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Headers - ARH vs. KOOKS

7K views 17 replies 6 participants last post by  Grabber05 
#1 ·
So I'm planing my build for down the road, not ready just yet. I plan to use a local speed shop for the wrenching (I can't do it anymore). The owner/Dyno-Tuner there is a KOOKS dealer so he pushes the KOOKS and sells them cheaper than any place else I've found.

I like the looks of these ARH headers and I've read a few posts indicating they're easier to tune for with regards to O2 sensors on the Catted-H setup.

Opinions?
 
#2 ·
I have the Kooks and I am happy with them. Have you checked out the Maryland Speed pricing? When I was shopping around they had the best prices.

I don't know much about ARH. I believe they are a good brand. I would recommend researching to see if they have the same type of SS that Kooks uses and if the thickness/gauge is equivalent or better than Kooks. I know I have a file somewhere where I did some extensive research and ended up going with Kooks even though they are not a true long tube header and considered midlength headers.
 
#3 ·
They are the same grade SS, but I don't what gauge thickness. Yeah, I've looked at Maryland Speed. I can get them about $200 cheaper, but I'm not really so concerned about a couple hundred bucks. I just don't want to have CEL/O2 issues. I'm pretty sure ARH build quality matches the KOOKS, but of course I don't KNOW that to be a fact. I'd just love me to know the pros & cons if there are any.
 
#4 ·
They are the same grade SS, but I don't what gauge thickness. Yeah, I've looked at Maryland Speed. I can get them about $200 cheaper, but I'm not really so concerned about a couple hundred bucks. I just don't want to have CEL/O2 issues. I'm pretty sure ARH build quality matches the KOOKS, but of course I don't KNOW that to be a fact. I'd just love me to know the pros & cons if there are any.
 
#5 ·
From what I have read (not direct experience) the Kooks have about the best fit and finish of all the headers out there, so the least likely to have any clearance issues on install. That would be pretty important to me.

To avoid the O2 / CEL issues, you need to use the Kooks "green" cats, or so I am told. They are about $350 more over the "regular" cats.
 
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#6 ·
JBert is likely correct about needing the green cats. I have the regular Kooks cats and I was getting CEL's and had to have the tune eliminate the particular CEL codes that I was getting. There are no emissions testing in my area.
 
#9 ·
Well, I "THINK" tuning would be required regardless to avoid the CEL issues and I'm okay with that. I just don't want to HAVE to turn off the rear O2s because the thing is so far out of spec. it's the only way to make the light go off (if that's possible). I could be chasing my tail here, but that's what the thread is for... To learn...
 
#10 ·
Yeah, I saw that a while back. It makes me wonder how any header can make more power, since the 5.0L has a shorty in stock form.
 
#8 ·
It sounds like I may as well go with the KOOKS. I guess there's a reason they're the most popular. It's just that the ARH look like long tube headers, and are designed with a wide spread which makes transmission removal/install easy. I'm sure I'll need a clutch down the road. Plus the ARH just looks more like a header (I know, silly... Who cares).

So I guess I'll just let my shop go with the KOOKS, probably less hassles for everyone. I didn't know about the "Green Cats" so that's good to know. I'll discuss it with him when the time comes.

Thanks for the input...
 
#11 ·
Kooks has had some quality problems of late- seen a few headers with gaps in the collector where the primaries are supposed to be welded together. PITA but Kooks took care of it right away. YMMV.
 
#12 ·
Since the speed shop I plan to use for the install stocks them at all times, that's probably not a concern. All they do are Mustangs so I'm guessing it'll be a pretty quick install/tune when I make the move.
 
#13 ·
I'm pretty sure you always need to tune for headers to get the best performance.

As I understand it, the issue with the CEL / emissions / O2's is that most "high flow" cats don't work very well, so the rear O2's register that they are not working and then the rear O2 has to be turned off to avoid that code / CEL. But that's a catch-22 because you cannot pass emissions with the O2's turned off, all sensors must be reading "ready"
 
#14 ·
Yeah, that was my worry since we have OBDII/emissions testing here. I talked with the tuner today, and he assures me that the car will pass all testing after the install. Hopefully he's a straight shooter here. He's not pushing a sale, and busier than a 3 legged man in a butt kicking contest.

https://www.facebook.com/ProDynoSC

Well, I guess I'll have to trust this and if it doesn't work out so be it.
 
#15 ·
I went with Kooks 1-3/4" LT's and a Kooks O/R H-pipe. The guy that did the install has done a tone of work on 5.0's and has found that Kooks are usually a direct fit 99% of the time. However, he has had to re-weld 02 sensor locations on ARH's before, but, never on a pair of Kooks.

My car went from 422 RWHP / 367 RWTQ with a Lethal O/R H and axle-backs to 443 RWHP / 388 RWTQ with Kooks 1-3/4" LT's and an O/R H with a revised tune.

Power and sound is there.

I vote Kooks
 
#16 ·
Thanks for replying, I've pretty much decided it's going to be Kooks. Seems like it's great quality and less trouble all around.
 
#17 ·
Very interesting as you certainly have gotten great dyno results. A lot of it appears to be due to using a ported cobra jet manifold, special throttle body, and an AED tune. I assume you used a dynojet dyno.

I have the same headers with the cats, stock manifold, and Bama tunes and can only manage about 380 hp. I have the kooks catless pipes purchased already but I think my car would get way to loud since it is pretty loud right now. I am tempted to find out what it sounds like and what my gains might be. And after that I am strongly considering an AED tune but not sure if he can tune with Diablosport tuner.
 
#18 ·
Very interesting as you certainly have gotten great dyno results. A lot of it appears to be due to using a ported cobra jet manifold, special throttle body, and an AED tune. I assume you used a dynojet dyno.



I have the same headers with the cats, stock manifold, and Bama tunes and can only manage about 380 hp. I have the kooks catless pipes purchased already but I think my car would get way to loud since it is pretty loud right now. I am tempted to find out what it sounds like and what my gains might be. And after that I am strongly considering an AED tune but not sure if he can tune with Diablosport tuner.

Hey,

When my car had stock headers I already had the ported CJ Manifold, TB, intake, O/R H and axle backs.

The newer numbers were headers only and swapping to a different O/R H.

It was done on a Dynocom which is the same dyno AED uses which is extremely accurate.

I had some knock in mid-upper range. I'm hoping to go back with 100 Octane or higher and shoot for 450+ RWHP.

I respect Bama as a business, but, they have nowhere near the knowledge of 5.0's as Lund or AED. Everyone I've seen switch from Bama made more power and the car felt a lot stronger and drove better. For basic mods like an intake, Bama is a good choice. For mods more extensive, custom tune should be the only choice.
 
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