3.3TT KHARTUNERZ - NEW CATLESS SECONDARY DOWNPIPES Ark Performance

[StungBlueGT2]

Yes there are 10-20 Tq gains at fairly narrow low RPM. I wouldn't say this is the most usable range. You are trying to apply a WOT Tq gain to partial throttle applications in daily driving which you can't do. You could argue a suspected MPG/ efficiency increase I guess. If you go WOT the car will shift and you never use this 2800-3800 RPM range. This car already has tons of power for daily driving and if I need more I push the pedal harder. Dynos are full throttle and performance measures are full throttle so that's what I'm focusing on. I just don't think a partial throttle gain is a real thing as who knows the difference between 40% throttle and 45% throttle. If you do go full throttle short shifting, which isn't a great idea for knock and stress/loads, then you do have a point it is a good mod.

Agreed, the biggest 20wtq gains are in a narrow RPM range but looks like a minimum of 5whp from the beginning of the results. Most likely a 5-20wtq gain throughout the entire max torque range(1300-4500rpm). So unless you’re at WOT all the time that gain would be in the most usable range, especially for daily driving.

Also, power gains aren’t specific to WOT only. If the engine is simply more efficient at making power then that effect will be true at all times, not just at WOT. Actually, there may be even more noticeable gains at partial throttle since the engine doesn’t need to work as hard for equal acceleration. Unfortunately nobody does half throttle dyno runs so we will never know for sure but I bet the gains at part throttle would be the same if not greater than WOT. The few Stingers I know that have 2ndDPs sure feel quicker off the line at any throttle input not only while flooring it.

As I said before if the only focus is WOT gains near redline then the 5-20wtq gains from 1300-4500RPM doesn’t matter much, but most people would enjoy that extra power the other 95% of the time.

On a brighter note, the catbacks seem to be about 10-15 HP so you get to sound cool and go a little faster too.
My ark grip was 10 HP. 2 before dynos from different stingers on the same dyno hit 243, mine hit 253. So assuming my car was average.

Very true but if catbacks will produce 10-15HP by removing exhaust restrictions of the mufflers, then it only makes sense that removing a bigger restriction(cats) will produce the same if not better gains throughout the whole rpm range.

Guess will will have to wait until more dynos are provided, but so far 20wtq from mrsmoofy and 20whp from mistermac means there are good gains to be had from 2ndDPs one way or the other.

 

[Tonkabob]

Agreed, the biggest 20wtq gains are in a narrow RPM range but looks like a minimum of 5whp from the beginning of the results. Most likely a 5-20wtq gain throughout the entire max torque range(1300-4500rpm). So unless you’re at WOT all the time that gain would be in the most usable range, especially for daily driving.

Also, power gains aren’t specific to WOT only. If the engine is simply more efficient at making power then that effect will be true at all times, not just at WOT. Actually, there may be even more noticeable gains at partial throttle since the engine doesn’t need to work as hard for equal acceleration. Unfortunately nobody does half throttle dyno runs so we will never know for sure but I bet the gains at part throttle would be the same if not greater than WOT. The few Stingers I know that have 2ndDPs sure feel quicker off the line at any throttle input not only while flooring it.

As I said before if the only focus is WOT gains near redline then the 5-20wtq gains from 1300-4500RPM doesn’t matter much, but most people would enjoy that extra power the other 95% of the time.
Very true but if catbacks will produce 10-15HP by removing exhaust restrictions of the mufflers, then it only makes sense that removing a bigger restriction(cats) will produce the same if not better gains throughout the whole rpm range.

Guess will will have to wait until more dynos are provided, but so far 20wtq from mrsmoofy and 20whp from mistermac means there are good gains to be had from 2ndDPs one way or the other.

My point was at half throttle there likely are no gains since the exhaust would have virtually no restriction pumping half the volume of exhaust through it. There are some small gains at WOT that you will only see in first gear.

