Kooks vs LTH headers

[Tezz500]

Anyone have any comparison data?

I had Kooks on the 14… trying to justify the extra costs vs the LTH brand.

It’s like a $740+ difference when you include the X/H pipes…

Long Tube Headers FDLH00011T 2011-2014 Shelby GT500 1-7/8" Longtube Headers

The OEM headers on the 5.4L / 5.8L GT500 leave a lot to be desired. The stock unit is manufactured with the goal of suppressing the motors sound as much as possible. This sound deadening robs the motor of vital flow and horsepower. Take your horsepower back with the LTH Long Tube Headers!The LTH...

www.lethalperformance.com

Kooks 1-7/8" x 3" SS Headers. 2011-2014 Shelby GT500. - 11422400

Lethal Performance is proud to announce the Kooks Custom Longtube Header System for the Shelby GT500. If you guys don't know Kooks has been bending and welding custom headers for over 30 years! The end result is one of the nicest works of art that you could ever imagine putting on your car. The...

www.lethalperformance.com

 

[1 Alibi 2]

Don't know anything about LTH.
I went with Kooks twice, mainly because they offer a " green " cat.
I'm in an inspection state, & had to do nothing to pass state inspection..

 

[darksykal]

Don't know anything about LTH.
I went with Kooks twice, mainly because they offer a " green " cat.
I'm in an inspection state, & had to do nothing to pass state inspection..

Same here lol

 

[Tezz500]

Same here lol

CO is alittle weird.. we have these drive by testing vans… that if you buzz 1 twice and pass you’re good and don’t have to go to the inspection station.

Local Tuner is saying the green cats won’t pass emissions here though so…. Anyway, my questions on the headers and HP/TQ gains. I’m familiar with the Kooks. Thought they were amazing quality…. Watching some vids and the LTHs seem great as well.

 

[1 Alibi 2]

State inspection in N.J. plugs into the OBDII port, no visual.
Both my 11 & 14 passed with no issue.
Also:

The Kooks green headers have an EPA stamp on the cats and are 49 or 50 state legal, so you might get lucky like some of the others and not even have to fight the CEL gremlins.

 

[fuelforfire87]

The Kooks are nice and had them on both my previous mustangs. However with their current pricing I decided to take a chance and order the LTH headers and x-pipe on black Friday. When I inspected them after I received them, the build quality seems to be on par with the other top tier header manufacturers. I am having them installed later next month. From watching a few youtube videos of other people having them installed it appears there can be some slight fitment issues with the stock k member, but nothing major that can't be remedied with minor modification of the k member. As far as passing inspection I would say kooks is best bet with their green cats but they definitely charge a premium for it. FWIW LTH also has an ECO catted x-pipe that also supposedly has GESI cats which I believe are who make the green cats for kooks.

Ford Mustang ('11-'14) S197 X-Pipe Exhaust System

longtubeheaders.com

 

[Tezz500]

The Kooks are nice and had them on both my previous mustangs. However with their current pricing I decided to take a chance and order the LTH headers and x-pipe on black Friday. When I inspected them after I received them, the build quality seems to be on par with the other top tier header manufacturers. I am having them installed later next month. From watching a few youtube videos of other people having them installed it appears there can be some slight fitment issues with the stock k member, but nothing major that can't be remedied with minor modification of the k member. As far as passing inspection I would say kooks is best bet with their green cats but they definitely charge a premium for it. FWIW LTH also has an ECO catted x-pipe that also supposedly has GESI cats which I believe are who make the green cats for kooks.

Ford Mustang ('11-'14) S197 X-Pipe Exhaust System

longtubeheaders.com

Awesome. Thanks for the input. Looking forward to seeing some numbers from your build after install.

 

[fuelforfire87]

Awesome. Thanks for the input. Looking forward to seeing some numbers from your build after install.

Thanks, will be going e85 as well so will probably be booking a dyno session when I get the revised tune

 

[darksykal]

I will say as a heads up with Kooks long tubes- their fitment is shit.
they're way too tight and I'm currently dealing with now having to replace my steering shaft with a thiner one cause its touching.

Be prepared for the possibility of a bad fit.

 

[Tezz500]

I will say as a heads up with Kooks long tubes- their fitment is shit.
they're way too tight and I'm currently dealing with now having to replace my steering shaft with a thiner one cause its touching.

Be prepared for the possibility of a bad fit.

I had kooks on my 2014 and they were phenomenal fit and finish.

 

[SID297]

@SteveG@Lethal can probably help with this one.

 

[darksykal]

I had kooks on my 2014 and they were phenomenal fit and finish.

when did you install them? recently?
i think covid changed a lot in regards to supply and they make to order now which is probably why they have more fitment issues now than before (and massive lead-times- I waited about 8 weeks for mine)

I'm not saying everyone has issues- but I know for a fact im not the only one that had issues with them rubbing steering shafts.

 

[Tezz500]

when did you install them? recently?
i think covid changed a lot in regards to supply and they make to order now which is probably why they have more fitment issues now than before (and massive lead-times- I waited about 8 weeks for mine)

I'm not saying everyone has issues- but I know for a fact im not the only one that had issues with them rubbing steering shafts.

Nah I put headers on that one back in 14/15 I believe.

I just want performance numbers between the two. If I’m going to pull the trigger on a pain in the ass install like headers, I wanna know I’m getting comparable numbers if I decide to go with the LTH brand.

 

[darksykal]

Nah I put headers on that one back in 14/15 I believe.

I just want performance numbers between the two. If I’m going to pull the trigger on a pain in the ass install like headers, I wanna know I’m getting comparable numbers if I decide to go with the LTH brand.

makes sense-

this is my before and after just the kooks headers + vmp heat exchanger (+ clutch)
(mustang dyno)

before:


after:

 

[fuelforfire87]

Nah I put headers on that one back in 14/15 I believe.

