Choosing The Right Long Tube Headers

[White_SS/RS]

Originally Posted by scoticus.rex

Just installed a set of Kook's Longtube Headers and green high performance cats on Hobbes. I have them installed at Broadview Auto Services in Warranton, Virginia. Here are a couple of pics of the install and a link to the dynotune video as well. Can't figure out how to embed a video directly.



Here is a video I took while John was dyno tuning Hobbes after the Kooks install. Topped out at 434 RWHP with a conservative street tune.

http://youtu.be/7x425EeNiH8

What clamps are you using between the header and cats? Looks clean!

[scoticus.rex]

No idea on the clamps. I had Broadview Auto Services in Warrenton, Virginia do the install. The clamps either came with the headers, were stock or were provided by them.

[rockrau]

Aren't they the new KOOKS style?

[Ryanbabz71]

Are you talking about the gold clamps in the photo? Those are stock clamps. I have those on mine and reused to connect to my stainless power headers


Ryan

[Ryanbabz71]

Got my stainless power 1-7/8" headers with cats on

https://m.youtube.com/watch?v=eRr1p0...ature=youtu.be

Has flowmaster axle back also

Just a startup video for now


Ryan

[rockrau]

I'm considering between ARH 1 7/8 long system(like the 3" X pipe) and KOOKS 1 7/8 (also considering stepped). Since I use my car on the street and road course and is 1 3/4" lower than stock, ground clearance is an issue. I have scraped the uni-body frame rails several times so the cats cannot hang below them! From some posts & pictures I have seen the KOOKS tuck up close under car. How do the ARH compare? Any advice or opinions would be helpful.

[L99CAMA2011]

Originally Posted by White_SS/RS

What clamps are you using between the header and cats? Looks clean!

Kooks uses the ball flange setup that doesn't leak at all. The coating is a great idea. I need Kooks cats like these. rockrau Both Kooks and ARH tuck up very well.

[scoticus.rex]

Originally Posted by L99CAMA2011

Kooks uses the ball flange setup that doesn't leak at all. The coating is a great idea. I need Kooks cats like these. rockrau Both Kooks and ARH tuck up very well.

I went with the Kooks Hi Performance Green Cats for my setup. They were very highly rates, appear to actually generate better gains than the standard Kooks Hi Performance Cats, and are 49 state emissions legal which is important when you are in the military and occasionally move from state to state.

[L99CAMA2011]

Originally Posted by scoticus.rex

I went with the Kooks Hi Performance Green Cats for my setup. They were very highly rates, appear to actually generate better gains than the standard Kooks Hi Performance Cats, and are 49 state emissions legal which is important when you are in the military and occasionally move from state to state.

Stock cats are 400 cell count, regular hi flos are 200 cell count, green cats as told to me my Kooks tech are 300 cell count and don't flow as well as catless or hi flo. I am wondering if that better gain is from the bit of added restriction over catless or hi flo but not as restrictive as stock. Hmmm.

[pir4te]

Originally Posted by Apex Motorsports

You will see no measurable difference going to the x-pipe. Moving the step down farther to the rear of the car will make no difference at all. No matter where it is it is still there. You would have to have a serious forced induction set up flowing a whole lot of air before anything you do behind the cats is really going to do much for you though.

So reflected acoustic waves, specifically at the second harmonic actually has no effect on scavenging at lower RPM?!
Wow, discovered a breakthrough for world Motorsport mate! Better tell Vizard and Meaux (PipeMax). So what you are declaring is the millions of dollars and dozens of whitepapers by academics and research ratified by SAE international is false, and you believe that there is no energy release when you split the double pulse from a dual plane crank, and even at the correct calculated length to reflect back into chamber at the second (or third) harmonic that sonic waves have no measurable effect on clearing spent gas?
Seemed to work for the world so far, pray tell how tuning of sonic / supersonic waves has no effect (x-pipes, don't work), and cutting edge header / exhaust design is all about flow (CFM).

[Mgizzle]

Originally Posted by Ryanbabz71

Got my stainless power 1-7/8" headers with cats on

https://m.youtube.com/watch?v=eRr1p0...ature=youtu.be

Has flowmaster axle back also

Just a startup video for now


Ryan

Hey Ryan, could you please do me a favor and take a few pictures of the clearance to the steering shaft from the stainless headers? I would appreciate a few pictures please with something in reference or a measure of how much clearance there is. My biggest worry with these headers is the steering shaft clearance and not having any thermal insulation to it. Anybody have pictures of other headers and how they clear the steering shaft? Would appreciate it!!By the way, anybody know who else might sell Tri-Y headers since the Pfadt ones are pretty much impossible to get anymore?

[Ryanbabz71]

I will see what I can do. I did not have to disconnect the steering shaft install if that helps also didn't notice any rub.


Ryan

[Apex Motorsports]

Originally Posted by pir4te

So reflected acoustic waves, specifically at the second harmonic actually has no effect on scavenging at lower RPM?!
Wow, discovered a breakthrough for world Motorsport mate! Better tell Vizard and Meaux (PipeMax). So what you are declaring is the millions of dollars and dozens of whitepapers by academics and research ratified by SAE international is false, and you believe that there is no energy release when you split the double pulse from a dual plane crank, and even at the correct calculated length to reflect back into chamber at the second (or third) harmonic that sonic waves have no measurable effect on clearing spent gas?
Seemed to work for the world so far, pray tell how tuning of sonic / supersonic waves has no effect (x-pipes, don't work), and cutting edge header / exhaust design is all about flow (CFM).

Context is everything. In general, yes, x-pipes do produce gains over an H-pipe. But after working with the 5th Gen Camaro for over 5 years now we have never seen an x-pipe alone produce gains measurable on a dyno over the stock H-pipe. It is kind of a fluke that it doesn't but it is what it is. And the step down being discussed was not in the context of a properly engineered stepped header that is designed to assist in exhaust scavenging. He was asking about restriction if he reduced his cat back pipe diameter at one location versus another. Yes, there is probably a sweet spot you could put it in to pull out a few more horsepower but that is not what he was asking about or even looking to do. It was a naturally aspirated street car, not a max effort build. He had two bolt together locations he was consider. No careful measurement and testing or fabrication.

[Apex Motorsports]

Originally Posted by Mgizzle

By the way, anybody know who else might sell Tri-Y headers since the Pfadt ones are pretty much impossible to get anymore?

No one else makes a set worth getting but the Pfadt Tri-Ys will be available again soon.