 

[Secondchance]

Agreed, the biggest 20wtq gains are in a narrow RPM range but looks like a minimum of 5whp from the beginning of the results. Most likely a 5-20wtq gain throughout the entire max torque range(1300-4500rpm). So unless you’re at WOT all the time that gain would be in the most usable range, especially for daily driving.

Also, power gains aren’t specific to WOT only. If the engine is simply more efficient at making power then that effect will be true at all times, not just at WOT. Actually, there may be even more noticeable gains at partial throttle since the engine doesn’t need to work as hard for equal acceleration. Unfortunately nobody does half throttle dyno runs so we will never know for sure but I bet the gains at part throttle would be the same if not greater than WOT. The few Stingers I know that have 2ndDPs sure feel quicker off the line at any throttle input not only while flooring it.

As I said before if the only focus is WOT gains near redline then the 5-20wtq gains from 1300-4500RPM doesn’t matter much, but most people would enjoy that extra power the other 95% of the time.
Very true but if catbacks will produce 10-15HP by removing exhaust restrictions of the mufflers, then it only makes sense that removing a bigger restriction(cats) will produce the same if not better gains throughout the whole rpm range.

Guess will will have to wait until more dynos are provided, but so far 20wtq from mrsmoofy and 20whp from mistermac means there are good gains to be had from 2ndDPs one way or the other.

This platform as a whole has parts that produce power by adding / removing, but we're still limited in knowing the true benefits individual parts can truly produce until the ECU is full unlocked and tuners have the chance to really push the vehicle to it's potential.

It is rather fishy that the cat being removed seemingly adds next to no power. Almost makes it seem like the O2 housing / primary dp is the actual restriction point on the vehicle.

 

[Tonkabob]

Here is the link to the Primary dp dynos, big tq and hp gains on stock boost and nice Tq gains on high boost, but not much HP.
The secondary cat is like having a funnel after a funnel, the first one is doing most the work.

Drag/Acceleration - Kia Stinger 1/4 Mile Times

 

[StungBlueGT2]

My point was at half throttle there likely are no gains since the exhaust would have virtually no restriction pumping half the volume of exhaust through it. There are some small gains at WOT that you will only see in first gear.

I get your point and agree it may not be a typical power gain at part throttle because restrictions are less of a factor.

However I still feel that a more efficient engine will access that additional power at all times. Another words, it will simply take less throttle to achieve the same amount of acceleration. So in theory, adding more torque from 1300-4500rpm will make 40% throttle feel the same as 50% throttle on a stock car.

Not sure how you would measure or compare that, but still feel that is a gain in performance one way or the other.

 

[StungBlueGT2]

It is rather fishy that the cat being removed seemingly adds next to no power. Almost makes it seem like the O2 housing / primary dp is the actual restriction point on the vehicle.

Seems fishy overall since muffler deletes/catbacks add significant power themselves and must be less of a restriction than a catalytic converter.

But agree the primary DP is the most restrictive part of the exhaust and shows the biggest gains on stock Stingers.

Since Tork made 44whp with just intakes & muffler deletes I wonder how much more power you could get with only intakes and DPs. We might be able to get 60whp+ from just two bolt-ons without a chip/tune needed.

 

[Secondchance]

Modifications rarely stack power gains, especially when they are inter related. The other issues without a tune is cels(even just the threat of them). A full turbo back itself is probably good for a nice 35-40 whp through most of the power band, especially on a tune that can take advantage of it.

I think the sweet spot on this car will be the same as other turbo applications. Full turboback, intake(s), intercooler and piping and tune. There's no reason this car won't be a rocketship at that point.

 

[Tonkabob]

Seems fishy overall since muffler deletes/catbacks add significant power themselves and must be less of a restriction than a catalytic converter.

But agree the primary DP is the most restrictive part of the exhaust and shows the biggest gains on stock Stingers.

