4 Point 0

This is not correct, but I see it keep being repeated.

The Akrapovic site clearly states 16.9 KW for the Cats (23Hp) , and 14 Kw (19hp) for the Cans. However if you do both you do not add the two numbers together. Whichever you do first, gets you the low hanging fruit.

Akra Cans and Akra CATS

nilaz

You are right I mixed the numbers although still the Akra statements is confusing.

They clearly mentioned Akra Cans is the FIRST upgrade where you can get 19hp.
For the cats they claim this OPTIONAL addition to the Slip On Line ( therefore to the Akra Cans) they provide maximum 24hp.

If Cans can add 19hp and cats 24hp I do not see a reason if you add both to a achieve up to 40hp which obviously is not the case.

Unfortunately there is no any dyno before and after and also Akra Dyno results compare a Carera without PSE which the Akra Cans obviously have significant benefits.

4 Point 0

The issue is, that somewhere along the curve with just Cans the MAX increase in delta is 19Hp. That may be at X rpm.
Then on another dyno, with just cats, the Max delta increase is 24 hp at Y rpm.

Neither of them add Max delta to the total HP. It is possible to add power in the Mid range, without increasing the over all Maximum Hp of the vehicle. There in lies the explanation.

I'm sure it will feel like you have an extra 40 Hp, but you won't. It depends where in the curve each part works on.

As a made up example, Cats may give you a 24hp buldge in the curve between 4,500rpm and 6,000 rpm. Whereas cans may be 19 hp from 3,300 to ,5,500. They overlap an area that is not increased. Also the numbers are nt added to max HP which may be at 6,600. (Made up numbers completely just as an example)

Another made up example, Say your car stock has 400HP. You add akra cats and dyno it comes out at 404Hp. You think I only made 4HP. At the point of max power you only made 4 hp, but when you study the curve, you would see at a point in the curve you gained 19 hp. Understand? The max gain from stock, somewhere along the curve is 19hp. Its not Max power and add this and add 19 hp. We wish it worked like that lol.

nilaz

Clear. Thanks for your explanation.

Nathan_

nilaz

Is it possible to install only Akra sport cats using the existing OEM PSE?
Or the sport cats of Akrapovic required mandatory installation of the Akra exhaust?

Rennolazine

PTS-BRG

Nilaz: Why on earth would you choose to use Akra cats with OEM? They are the highest cell count available at 300 cell, which are more restrictive than any other aftermarket cat. They are also the most expensive cat by far.
I can understand wanting Akra cats with an Akra exhaust to keep it consistent and from one manufacturer, but to buy just Akra cats seems crazy to me.

Many people buy the okra exhaust and use a third party cat just to keep the cost reasonable, but I have never heard of anyone doing what you suggest.
Short answer is that they will fit with PSE, design is the same.

nilaz

I am based in EU.
I plan to keep my MY2019 GTS under PAG extended warranty for the next 10 years as this car has been ordered based on my taste (RWD, RAS, LWBS and very little extras).
In case I install an aftermarket exhaust immediately I am out of the extended warranty program or I have every 2 years reinstall the OEM exhaust in order to get pictures of the car and send to PAG.
By installing Akra cats to the existing PSE I have almost the same benefits of every aftermarket system with few kgs more.
Every 2 years I will switch only the cats by myself and extend the warranty.
The sport cats will add the extra note in the great sound of the GTS especially in Sport+ mode.

I am not interested on any further tuning as the 450+ hp and massive torque of the GTS is much more than my driving skills.

Alternatively I could install Soul cats but as I am based in EU the cost is similar to Akra due to import and shipping cost.

4 Point 0

PTS- Don't ASSUME that just because the Akra cats are 300 Cell, that they are more restrictive. They have larger openings, and they are the top of the line. I think you would be shocked that the 300 cell Akra actually flows better than some 200 Cell cheaper versions. Its what Akra do best.

PTS-BRG

Nilaz: interesting points you make. Certainly any cat will improve sound, increase HP and will be an improvement over the stock cat.
And the fact that Akra costs the same or similar to Soul in your country also makes sense to me.
I dont think the PSE with cats will give you the same sound or performance as an aftermarket system, but it will be a big improvement over stock just with cats.
Your reasoning about PAG extended warranty also makes sense. Looks like you are doing it the right way..

4 point 0: A 300 cell cat has 300 cells. 93 octane has 93 octane. You can tell me that not all 93 octane is the same or that Akra;s magic 300 cell cats flow better than a 200 cell or 100 cell and I will again call BS.
It is scrubbing the exhaust with 300 cells. That will restrict flow more than a 200 cell, no matter how big the openings are or if they are using ceramic cores.
Until someone goes and does the testing, I will continue to believe that all of these cats are virtually identical and the flow will be similar between cell counts. Cost and design is all that varies, the cores are the same.
YES, I know that Akra is the only one making their own cores, but its still 300 cell and it will not flow like a 200. I am certain you will be buying the entire Akra system as well. Congrats.

4 Point 0

I have seen this on the dyno. I had cheap metallic cats on my M3. Around two months before I was getting a custom tune. The car sounded great. However when we were doing the dyno, the car was making less power than stock. (My M4 I went full catless, but it was very loud.)

We reverted the car back to stock tune and it was still way under stock level of power. The tuner blamed the Cats. I said they are brand new. He still blamed them. We removed them. Power was restored to full stock. Put tune on, and it was awesome.

He showed me the cats. They were clogged up. It had only been about 2 months since fitting, brand new. I won't ever put cheap cats on any of my vehicles again.

I asked around and it was a common thing. Most performance guys dislike metallic cats. They say ceramic or nothing.

Just on the Full Akra side of things........I don't want the car too loud. (I don't have any modded ones near me to hear in person.) So I might start with just the Akra Cats. Also the PSE isn't that bad in terms of flow and there isn't a huge gain from the Cans, when you have already done Headers and Cats. But the cans may just be the icing on the cake towards the end. I do like the Carbon fibre splitter and the tips. But would prefer if they offered them in black for the GTS.

4 Point 0

Well, you were right about this. I bought the Akra Cats. I want to fit them first, just to make sure they aren't too loud. Now that commits me to the rest.....So yeah....Pretty safe bet now.

reacher

I have a cab so I was worried about the same thing, didn't want it too loud especially with the top down. I have the full system and I can tell you it's definitely not too loud. Louder and sounds good, but it doesn't increase the volume a ton.

fsmich

I had the Akra cats on for 300 miles, and did not notice any sound or power difference. Wish I had done a before and after dyno. Ordered the cans and now have 2000mi/3 track days on the system. The volume is a marginal increase, the tone is smoother and more refined. You will not think it is too loud!