Testing Exhaust Back Pressure
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Hi,
I will be modifying the exhaust on the LS1 in my '02 C5 soon and would like to document the results in terms of back pressure. Has anybody tested for back pressure before? I am going to use the gauge described below by taping into the exhaust just after the stock manifolds. I will run the pressure line to the interior to allow me to monitor the pressure as I drive.
Chevy info on the '02 LS6 states that the exhaust back pressure was reduced by about 2 in-Hg or about 1 psi. This part of the '02 Z06 mod was worth about 5 hp over the '01 Z06 which has the same system as my '02 LS1. I have also heard that a "good" high performance exhaust system has a back pressure of less then 5 psi. Do you know of any other guidelines?
The exhaust mods I am planning on my '02 Coupe are:
1. Run a pipe through the pre-cats (lower back pressure, more noise)
2. Install an X-pipe (lower BP & dB)
3. Z06 exhaust (lower wt, unknown effect on BP & dB)
Thanks for your help,
Steve
Exhaust Back Pressure Gauge
(SKU# OTC-7215)
Large gauge shows pressure from 0-8 PSI. To use, simply insert into the oxygen sensor hole. Its stainless-steel braided tubing withstands high-heat engine conditions. <img src="graemlins/corvette.gif" border="0" alt="[Corvette]" />
[ December 23, 2001: Message edited by: SNW Vette ]</p>
I will be modifying the exhaust on the LS1 in my '02 C5 soon and would like to document the results in terms of back pressure. Has anybody tested for back pressure before? I am going to use the gauge described below by taping into the exhaust just after the stock manifolds. I will run the pressure line to the interior to allow me to monitor the pressure as I drive.
Chevy info on the '02 LS6 states that the exhaust back pressure was reduced by about 2 in-Hg or about 1 psi. This part of the '02 Z06 mod was worth about 5 hp over the '01 Z06 which has the same system as my '02 LS1. I have also heard that a "good" high performance exhaust system has a back pressure of less then 5 psi. Do you know of any other guidelines?
The exhaust mods I am planning on my '02 Coupe are:
1. Run a pipe through the pre-cats (lower back pressure, more noise)
2. Install an X-pipe (lower BP & dB)
3. Z06 exhaust (lower wt, unknown effect on BP & dB)
Thanks for your help,
Steve
Exhaust Back Pressure Gauge
(SKU# OTC-7215)
Large gauge shows pressure from 0-8 PSI. To use, simply insert into the oxygen sensor hole. Its stainless-steel braided tubing withstands high-heat engine conditions. <img src="graemlins/corvette.gif" border="0" alt="[Corvette]" />
[ December 23, 2001: Message edited by: SNW Vette ]</p>
#2
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Why does everyone try to change what million dollar company's pay people to find out ... Some of you I dont get <img src="images/icons/confused.gif" border="0">
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I have measured the back pressure on my Z.
I used a Dwyer gauge, I will look up the model number when I get home. Get a good gauge.
My test results are on my website. Go to the Library link or click on the link in the latest news and notes.
Shoot me an email and I can tell you how I taped the pipe. Onfire got me interested in this a while back.
ERic
www.installuniversity.com
I used a Dwyer gauge, I will look up the model number when I get home. Get a good gauge.
My test results are on my website. Go to the Library link or click on the link in the latest news and notes.
Shoot me an email and I can tell you how I taped the pipe. Onfire got me interested in this a while back.
ERic
www.installuniversity.com
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Damn do I feel sorry for those of you worried about back pressure...you must live so far away from a track that you can't afford the gas/time it takes to get there! I apologize on behalf of track owners everywhere! We should build a track in your back yard, that way you would see how much people at "(your name here)'s raceway" were concerned with back pressure!
While adding back pressure, you might want to add a huge restriction in your intake, gotta get "front" pressure to even out that power giving back pressure!
It's all about tuning...run open headers with the right tuning, "Damn, this thing will kick the **** out of my mustang!" This will be all you'll hear from your passengers!
And if your going to give the argument, well you lose lowend...So f'ing what!!! You more than makeup with topend.
While adding back pressure, you might want to add a huge restriction in your intake, gotta get "front" pressure to even out that power giving back pressure!
It's all about tuning...run open headers with the right tuning, "Damn, this thing will kick the **** out of my mustang!" This will be all you'll hear from your passengers!
And if your going to give the argument, well you lose lowend...So f'ing what!!! You more than makeup with topend.
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They're not adding backpressure Jacobi....they are documenting a baseline and making changes to REDUCE backpressure...go to Wizkid's webpage for some good info...David Vizard's book has some great reference data on BP.
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WizKid, thanks for the info. I'll send you the C5 data when I get it. I would appreciate the info on your installation so I'll send you an e-mail.
OnFire, thanks for the general explanation, I didn't think this was Rocket Science. Vizard's book is were I read that under 5 psi was the start of "good" systems. I am trying to build-up an exhaust that supports a higher overlap cam but won't make the car too loud.
Thank,
Steve
OnFire, thanks for the general explanation, I didn't think this was Rocket Science. Vizard's book is were I read that under 5 psi was the start of "good" systems. I am trying to build-up an exhaust that supports a higher overlap cam but won't make the car too loud.
Thank,
Steve
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[quote]Originally posted by onfire:
<strong>They're not adding backpressure Jacobi....they are documenting a baseline and making changes to REDUCE backpressure...go to Wizkid's webpage for some good info...David Vizard's book has some great reference data on BP.</strong><hr></blockquote>
Sorry, been a long day!
<strong>They're not adding backpressure Jacobi....they are documenting a baseline and making changes to REDUCE backpressure...go to Wizkid's webpage for some good info...David Vizard's book has some great reference data on BP.</strong><hr></blockquote>
Sorry, been a long day!
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you have mail <img src="gr_stretch.gif" border="0">
Get'em Tom. <img src="gr_images/icons/wink.gif" border="0"> hahahah j/k everyone.
Eric
Get'em Tom. <img src="gr_images/icons/wink.gif" border="0"> hahahah j/k everyone.
Eric