Since Tork made 44whp with just intakes & muffler deletes I wonder how much more power you could get with only intakes and DPs. We might be able to get 60whp+ from just two bolt-ons without a chip/tune needed.

In Torks full mods HP adds video they said +12 on muffler delete and +16 for intake so +28 stacked.
I also asked him on his cat deletes and he clarified that he removed all 4 cats and saw +25hp.

 

[StungBlueGT2]

Modifications rarely stack power gains, especially when they are inter related. The other issues without a tune is cels(even just the threat of them). A full turbo back itself is probably good for a nice 35-40 whp through most of the power band, especially on a tune that can take advantage of it.

I think the sweet spot on this car will be the same as other turbo applications. Full turboback, intake(s), intercooler and piping and tune. There's no reason this car won't be a rocketship at that point.

Yes and no. Most mods do stack gains but not 1:1 or at 100% of each individual gain. Typical everything after the first mod only adds another 30-50% and causes diminishing returns. Airflow mods generally stack better, especially if one is on the intake side and one is on the exhaust side allowing them to work in tandem.

Im aware of the CEL/overboost issues removing the primary cats & O2 sensors and was thinking highflow cats like the UP DPs combo kit.

That’s worth 46whp/62wtq by itself and stacked with intakes it should make close to max gains of 60whp/75wtq together.

And I agree, the sweet spot is FBO with a tune, but there are already multiple Stingers setup that way and pushing 460whp+, and almost 500whp with WMI on stock turbos. That rocket ship has already taken off.

In Torks full mods HP adds video they said +12 on muffler delete and +16 for intake so +28 stacked.
I also asked him on his cat deletes and he clarified that he removed all 4 cats and saw +25hp.

The 44whp reference was directly from John/Tork himself.Pretty Damn Impressive Results
28whp is probably just peak HP gains, but still impressive.

And 25whp sounds conservative for fully catless, but still similar to the 33whp peak gains the highflow cat UP combo made above. Maybe the FMIC & tune helped make the extra power but either way all very healthy gains by simply removing airflow restrictions.

 

[washguy]

My Ark dp's will be here next week....Yippeee....Nick is one solid guy for sure...kudos to Nick ! I promised myself I wouldn't tinker with the exhaust, and let the Stinger be a true street sleeper,and ive got two loud vehicles already if I want to make noise....I guess peer pressure got me . So we know that some of the before and after dynos sukked on a couple tests. So last week I went over to the shop that changed plugs for me...they have a mustang dyno,and seem to be knowledgeable on the gtr's and other high end stuff...geez they are expensive....so long story short....im thinkin this is the way to do it
make 3 runs before install of dp's.......map 0 map2 map 3....but in reverse order map 3 first....then let them install the dps'......then drive the car for a few days or a week....then go back and make the 3 pulls again.....is that good ...or do yall have a better idea? Wash

 

[Pnbnationsbest]

IDEALLY @washguy you want all of your pulls to be same day as close to each other as possible. So, baseline pulls, install parts and then comparison pulls. You want to eliminate as many environmental factors as possible. Daily differing heat and humidity will wreak havoc on dyno runs, because they alter the air density.

Prior to having any pulls done I recommend doing your own research to find out what gear (W/O looking I'm guessing 5th) is the closest to a 1:1 ratio.

 

[Angel]

My Ark dp's will be here next week....Yippeee....Nick is one solid guy for sure...kudos to Nick ! I promised myself I wouldn't tinker with the exhaust, and let the Stinger be a true street sleeper,and ive got two loud vehicles already if I want to make noise....I guess peer pressure got me . So we know that some of the before and after dynos sukked on a couple tests. So last week I went over to the shop that changed plugs for me...they have a mustang dyno,and seem to be knowledgeable on the gtr's and other high end stuff...geez they are expensive....so long story short....im thinkin this is the way to do it
make 3 runs before install of dp's.......map 0 map2 map 3....but in reverse order map 3 first....then let them install the dps'......then drive the car for a few days or a week....then go back and make the 3 pulls again.....is that good ...or do yall have a better idea? Wash

You will be happy with you downpipes regardless of results trust me ..... don’t get too caught up on the results brother!

