[Z06] LT Headers- Reasonable HP Expectations?
Pro
Joined: Jul 2008
Posts: 647
Likes: 5
In Houston you get a fine for not running cats- I know people who've been pulled over and the LEO checked underneath for cats. Serious fine I think.
Regardless- the cats are there to reduce the pollution my kids are going to have to deal for years to come. I'm sticking with them
Regardless- the cats are there to reduce the pollution my kids are going to have to deal for years to come. I'm sticking with them
Drifting
Joined: Oct 2009
Posts: 1,438
Likes: 4
From: Always in my lane.
That may be Mr. Officer. But Ive had them on for 5 yrs. and it passes the emission tests so I can renew my plates. I doubt that would be the case if I ran straight pipes. ( I also pass visual inspection).
Thread Starter
Burning Brakes
Joined: Aug 2007
Posts: 831
Likes: 2
From: Houston Texas
Why not set a good example for the younger folks by staying within the law.
Besides, removing the cats only add negligible HP. Is it really worth the risk- and more importantly is it worth polluting the environment ?
My view , Hot rodding is all about playing within the rules to extract the most hp/fun. Breaking laws for 2 HP (or 20 HP) makes no sense at all.
In Texas - it's against the law to remove the cats. That's good enough for me
Besides, removing the cats only add negligible HP. Is it really worth the risk- and more importantly is it worth polluting the environment ?
My view , Hot rodding is all about playing within the rules to extract the most hp/fun. Breaking laws for 2 HP (or 20 HP) makes no sense at all.
In Texas - it's against the law to remove the cats. That's good enough for me
Thread Starter
Burning Brakes
Joined: Aug 2007
Posts: 831
Likes: 2
From: Houston Texas
Those are great numbers ! My 2002 Z06 after tune was 374RWHP with homemade CAI and NO headers. This is what spurred my original post - trying to figure out what LT Headers would get me.
In my case- hopefully LT Headers will get me at least 390RWHP to justify the cost.
In my case- hopefully LT Headers will get me at least 390RWHP to justify the cost.
Last edited by NatB; Nov 1, 2009 at 10:57 PM.
Le Mans Master
Joined: Dec 2007
Posts: 8,375
Likes: 97
From: Somewhere in the Mid 9's TX
track times are what counts, I picked up 4mph with the vararam and LT's. Plus, you need the headers when you add more mods to the car.
Drifting
Joined: Sep 2008
Posts: 1,273
Likes: 9
From: O'Fallon MO
Cost is 1 reason not to have them, and sound would be another. Some people like their car to be loud, and no cats is a way to make it a bit louder. Now if a slight increase in power comes as an addition to those goals then the more the merrier.
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Safety Car
Joined: Jan 2007
Posts: 4,225
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From: The Great Truth: "There ain't no free lunch"
St. Jude Donor '08-'09-'10-'11
Nice strong engine ya got there....congratulations......I would be dissapointed with less than 20 HP, but it could happen........Lots of headers options out there....longer tube produce more torque at lower RPM, shorter at high RPM....are your goals DYNO racing, track or just driving?
Thread Starter
Burning Brakes
Joined: Aug 2007
Posts: 831
Likes: 2
From: Houston Texas
Nice strong engine ya got there....congratulations......I would be dissapointed with less than 20 HP, but it could happen........Lots of headers options out there....longer tube produce more torque at lower RPM, shorter at high RPM....are your goals DYNO racing, track or just driving?
Aside from performance - I am also looking for a little more aggressive exhaust to supplement my Corsa Extremes
Le Mans Master
Joined: Dec 2001
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From: Winchester TN
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St. Jude Donor '03-'04-'05-'06-'07-'11
Thanks ! I am looking for low end street torque- performance I can feel driving around town. I don't intend to track the car- it's a driver. Seems like most steer towards either the LG Pros or the American Racing. From all I've read- they are both great products with I suppose similar performance gains.
Aside from performance - I am also looking for a little more aggressive exhaust to supplement my Corsa Extremes
Aside from performance - I am also looking for a little more aggressive exhaust to supplement my Corsa Extremes
You can expect around 15 hp with cat delete - a little less if you decide to leave the cats on.
The thing is, if you do a cold air intake and a tune, you'll get a certain amount from the tune that is not included in the 15 I quote above.
For the record - my 02 Z did 356 rwhp bone stock, and 374 after CAI and a tune by Breathless (Ernie Francis).
Then, when I later did the LG Pros with cat delete, the car did 389.
Sean from LG did not have to change the tune much after the header install.
Just for fun - a vid of my 02 Z with LG pros, cat delete, cold air intake and tune. I also have a BPP billet shifter.
http://www.youtube.com/watch?v=iRMfgNO541w
best regards -
mqqn
Thread Starter
Burning Brakes
Joined: Aug 2007
Posts: 831
Likes: 2
From: Houston Texas
Hi NatB -
You can expect around 15 hp with cat delete - a little less if you decide to leave the cats on.
The thing is, if you do a cold air intake and a tune, you'll get a certain amount from the tune that is not included in the 15 I quote above.
For the record - my 02 Z did 356 rwhp bone stock, and 374 after CAI and a tune by Breathless (Ernie Francis).
Then, when I later did the LG Pros with cat delete, the car did 389.
Sean from LG did not have to change the tune much after the header install.
