Arh headers vs kooks....real results...
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Arh headers vs kooks....real results...
Finally started modding my stingray last week after putting 900 miles on the car. Started with a set of kooks lt headers with cats last week. After all the threads about this vs that headers tests i decided to buY a set of the arh mod lengths and had them installed as well......interesting results....this was a straight up test same day with a stock engine tune. to say the least I was quite surprised of the difference between them.
on the street its like a whole different car. Can't wait to get the cam stuffed in it next!
on the street its like a whole different car. Can't wait to get the cam stuffed in it next!
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From: salem OR
Finally started modding my stingray last week after putting 900 miles on the car. Started with a set of kooks lt headers with cats last week. After all the threads about this vs that headers tests i decided to buY a set of the arh mod lengths and had them installed as well......interesting results....this was a straight up test same day with a stock engine tune. to say the least I was quite surprised of the difference between them.
on the street its like a whole different car. Can't wait to get the cam stuffed in it next!
on the street its like a whole different car. Can't wait to get the cam stuffed in it next!
Le Mans Master
Joined: Jan 2005
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From: Lake Wylie SC
This is where not needing a tune might reflect a header that does not perform as well as the one (Kooks) needing a tune. On the other hand the one not neeing the tune (ARH) may be the ticket for the owner who does not want to risk messing up their warranty
Kudos to the OP for doing the test
Kudos to the OP for doing the test
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Interesting results. Just wonder what the story would be with a tune on both sets if headers?
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Le Mans Master
Joined: Dec 2005
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From: Port Arthur, Texas 77642
Interesting results, thanks for putting out the money to test. I'm not a header engineer or designer but I would guess that a mid length header would not be as far as a departure from factory "flow and pulses" and within parameters of PCM to adjust for optimal results. Whereas, possibly both ARH or Kooks LT'S would yield similar results and both perform best with a tune to optimize.
I would love to hear Kooks input to this thread. I think if it were 2 sets of LT's compared you would see similar results. There is a reason ARH manufactured mid length headers and I'm certain it was not to be an "average performer". I think they were designed to be used without a tune to capture market segment that would not want to install custom tune and void warranty. If a breakage occurs you can always reinstall factory exhaust before returning to dealership.
I would love to hear Kooks input to this thread. I think if it were 2 sets of LT's compared you would see similar results. There is a reason ARH manufactured mid length headers and I'm certain it was not to be an "average performer". I think they were designed to be used without a tune to capture market segment that would not want to install custom tune and void warranty. If a breakage occurs you can always reinstall factory exhaust before returning to dealership.
Le Mans Master
Joined: Dec 2005
Posts: 8,475
Likes: 332
From: Port Arthur, Texas 77642
Finally started modding my stingray last week after putting 900 miles on the car. Started with a set of kooks lt headers with cats last week. After all the threads about this vs that headers tests i decided to buY a set of the arh mod lengths and had them installed as well......interesting results....this was a straight up test same day with a stock engine tune. to say the least I was quite surprised of the difference between them.
on the street its like a whole different car. Can't wait to get the cam stuffed in it next!
on the street its like a whole different car. Can't wait to get the cam stuffed in it next!
Le Mans Master
Joined: Dec 2005
Posts: 8,475
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From: Port Arthur, Texas 77642
Reference this post for tuned vs. untuned on ARH LT's
Link below to post by CF forum vendor comparing results of ARH LT's un-tuned vs. tuned. I think you would see similar results with Kooks LT's tuned. Both Kooks and ARH are top shelf products and I'm not a fan-boy of either. Your comparison validates to some degree that a mid length (by ARH or Kooks if they made them) will yield superior results un-tuned. Likely Kooks and other header manufacturers will jump on the bandwagon if mid lengths prove to perform without custom tune.
On your test of the ARH and Kooks, did either set trigger your check engine light? Did the Kooks have their new "Green Cats"?
http://forums.corvetteforum.com/c7-t...r-results.html
On your test of the ARH and Kooks, did either set trigger your check engine light? Did the Kooks have their new "Green Cats"?
http://forums.corvetteforum.com/c7-t...r-results.html
Le Mans Master
Joined: Jan 2005
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From: Lake Wylie SC
@NemesisC5
You have three in a row good posts here
I will add that while smaller diameter runners (and collectors) will produce more torque on the same given airflow, when airflow is increased (HP motor mods by nature are all designed to increase airflow) will benefit the larger diameter headers over the smaller diameter headers (keeping things in reason such as no open shorty pipes that would result in burnt out valves when used outside the dragstrip) over those with smaller diameters (and why some header companies include "steps" in their design).
As you have pointed out it is critically important to stick to an "apples to apples" comparison
You have three in a row good posts here
I will add that while smaller diameter runners (and collectors) will produce more torque on the same given airflow, when airflow is increased (HP motor mods by nature are all designed to increase airflow) will benefit the larger diameter headers over the smaller diameter headers (keeping things in reason such as no open shorty pipes that would result in burnt out valves when used outside the dragstrip) over those with smaller diameters (and why some header companies include "steps" in their design).