 

[Chris71]

My Ark dp's will be here next week....Yippeee....Nick is one solid guy for sure...kudos to Nick ! I promised myself I wouldn't tinker with the exhaust, and let the Stinger be a true street sleeper,and ive got two loud vehicles already if I want to make noise....I guess peer pressure got me . So we know that some of the before and after dynos sukked on a couple tests. So last week I went over to the shop that changed plugs for me...they have a mustang dyno,and seem to be knowledgeable on the gtr's and other high end stuff...geez they are expensive....so long story short....im thinkin this is the way to do it
make 3 runs before install of dp's.......map 0 map2 map 3....but in reverse order map 3 first....then let them install the dps'......then drive the car for a few days or a week....then go back and make the 3 pulls again.....is that good ...or do yall have a better idea? Wash

Dude that's perfect! By way it will be a bit louder in the cabin and out but still a sleeper
I still stand by my two points, as part of overall package is a fantastic upgrade, and I noticed more TQ! In addition removing the two cats will free up flow and reduce exhaust tempts a bit, couple that with cooler air in reducing EGT out and the midpipes can help run a cooler system overall and that is good for the whole car

Washguy, pay close attention to your butt Dyno, then after I stall run a couple and respond if u feel any TQ difference...not sicentific and could be plecbo affect but fun anyway
Good luck, excited to hear back.

 

[Tonkabob]

I turned the engine sound up on custom and my car is faster now too!

 

[washguy]

I was thinking of giving the ecu some love with the dp's for a couple of days before doing the "after pull"
ive been monitoring the DA and its steady mostly for this 95 plus weather 3500 yesterday !...and ill check the 1:1 gearing ...im thinkin 5th gear too.... Wash

 

[washguy]

Okie dokie These Ark Dp's from Nick are first class ! Nice welds...no make it xcellent welds !
So im jonesing to get em on after Wifey gave me the "stink eye" .....she wanted to know if these will help her beat that amg Mercedes she sees all the time at the grocery store.....wait a sec...Oh snap ...so sumthins up maybe? Why does it take 3 hours to get some groceries when the store is 2 miles away? Oh well.....on to getting them installed.....shop is busy till next week....so mid week im thinkin to do a baseline then install.....then put a few days on em then dyno again.....lets do this right.... Wash

 

[washguy]

Dude that's perfect! By way it will be a bit louder in the cabin and out but still a sleeper
I still stand by my two points, as part of overall package is a fantastic upgrade, and I noticed more TQ! In addition removing the two cats will free up flow and reduce exhaust tempts a bit, couple that with cooler air in reducing EGT out and the midpipes can help run a cooler system overall and that is good for the whole car

Washguy, pay close attention to your butt Dyno, then after I stall run a couple and respond if u feel any TQ difference...not sicentific and could be plecbo affect but fun anyway
Good luck, excited to hear back.

Chris Thanks for the input ! I always trust my butt dyno having the exhaust breathe easier has got to help....the DIY intakes sure helped the car by 2 tenths....and it moved the torque up a bit which is to my liking.....heres how I know....before the intakes the car from a dead stop smoked the tires then settled down on the 1...2 shift it chirped.......so now with the DIY intakes...the car launches without too much spin....but when it gets to to redline on the 1...2 shift is where it smokes the tires now....and when driving 30/40 mph...goose it and it smokes the tires.....the torque in my opinion moved up a bit....I like it Wash

 

[JDM_Man]

Any update on this?

 

[MrSmoofy]

What kind of update are you looking for?

 

[washguy]

Any update on this?

Sorry guys for the delay on the install of the dp's...... the shop is slammed and ive been tied up with a bunch o' crap.......im tired of looking at the box....ill get on the dyno as soon as I can Wash