Just for fun - a vid of my 02 Z with LG pros, cat delete, cold air intake and tune. I also have a BPP billet shifter.
http://www.youtube.com/watch?v=iRMfgNO541w
best regards -
mqqn
You can expect around 15 hp with cat delete - a little less if you decide to leave the cats on.
The thing is, if you do a cold air intake and a tune, you'll get a certain amount from the tune that is not included in the 15 I quote above.
For the record - my 02 Z did 356 rwhp bone stock, and 374 after CAI and a tune by Breathless (Ernie Francis).
Then, when I later did the LG Pros with cat delete, the car did 389.
Sean from LG did not have to change the tune much after the header install.
Just for fun - a vid of my 02 Z with LG pros, cat delete, cold air intake and tune. I also have a BPP billet shifter.
http://www.youtube.com/watch?v=iRMfgNO541w
best regards -
mqqn
I agree the the addition of LT headers after tuning with the CAI would likely not add the 20-30 RWHP people talk about. Seems like that number would be more achievable going from bone stock to LT headers and a CAI.
It's interesting that my DIY CAI (based on excellent directions on this site) seems to yield nearly as much HP as the super expensive engineered CAI's (please no angry debates). I wonder if the Honker would have yielded any more HP? My guess - marginally perhaps 1-2 HP at most over my DIY rig.
Le Mans Master
Joined: Dec 2001
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From: Winchester TN
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St. Jude Donor '03-'04-'05-'06-'07-'11
Thanks ! My 2002 Z06 with homemade CAI and cat-back pulled 368RWHP before being tuned - after EnglandGreen tuned it it pulled about 374RWHP. Right on with your numbers before headers.
I agree the the addition of LT headers after tuning with the CAI would likely not add the 20-30 RWHP people talk about. Seems like that number would be more achievable going from bone stock to LT headers and a CAI.
It's interesting that my DIY CAI (based on excellent directions on this site) seems to yield nearly as much HP as the super expensive engineered CAI's (please no angry debates). I wonder if the Honker would have yielded any more HP? My guess - marginally perhaps 1-2 HP at most over my DIY rig.
I agree the the addition of LT headers after tuning with the CAI would likely not add the 20-30 RWHP people talk about. Seems like that number would be more achievable going from bone stock to LT headers and a CAI.
It's interesting that my DIY CAI (based on excellent directions on this site) seems to yield nearly as much HP as the super expensive engineered CAI's (please no angry debates). I wonder if the Honker would have yielded any more HP? My guess - marginally perhaps 1-2 HP at most over my DIY rig.
People here have their allegiances to once CAI or another, but the basic truth is that if you can open up the intake to exceed the ability of the maf, then you have done all you can do. From there it is simply the colder the air the better.
If I remember correctly the stock maf can flow around 360cfm.
I like your method - cheap and effective!
best regards -
mqqn
Drifting
Joined: Sep 2008
Posts: 1,273
Likes: 9
From: O'Fallon MO
Thanks ! I am looking for low end street torque- performance I can feel driving around town. I don't intend to track the car- it's a driver. Seems like most steer towards either the LG Pros or the American Racing. From all I've read- they are both great products with I suppose similar performance gains.
Aside from performance - I am also looking for a little more aggressive exhaust to supplement my Corsa Extremes
Aside from performance - I am also looking for a little more aggressive exhaust to supplement my Corsa Extremes
I got 1 3/4 with uncated x-pipe, coated by Jet Hot, all for right at $1,315.00 to my door.
I wish I had some #'s for you after my install but it has yet to get back on the dyno.
Le Mans Master
Joined: Dec 2007
Posts: 8,375
Likes: 97
From: Somewhere in the Mid 9's TX
I agree, kooks are great, but I trap 117 with just Texas Speed coated headers and CAI for a little more than half of your price.
Burning Brakes
Joined: Aug 2007
Posts: 880
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From: Bath PA
That was the point. There was no difference in HP. Cost diff is negligible in the grand scheme. Car remains emissions legal and the only way to tell the difference in sound is with a decibel meter. But it's your car, and BTW I believe it's a federal law about removing cats not state. Some states simply choose to actively inspect/enforce while others don't.
Pro
Joined: Jul 2008
Posts: 647
Likes: 5
High flow cats are also bad for the environment. I do plenty of things for the environment. I recycle..My entire home is enery bulbs...exc...I only drive this car on the weekends and its more powerful and sounds better. I also pass inspection. I cant remember the last time they did a visual inspection for cats on any of my vehicles
Drifting
Joined: Oct 2009
Posts: 1,438
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From: Always in my lane.
I repeat Mr. Officer. In my area, visual inspections are done at the emission stations so it doesnt make any sense for me to risk fines and penalties, license plate and drivers license suspensions, the hassel of having to get the exhaust system squared away , dealing with the DMV after its all said and done, just to run straight pipes. Every jurisdiction handles emission tests differently. If I ran straight pipes its probably good for a couple extra horses over what I have now. To each his own.
Pro
Joined: Jul 2008
Posts: 647
Likes: 5
I repeat Mr. Officer. In my area, visual inspections are done at the emission stations so it doesnt make any sense for me to risk fines and penalties, license plate and drivers license suspensions, the hassel of having to get the exhaust system squared away , dealing with the DMV after its all said and done, just to run straight pipes. Every jurisdiction handles emission tests differently. If I ran straight pipes its probably good for a couple extra horses over what I have now. To each his own.
Supporting Tuner
Joined: Sep 2004
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From: ================== Houston, Texas www.englandgreen.com ================== Necessary Evil™ __________
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
