impressive to me.

But, I am only looking for 350rwhp+ and high 12s (w/ adding ARHs and Vararam).

mposter was referring to the air/fuel ratio. I did install the cortex temporarily to be able to mess lightly with the shift settings. Once I do a maggie or a cam, ill get a real tune. but for people that are wanting to keep their car close to stock, the cortex is the way to go, especially if you took advantage of the discount code.


mposter, you're supposed to to give the tranny a couple of days to learn how to deal with the new shifting tables the cortex installs...surprised you didn't know that considering the experience you state to have, not hatin' just sayin.

elbison
02-28-2009, 09:13 AM
Yeah, I realize he was talking A/F. I guess my statement regarding going 11s was just to mean I don't think the cortex is meant for serious drag racers.

SRG963
02-28-2009, 09:20 AM
Yeah, I realize he was talking A/F. I guess my statement regarding going 11s was just to mean I don't think the cortex is meant for serious drag racers.

You are correct.

As I stated many times, so no one could get it twisted, the Cortex is good for a lightly modded Daily Driver. Lightly modded meaning CAI kits and cat or axle back exhausts. The tunes for the CAI kits are on the way, 2 out of the 5 styles should have a tune within 2 weeks.

You want to heavy mod and track it, see Vector :)

SRG963
02-28-2009, 09:30 AM
...number one, i have read about all this excessive wheel spin in the forums - i dont see how - areyou in 20 degree weather - i am in houston and i have the 19in wheels - no wheel spin

My weather is 10 degrees cooler than your weather, and much less humid. Humidity will help the tires stick.

My spin is when I want to drift. I turn the car sideways and go WOT in manual first or second gear to do this. Usually first into second, and she will burn the tires off if I choose to do so.

PantherGTBlack
02-28-2009, 12:29 PM
You are correct.

As I stated many times, so no one could get it twisted, the Cortex is good for a lightly modded Daily Driver. Lightly modded meaning CAI kits and cat or axle back exhausts. The tunes for the CAI kits are on the way, 2 out of the 5 styles should have a tune within 2 weeks.

You want to heavy mod and track it, see Vector :)

I hope one of those is for the NEP CAI!

SRG963
02-28-2009, 12:46 PM
I hope one of those is for the NEP CAI!

The first released will be the NEP CAI, which also works for OPG and Spectre.

The second will be the NEP OTR, and it will be out very shortly after the first.

The 93 Octane tune will also be out with the first NEP CAI tune.

PantherGTBlack
02-28-2009, 12:55 PM
Schweeet, thanks Shawn.

locrzn#92
02-28-2009, 03:39 PM
I'm waiting with anticipation. I love the torque, hopefully the 93 tune with the cai will help lean this thing out. Its really rich, even more then the stock tune.

mpostr
03-02-2009, 10:14 AM
ok - i have now driven the car some and set the shift to 125% value - i must admit that the car is coming to life the more i drive it. I am impressed for the money i spent on this tuner now that the car is actually learning the setup. it did chirp the tires hitting third today. I am going to put the vararam intake on the car with the tune at stock and then performance and data log it. Being that the vararam is the only intake that actually richens the fuel mixture I am interested to see what happens here. I have spoke to Patrick at Vararam about this and he is interested to see as well since i live in houston. We will keep all posted!! So, again for the money this is a pretty nice little device and the torque management (or lack there of) is awesome:)

RxApple
03-05-2009, 01:06 PM
My wife says my cortex arrived today, can't wait to get home and use it!!! I am very excited!!!! T-1hour

BigRob
03-05-2009, 01:24 PM
on the 91 tune, does it raise the max rpms automatically? i really want to keep it at 6k, ive heard there is some premature wear on some internals if it is surpassed.

SRG963
03-05-2009, 01:27 PM
on the 91 tune, does it raise the max rpms automatically? i really want to keep it at 6k, ive heard there is some premature wear on some internals if it is surpassed.

On all the Cortex tunes, you can set shift points where you want them to be, from stock to the raised value.