I just want performance numbers between the two. If I’m going to pull the trigger on a pain in the ass install like headers, I wanna know I’m getting comparable numbers if I decide to go with the LTH brand.

Honestly the only real way to know the power difference between brand A and brand B headers would be to dyno the car with brand A installed, then uninstall and install brand B and re-dyno the same day. Given the amount of time it takes to install headers on these cars, that would be practically impossible. Your splitting C hairs between all the good header companies as far as power gains. I'd bet money that all good headers (Kooks, ARH, Stainless Works, LTH, etc.) would be within 5 HP of each other on a stock motor car, which is not a measurable difference anyways because back to back dyno runs can vary by that much. Heck, Mustang Lifestyle made 1350whp with his GT500 through LTH 1-7/8" headers, so obviously they must flow pretty well. Also @Turbo98GT has made some pretty stout numbers with the LTH headers as well.

Also @darksykal interesting dyno numbers. I wonder why on the after video the correction factor HP numbers are lower than the actual HP numbers. Was the temperature significantly cooler than when the car was dynoed before headers?

 

[Tezz500]

Honestly the only real way to know the power difference between brand A and brand B headers would be to dyno the car with brand A installed, then uninstall and install brand B and re-dyno the same day. Given the amount of time it takes to install headers on these cars, that would be practically impossible. Your splitting C hairs between all the good header companies as far as power gains. I'd bet money that all good headers (Kooks, ARH, Stainless Works, LTH, etc.) would be within 5 HP of each other on a stock motor car, which is not a measurable difference anyways because back to back dyno runs can vary by that much. Heck, Mustang Lifestyle made 1350whp with his GT500 through LTH 1-7/8" headers, so obviously they must flow pretty well. Also @Turbo98GT has made some pretty stout numbers with the LTH headers as well.

Also @darksykal interesting dyno numbers. I wonder why on the after video the correction factor HP numbers are lower than the actual HP numbers. Was the temperature significantly cooler than when the car was dynoed before headers?

By that Rationale... Why waste the money on the Kooks? hmmm

LTH FDLH00011T 2011-2014 Shelby GT500 1-7/8" Longtube Headers $1,107.04

Kooks 1-7/8" x 3" SS Headers. 2011-2014 Shelby GT500. - 11422400 $1585.81

 

[fuelforfire87]

By that Rationale... Why waste the money on the Kooks? hmmm

LTH FDLH00011T 2011-2014 Shelby GT500 1-7/8" Longtube Headers $1,107.04

Kooks 1-7/8" x 3" SS Headers. 2011-2014 Shelby GT500. - 11422400 $1585.81

A lot of it is you're paying for the Kooks name. Kooks has been around a lot longer than LTH and with their repuation they can command a higher price-point. Also one thing that Kooks prides themselves with is that all the primaries in their headers are one single piece, not a few pieces welded together like most other header companies, which leaves less potential failure points. In this case, the construction is superior. Another difference is that kooks has 3" collecters where the LTH are 2.75". Not a huge difference unless you are trying to make over 1000whp but if you are deadset on running a full 3" exhaust you would need to go with Kooks or one of the other companies besides LTH.

Sent from my SM-S906U using Tapatalk

 

[darksykal]

Honestly the only real way to know the power difference between brand A and brand B headers would be to dyno the car with brand A installed, then uninstall and install brand B and re-dyno the same day. Given the amount of time it takes to install headers on these cars, that would be practically impossible. Your splitting C hairs between all the good header companies as far as power gains. I'd bet money that all good headers (Kooks, ARH, Stainless Works, LTH, etc.) would be within 5 HP of each other on a stock motor car, which is not a measurable difference anyways because back to back dyno runs can vary by that much. Heck, Mustang Lifestyle made 1350whp with his GT500 through LTH 1-7/8" headers, so obviously they must flow pretty well. Also @Turbo98GT has made some pretty stout numbers with the LTH headers as well.

Also @darksykal interesting dyno numbers. I wonder why on the after video the correction factor HP numbers are lower than the actual HP numbers. Was the temperature significantly cooler than when the car was dynoed before headers?

yah not sure on the wcf

car was dynod before headers in about 60ish degree weather

after headers was dynod in about 30 degree weather

 

[fuelforfire87]

yah not sure on the wcf

car was dynod before headers in about 60ish degree weather

after headers was dynod in about 30 degree weather

That makes sense then. Doing a quick google search STD correction factor corrects for a temperature of 60 degrees F, and SAE corrects for a temperature of 77 degrees F. Bottom line is cooler air is more dense, hence able to make more power than what it would have made in the conditions specified by whatever correction factor the dyno was set to.

 

[Tezz500]

Here’s the deal.

I recently sold a 2014 Shelby GT500 with:
Full Kooks exhaust
VMP GEN3R
2.8 upper
1050 injectors
MHS stage 1 cams
FRPP 65mm TB
JLT 123 CAI
VMP fuel pump boosters

Some other mods clutch suspension etc.

Car made 762rwhp on a very conservative tune in the middle of July. I specifically asked for a very conservative tune as to not grenade the motor.

So I am familiar with the kooks. The quality was phenomenal.

I am building a very similar set up with this 2013 I just bought back in October. However, I am in Colorado now and the tune is going to be different and should allow for me to climb beyond the 800hp ceiling. (Dyno numbers being corrected for altitude)

My plan is to see what we can make without headers first. I’ll keep the forum posted.

What I am asking for, as stated in the OP is some comparisons, numbers wise, on the LTH brand vs Kooks.

Anyone happen to have any of that data floating around?

Because when I pull the motor to swap the rods/pistons, I’m gonna add headers.