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wreckwriter
05-19-2010, 03:10 PM
If I were to pull my whole exhaust system behind the headers (cats, mid-tubes/X pipe and axle-backs) would anything need to be tweaked in the tune?
CanadianEh
05-19-2010, 04:21 PM
I think I have been told before that it wont need to be tuned.. if you tuned it to try and get gains from it you would only get a couple HP
Mike P
05-21-2010, 06:15 AM
If I were to pull my whole exhaust system behind the headers (cats, mid-tubes/X pipe and axle-backs) would anything need to be tweaked in the tune?


Tom:

Call Jeremy (& Dan) to be sure.....

It'd probably be cool just to have Jeremy tune it some more......

Proven Power reminds me of something from "The Fast & the Furious"...... lol :)



...
99-LS1-SS
05-21-2010, 06:19 AM
I doubt you'll have to change much if anything just pulling the exhaust off.
wreckwriter
05-21-2010, 06:24 AM
Tom:

Call Jeremy (& Dan) to be sure.....

It'd probably be cool just to have Jeremy tune it some more......

Proven Power reminds me of something from "The Fast & the Furious"...... lol :)



...

Unfortunately Jeremy doesn't come to WV...........
99-LS1-SS
05-21-2010, 06:29 AM
Are you able to log any without being at the track or getting a ticket (without the exhaust)?
Mike P
05-21-2010, 06:30 AM
Unfortunately Jeremy doesn't come to WV...........


I forgot you moved from Florida to WV..... My bad.....

Road trip it to Gettysburg, PA...... :)

That's not that far at all........ (Not like Michigan to Floriday..... ugh..... :( )



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MGM GT
05-21-2010, 06:42 AM
Your ears will need to be tweaked afterwards. Good grief I drove mine around the block with open headers and literally every door opened because they thought a plane landed in middle of the street.
wreckwriter
05-21-2010, 07:02 AM
Are you able to log any without being at the track or getting a ticket (without the exhaust)?

No
wreckwriter
05-21-2010, 07:04 AM
6 hours to Gettysburg :(
99-LS1-SS
05-21-2010, 07:14 AM
For 6 hours, I would leave it as is....
wreckwriter
05-21-2010, 07:27 AM
I'll see how it runs next race day with timing tweaks. Gonna try to get WB working too.
Patrick G
05-21-2010, 08:35 AM
You're going to need some 18" extensions for your headers if you plan on running O2 sensors and staying in closed loop. With the O2 sensor so close to the edge of the header flange, you will drive your ECM crazy with fuel trim corrections at lower rpm because outside air is going to contaminate the exhaust and give you a false lean reading. Your motor will add fuel to compensate and all your plugs will get fouled out. Not smart.
99-LS1-SS
05-21-2010, 09:01 AM
You're going to need some 18" extensions for your headers if you plan on running O2 sensors and staying in closed loop. With the O2 sensor so close to the edge of the header flange, you will drive your ECM crazy with fuel trim corrections at lower rpm because outside air is going to contaminate the exhaust and give you a false lean reading. Your motor will add fuel to compensate and all your plugs will get fouled out. Not smart.

And this is why Patrick is the Technical advisor and I'm the trial and error noob....

Thanks for clearing this up Patrick.

*Edit
What you said makes perfect sense Patrick. I have a question. Why do you say an 18" extension? I'm just curious.
Patrick G
05-21-2010, 10:22 AM
And this is why Patrick is the Technical advisor and I'm the trial and error noob....

Thanks for clearing this up Patrick.

*Edit
What you said makes perfect sense Patrick. I have a question. Why do you say an 18" extension? I'm just curious.The 18" length seems to be the right size to keep the O2 sensor from getting fouled and to build torque by extending the wave scavenging before the exhaust pulse goes atmospheric.
wreckwriter
05-21-2010, 11:06 AM
OK, guess I'll skip this for now. Thanks for the tip Patrick!
wreckwriter
04-20-2011, 05:22 PM
I'm closed loop without O2 sensors now. I could safely run open headers now, couldn't I?
GRRRR8
04-20-2011, 05:24 PM
Yes. Keep in mind most headers like 12-24 inches of pipe attached to them.
Fatdaddy
04-20-2011, 07:48 PM
Keep in mind most headers like 12-24 inches of pipe attached to them.

I would start with 28 - 32 inch long x 3 inch collectors and shorten them as you test to find the sweet spot. Your advantage in doing this will mostly be seen off the line. The motor should have a little more torque under the curve. Not much change to peak.