BigRob
03-05-2009, 01:34 PM
right on, so with the preprogrammed 91 tune, itll stay at 6? i really wanna order already, but drcustoms got me a bit worried with the jerkey shifts he was talking about, but like anything else, it seems you have pull over there and can probably get it worked out, no doubt

BigRob
03-05-2009, 01:35 PM
My wife says my cortex arrived today, can't wait to get home and use it!!! I am very excited!!!! T-1hour

FEEDBACK!! lol

SRG963
03-05-2009, 01:37 PM
right on, so with the preprogrammed 91 tune, itll stay at 6? i really wanna order already, but drcustoms got me a bit worried with the jerkey shifts he was talking about, but like anything else, it seems you have pull over there and can probably get it worked out, no doubt

Don't worry about any shifting problems, I truly have had none.
Everything has gotten better since the tune.
Idle is smooth now at stops, and it shifts very quick at all throttle positions.
The 93 Octane tune should be released soon.

z51l9889
03-05-2009, 05:11 PM
I got my Cortex today and installed the 87 octane tune with everything at Superchips default. The shift firmness went up quite a bit and it generally seems to shift quite a bit better. I am getting a bit of a flare on the upshift but the delay after the shift is pretty much gone. I've only driven about 5 miles on the tune so I obviously need to let the TCM learn the new settings before I make any changes. Also, I only have 500 miles on the car so I'm sure things will change a bit as it fully breaks in.

One question -- when I select an option, the tuner comes back with "Superchips" setting. To adjust, do I press the up and down arrow keys?

TIA

SRG963
03-05-2009, 05:37 PM
One question -- when I select an option, the tuner comes back with "Superchips" setting. To adjust, do I press the up and down arrow keys?

TIA

Yes, you scroll up and down, left is exit or back, and right is continue I believe.

SLVRG8GT
03-06-2009, 05:41 AM
Yes, you scroll up and down, left is exit or back, and right is continue I believe.


Thats how I do it! :) Where's my 93 O tune SRG :watch:

SRG963
03-06-2009, 06:36 AM
Thats how I do it! :) Where's my 93 O tune SRG :watch:

I've sent several emails trying hard to get the 93 tune out today, but as of late yesterday, the engineer was still tweaking things.

We should see this released next week I believe.

locrzn#92
03-06-2009, 10:34 AM
Thats gonna be awsome.

red1997zq8
03-06-2009, 10:49 AM
Thanks for all the answers shawn

ThugHunter
03-11-2009, 01:21 PM
I think we should all call and threaten to return our Superchips under their 30 day return policy and maybe then they'll release this 93 octane tune and cai specific tune.

In all seriousness, I can't wait to receive my Cortex tomorrow. And I can't imagine if I had to wait as long as some of you have for the 93 octane tune.

locrzn#92
03-11-2009, 01:32 PM
To be serious the 91 octane is pretty awsome. Just install and you'll see, not all hp, but a shit load of torque and great shifts. To me thats just fine, if the 93 octane turns out to work well then thats just a plus and I'm ready for it when it happens. If nothing else this tuner gives us all a chance to learn about the computers in these cars that we didn't understand before. It turns off the dod, torque shift levels, stock tune, 87 tune, 91 tune, raise the revs, take of the top speed limiter and maybe soon 93 octane. If you have it tuned at a shop you have to take it back to have these things done. Yes they can make more hp, but, this tuner lets us control the way we drive everyday. Thats a plus for me and most of us. Be patient, like the SGR said its coming and I think we will all like it.

ThugHunter
03-12-2009, 03:00 PM
To be serious the 91 octane is pretty awsome. Just install and you'll see, not all hp, but a shit load of torque and great shifts. To me thats just fine, if the 93 octane turns out to work well then thats just a plus and I'm ready for it when it happens. If nothing else this tuner gives us all a chance to learn about the computers in these cars that we didn't understand before. It turns off the dod, torque shift levels, stock tune, 87 tune, 91 tune, raise the revs, take of the top speed limiter and maybe soon 93 octane. If you have it tuned at a shop you have to take it back to have these things done. Yes they can make more hp, but, this tuner lets us control the way we drive everyday. Thats a plus for me and most of us. Be patient, like the SGR said its coming and I think we will all like it.

