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Its Good To Be Tha King
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This thread is intended to share knowledge pertaining to Superchips tunes. This is not a thread to discuss whos tune is better, nor is it a thread in which to confirm using a Superchips tune with long tube headers is safe. If you have used a Superchips tune with long tube headers, please share your experiences and/or misfortunes.


I'll start with some basic info. Adding increased exhaust flow will inherently lean out your cars Air-Fuel Ratio. Superchips 93 Octane tunes call for a higher AFR, approx 12.6~12.8. The 91 and 87 tunes call for 12.3~12.5 I believe.


That being said, I'm currently tuned with the Cortex Rotofab 91 Octane tune. I have a Rotofab CAI and 1 7/8" LT headers (3" X-Pipe, No Cats) installed. Data logging with the Rotofab 91 octane tune has shown my LTFT's at a constant (+3.7) when at partial throttle (not WOT).


The easiest way for you to determine that the specific cai tune is providing you with the most efficient tuning is by loging AFR through our DAQ software in the advanced setting under Fuel Trim Press listed as Sh fuel trim 1 and 2 and Ln fuel trim 1 and 2.

Short term fuel trim, and long term fuel trims while trying the different intake tunes. We request about 12.6~12.8 for afr and he wants his fuel trims as close to 0 as possible (anything under +5 and over -5 is usually considered good).

Scott
 

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Cars are my hobby...
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I ran LTH, catless with the cortex for over a year without any issues. I even raced on them. I never hooked up a WB to see what the AFR was though but my trims were acceptable.
 

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Premium Member
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'scribed.




Thanks for making this.

I want to learn.
 

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I had a Cortex tune set to 93 octane, Vararam intake update, Superchips shift value, shift points raised 200 rpm, top speed limiter removed. My mods are Kooks 1 7/8 long tube headers, no cats, modified mid pipe, Solo axle backs, Vararam intake. I ran the car like this for approx. 4 or 5 months prior to getting the car dyno tuned and raced it plenty of times. No problems were had other then needing new rear tires sooner then I had wanted to have to be buying them. When I went to RPM (Race Proven Motorsports) in Del for my dyno tune they first did a base line pull using the car in its brought in condition, mods as described above. The car made 337 rwhp as for the fuel trims according to the tuner they were fine at idle, went lean just off idle, and then went "fat" for the rest of the rpm band. I asked if in his professional opinion IF the Cortex tuner would have caused me any problems his response was no that it would not have hurt my car to have continued use of the turner. My dyno tune netted 20 rwhp over the Cortex tune.
 

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Cars are my hobby...
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I had a Cortex tune set to 93 octane, Vararam intake update, Superchips shift value, shift points raised 200 rpm, top speed limiter removed. My mods are Kooks 1 7/8 long tube headers, no cats, modified mid pipe, Solo axle backs, Vararam intake. I ran the car like this for approx. 4 or 5 months prior to getting the car dyno tuned and raced it plenty of times. No problems were had other then needing new rear tires sooner then I had wanted to have to be buying them. When I went to RPM (Race Proven Motorsports) in Del for my dyno tune they first did a base line pull using the car in its brought in condition, mods as described above. The car made 337 rwhp as for the fuel trims according to the tuner they were fine at idle, went lean just off idle, and then went "fat" for the rest of the rpm band. I asked if in his professional opinion IF the Cortex tuner would have caused me any problems his response was no that it would not have hurt my car to have continued use of the turner. My dyno tune netted 20 rwhp over the Cortex tune.
I actually dyno'd mine too. Superchips 91, Vararam, Pacesetter LTHs catless, Super 44s and I put down 354rwhp.
 

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Its Good To Be Tha King
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Discussion Starter #7
I know of at least 2 more G8's that haven't chimed in yet....Hello?
 

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Thats how I run mine. Mods in sig below. Oh, and it has the 93 octane Vararam tune loaded from Superchips.
 

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Its Good To Be Tha King
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Discussion Starter #10
Thanks to those that chimed in for the info, especially the members who dyno tested this set-up prior to changing tunes.
 

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Cars are my hobby...
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You're welcome, I wear my flame proof suit at all times on forums. lol
 

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Drives with wolves
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I understand........some have burned those who run Cortex tune and headers :shiner:
 

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I"ve been running it for about a week while I decided on a custom tuner. My only issue is it throwing the 02 senor codes but that is expected.
 

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I"ve been running it for about a week while I decided on a custom tuner. My only issue is it throwing the 02 senor codes but that is expected.
Search anti-fowler 02 sensor mod. This will get rid of the CEL for the 02 sensors.

You're local to me so if you need any help with any of that just PM me. The mod can be done in an hour or so and then just clear the code with Cortex tuner.
 

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Search anti-fowler 02 sensor mod. This will get rid of the CEL for the 02 sensors.

You're local to me so if you need any help with any of that just PM me. The mod can be done in an hour or so and then just clear the code with Cortex tuner.
Why search, it can be summed up in a matter of two pictures:





While this trick has been around for many years, it gained wide-popularity through the Audi B5S4 crowd as mate to gutted cats. This mod moves the sensor out of the exhaust stream, allowing it to read a cleaner mixture than is actually present. To be installed on post-cat (downstream) sensors ONLY.
 

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Thanks for the tip guy's. I'll have new tunes in the next day or so. I should be good then.
 

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^ ^ ^ You only need 1 package of the anti-fowlers. Cutting the shroud/shield off of the sensor tip is much easier then trying to drill out the anti-fowler for the sensor to fit. This is what I did along with stuffing some steel wool inside the anti-fowler before screwing the sensor into it acts as a filter to further cut down on exhaust gasses getting to the sensor.
Before I had my "real" tune done I ran my car this way for 4 or 5 months and never got a CEL once. I never removed them from my car because I figure why bother.
 

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What HP gains did you see by adding the Long tube Headers. Right now I have stock manifolds with cortex and a CAI. I am thinking about headers...but would like to know what kind of HP gains to expect. Also any more interior noise?

Thanks.
 

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What HP gains did you see by adding the Long tube Headers. Right now I have stock manifolds with cortex and a CAI. I am thinking about headers...but would like to know what kind of HP gains to expect. Also any more interior noise?

Thanks.
Sorry man I never dynoed it with the manifolds. The headers deff do make more noise then the manifolds, you an hear the exhaust pulses going thru the headers which sounds like ticking. Also when driving nice and easy and you go up a hill you can really hear the headers, they almost sound like the engine has a miss.
 

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Hoonigan
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I'm sub'd. Just have a Vararam intake for now and planning on doing a Cortex tune with long tubes.
 
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