As you have pointed out it is critically important to stick to an "apples to apples" comparison
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Joined: Nov 2005
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From: Amityville ny 631-608-1986
Guys our Mid Lengths were developed to produce excellent HP and Torque gains untuned and that's exactly what they do. Keep in mind that the power gains observed by the OP where with 4 catalytic converters, not two. Anyone can tune our Mids for increased power. I also expectt they'd do really well with a cam swap.
Like our Mids, a lot of thought went into our long tubes and it's become very clear that they also work extremely well. What we were thrilled about during the prototype process was that the chassis allowed us to build headers with optimized primary lengths. Combined with our other features, our Long Tubes and Mid Lengths perform exactly as they were intended to with room to spare.
I welcome anyone to contact me directly to discuss in detail what your C7 plans are. Thanks
Nick
A.R. Headers
Like our Mids, a lot of thought went into our long tubes and it's become very clear that they also work extremely well. What we were thrilled about during the prototype process was that the chassis allowed us to build headers with optimized primary lengths. Combined with our other features, our Long Tubes and Mid Lengths perform exactly as they were intended to with room to spare.
I welcome anyone to contact me directly to discuss in detail what your C7 plans are. Thanks
Nick
A.R. Headers
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Joined: Dec 1999
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From: Texas Speed TX
I'd love to reproduce this test on the engine dyno! In that arena we can track airflow usage, oil temps, etc... It helps to show the differences in many different areas and also helps to confirm everything is the same.
Le Mans Master
Joined: Dec 2005
Posts: 8,475
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From: Port Arthur, Texas 77642
Guys our Mid Lengths were developed to produce excellent HP and Torque gains untuned and that's exactly what they do. Keep in mind that the power gains observed by the OP where with 4 catalytic converters, not two. Anyone can tune our Mids for increased power. I also expectt they'd do really well with a cam swap.
Like our Mids, a lot of thought went into our long tubes and it's become very clear that they also work extremely well. What we were thrilled about during the prototype process was that the chassis allowed us to build headers with optimized primary lengths. Combined with our other features, our Long Tubes and Mid Lengths perform exactly as they were intended to with room to spare.
I welcome anyone to contact me directly to discuss in detail what your C7 plans are. Thanks
Nick
A.R. Headers
Like our Mids, a lot of thought went into our long tubes and it's become very clear that they also work extremely well. What we were thrilled about during the prototype process was that the chassis allowed us to build headers with optimized primary lengths. Combined with our other features, our Long Tubes and Mid Lengths perform exactly as they were intended to with room to spare.
I welcome anyone to contact me directly to discuss in detail what your C7 plans are. Thanks
Nick
A.R. Headers
Nick, can you post a picture of your Mid Lengths? Do they connect to factory exhaust through factory cats or do they also come with/without cats and require an X-pipe? We all know how "shorties" bolt in place of factory manifolds but personally I've never seen a Mid Length setup for any Corvette.
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From: Gilbert AZ
Premium Supporting Vendor
Joined: Nov 2005
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From: Amityville ny 631-608-1986
I think the entire forum is pretty much behind you this now!
I agree, this is very strange. It practically dyno'd lower with the kooks longtube headers installed than most typical C7's dyno stock. As far as I can remember, long tube headers always have made more power than shorties. The LT1 is a new motor, but that doesn't mean it runs on voodoo. The kooks have already been proven to make some of the best power on the C7, but in this particular "test", they seemingly caused a power loss to the C7?? Other posts have been proving the Kooks to be the best big horsepower headers out there. There have been a lot of "interesting" posts surrounding ARH headers lately. Hopefully the Texas Speed test clears the air a little
I agree, this is very strange. It practically dyno'd lower with the kooks longtube headers installed than most typical C7's dyno stock. As far as I can remember, long tube headers always have made more power than shorties. The LT1 is a new motor, but that doesn't mean it runs on voodoo. The kooks have already been proven to make some of the best power on the C7, but in this particular "test", they seemingly caused a power loss to the C7?? Other posts have been proving the Kooks to be the best big horsepower headers out there. There have been a lot of "interesting" posts surrounding ARH headers lately. Hopefully the Texas Speed test clears the air a little
Not sure how you've come to that assessment but our long tubes outperform our Mids and our Mids clearly do a great job while breathing thru 4 catalytic converters. I also welcome anyone to take a good look at our primary length compared to the headers we were up against in this test. You may notice our Mids are pretty darn close in length yet we still call them Mid Lengths. ARH long tubes are considerably longer than our Mids at 30".
Nick
Premium Supporting Vendor
Joined: Nov 2005
Posts: 1,779
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From: Amityville ny 631-608-1986
From independent results on the forums and in person, I've seen the Kooks make amazing power. Now fast forward and we have this cheesy dyno picture with no base line pulls, no additional info, no pictures, no video....really nothing to give us any context at all for how/what was tested.To make things better, it attempts to convince us that the "mid-length" headers will make more power?? Sign me up, can i give my SS # with my CC while I'm at it? 
Nick
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From: Cumming Georgia
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Last edited by Ron@Vengeance Racing; Nov 24, 2013 at 09:00 PM.