Now that I have mine installed, I agree 100% with this post.

SLVRG8GT
03-12-2009, 07:40 PM
Be patient, like the SGR said its coming and I think we will all like it.
I'm trying! :wah:

DRCUSTOMPARTS
03-27-2009, 02:40 PM
Mpostr did you get the results of the Vararam with the Superchips tune yet? I've been wondering how well they work together.

mjf232
04-02-2009, 06:10 PM
Is the tune set up yet for 93 Octane and any CAI?????

DRCUSTOMPARTS
04-02-2009, 06:51 PM
Not yet, they are still trying to get all the CAI's so they can tune them all at once.

ThugHunter
04-02-2009, 07:33 PM
Is the tune set up yet for 93 Octane and any CAI?????

The 93 octane tune has been available for a couple weeks now. The CAI tunes aren't released yet.

mjf232
04-03-2009, 12:21 PM
The 93 octane tune has been available for a couple weeks now. The CAI tunes aren't released yet.

A few more questions:

1. Any eta on the intakes? (I have the ne otr)

2. If I buy one tomorrow will it come tuned for 93 or will I have to download that off of my computer?

3. Will it work on my wifes '05 denali?

SRG963
04-03-2009, 12:22 PM
A few more questions:

1. Any eta on the intakes? (I have the ne otr)

2. If I buy one tomorrow will it come tuned for 93 or will I have to download that off of my computer?

3. Will it work on my wifes '05 denali?

1. Should be soon

2. You will need to update your tuner

3. See http://www.superchips.com/product_reference.php?make=GMC&x=26&y=4 for that info please

mjf232
04-03-2009, 12:25 PM
Also is there still any promotion codes / coupons for it? If so can someone please let me know I am seriously considering this tune option over the others for the reason of simplicity and the mods I have are the otr intake and street series catback. Probably be done with mods after the tune for quite a while.

Out of curiosity, what do you guys think the gains would be with my two mods?

Thanks.

SRG963
04-03-2009, 12:26 PM
Also is there still any promotion codes / coupons for it? If so can someone please let me know I am seriously considering this tune option over the others for the reason of simplicity and the mods I have are the otr intake and street series catback. Probably be done with mods after the tune for quite a while.

Out of curiosity, what do you guys think the gains would be with my two mods?

Thanks.

Maryland Speed has the best deal I believe, $350 shipped.

ThugHunter
04-03-2009, 12:35 PM
Also is there still any promotion codes / coupons for it? If so can someone please let me know I am seriously considering this tune option over the others for the reason of simplicity and the mods I have are the otr intake and street series catback. Probably be done with mods after the tune for quite a while.

Out of curiosity, what do you guys think the gains would be with my two mods?

Thanks.

Maryland Speed has them for $349, which is only $6 more than what I paid with a discount code. They're a site sponsor and satisfied my needs with my axleback. Although it took a little effort as far as phone call follow ups. http://marylandspeed.com/superchips-cortex-tuner-gm-vehicles-2008-pontiac-g8-gt-sup-2950-p-2247.html

Look at my sig for mods and dyno results. I'm not sure what a similar modded car would do with the Vector tune instead of the Superchips tuner, but I'm willing to bet it's not much more if at all. And the convenience of having a handheld tuner in the glove compartment is second to none. The only reason I would consider another tune is if/when I get headers. If Superchips still does not support headers at that time, I will unfortunately have to go with a custom tune and will lose the convenience of the handheld tuner.

DRCUSTOMPARTS
04-03-2009, 12:40 PM
You should gain about 25-30hp with a CAI/catback/tune. You can only tune one vehicle at a time with the Cortex, so you couldn't tune the Denali unless you put yours back to stock.

mjf232
04-05-2009, 07:20 AM
SRG, DRCUSTOMS, and THUGHUNTER, thanks for the replies. I'm gonna order one this week thru Maryland Speed. I got my catback thru them and they were really good to work with. I cant wait till they have the intakes ready for the tune!

SRG963
04-05-2009, 08:22 AM
SRG, DRCUSTOMS, and THUGHUNTER, thanks for the replies. I'm gonna order one this week thru Maryland Speed. I got my catback thru them and they were really good to work with. I cant wait till they have the intakes ready for the tune!

We are all waiting :):watch:

locrzn#92
04-05-2009, 08:50 AM
Yes we are, bring it.

DRCUSTOMPARTS
04-05-2009, 10:31 AM
Years ago you needed some headers, a cam and a high rise intake manifold to get this kind of power. Now we can achieve that with a little electronic device, I love it!

ThugHunter
04-05-2009, 10:37 AM
It just goes to show how detuned cars are coming from the manufacturers.

g8tofast
04-08-2009, 07:11 AM
Is there a ETA on the tuning for the intakes?

DRCUSTOMPARTS
04-08-2009, 07:17 AM
Nope when it's done we'll get it.

SRG963
04-08-2009, 07:24 AM
Is there a ETA on the tuning for the intakes?


Nope when it's done we'll get it.

Just updated my OP :)
http://www.forum.grrrr8.net/showthread.php?p=72152#post72152

PaFromFL
04-08-2009, 09:53 AM
I'm surprised that each brand of CAI requires a separate tune. They all are much less restrictive than stock and draw in unheated air. What makes them so different?

SRG963
04-08-2009, 10:09 AM
I'm surprised that each brand of CAI requires a separate tune. They all are much less restrictive than stock and draw in unheated air. What makes them so different?

I'm sure some of them are more equal than we know.

Placement of the MAF is one big factor when tuning for the different styles.

Superchips wants to ensure the best possible tune for each style, I believe that's why they have ordered almost every kit from every manufacturer.

TCorzett
04-10-2009, 10:33 AM
I have a stock G8GT (but my do a CIA at the same time) and would like to tune for 91 octane (highest I can consistently get in California). I really like the idea of being able to return things to stock for factory servicing.

Reading this thread it seems the tune does some adjustments to the transmission/shift points. Will a 'standard' (something other than me spending hours trying various settings) tune allow me to keep the car from shifting into a higher gear at lower speeds (like being in 5th or 6th gear despite only going 45mph)? Can I have different settings based on being in 'sport mode' or 'standard drive'?

-Todd...

DRCUSTOMPARTS
04-10-2009, 07:23 PM
The trans will shift much better than stock with the Superchips tune, but there's no way you can control what gear the trans will shift to. In sport mode it will hold a gear when going hard into a corner, but for normal driving normal and sport are pretty much the same. There's no way to have separate tunes for the different shift modes, there is one setting for all modes.

109G8GT
02-06-2010, 06:58 AM
My car being away for winter i used my tuner on my friends G8, will flash his bad to stock before i use it on mine. All we can say to the 91 tune is holy crap! Made the car a different beast! Love the hard sideways shifts!

piecesparts
02-06-2010, 07:51 AM
With all of this, anyone have any feedback on mileage numbers (honest). I know the upgrades make oyu drive harder, but the wife is adamant about what she can see for milage.

Is the tune out for the Vararam, yet?

SRG963
02-06-2010, 08:57 AM
With all of this, anyone have any feedback on mileage numbers (honest). I know the upgrades make oyu drive harder, but the wife is adamant about what she can see for milage.

Is the tune out for the Vararam, yet?

Yes, the Vararam CAI tune is available for download.

I have turned off AFM and am still getting as good or better MPG than before. I average over 21 and I was around 20 with the stock tune (W/AFM).

SC is also looking at and will possibly offer a "Fuel Saver" Tune which would extend the AFM and really improve the gas mileage under light throttle. They will be looking into this new tune at the same time they will be revising our TCM tune since they have learned much since the initial release of the G8 tune.

AVIDMOTION
02-06-2010, 12:42 PM
I can't wait for a revised trans tune. However before the x pipe and straight through magnaflows, with a Yella Terra tube, AFE dry panel filter, LP mod, and summer tires with the 91 sc volant tune I got better mpg then stock when not driving it more aggressive. Putting on GY GT(great tire btw) did knock my highway milage down nearly 3 mpg, city was about the same. Adding the X pipe and straight through magnaflows(fairly loud, sounds like a v8, nice gurggle, deep) I got back the highway milage and added 1 more in the city.