Help: The best diameter DP/FP for my setup

Prozento

Senior Member
First Name
Alex
Joined
May 7, 2018
Threads
32
Messages
132
Reaction score
37
Location
Israel
Vehicle(s)
Civic FD
Country flag
Hello everyone

My car is a Hatchback FK7 sport model with manual transmission. In a few days, I will order an Intercooler and already has the Ktuner V2 with 21PSI tune.
The next thing on my list is a DP/FP combo but I struggle to decide about the diameter and thus cant decide witch company to give my money.
After reading a lot of topics here and making a small R&D I understood these things and choose 2 companies to focus on them:

PRL: Has full 3" DP/FP combo. Has 300CEL catted option.
27WON: Has 3" DP and 2.5" FP combo. Has 200CEL catted option. Have a small gap in the OEM heat shield after installation.
Catted vs cattless: Still not decided but since I don't want it to be too raspy and loud I think I'll go with catted in the end.
Stock exhaust: 2". As for now, I don't plan to replace it. The only reason that can force me to change it will be too much noise after installing DP/FP combo.
The difference in price is almost none for the cattless and 100$ for the catted.

So now for the questions...
The simple one is - witch combo is better for my setup (FMIC and tune for now)? Not planning to upgrade the turbo in the near future for sure.
The deeper is - what consequences can be to making 3" combo ran into a bottleneck 2" stock exhaust? (it will answer the first one too I guess)
The hardest is - and I know its subjective for every ear - the sound I will get from DP/FP combo installation with the stock exhaust...Is it "rice" as **** or it something I will be able to live with?

Thanks to everyone who spent time reading this
Looking forward for your replies
Sincerely
Prozento
Sponsored

 

Hondanickx

Senior Member
First Name
Nick
Joined
Jun 10, 2018
Threads
61
Messages
1,026
Reaction score
780
Location
Belgium
Vehicle(s)
1998 civic hatch , 2018 civic sedan 1.5T
Build Thread
Link
Vehicle Showcase
1
Country flag
If you're going to keep the oem exhaust and not going for a bigger turbo i would go with 27won.
From 3" to 2.5" to 2" is a nice taper and is enough for your setup.
Also do get the catted version as this keeps noise down and doesn't effect flow that much.
 
OP
OP

Prozento

Senior Member
First Name
Alex
Joined
May 7, 2018
Threads
32
Messages
132
Reaction score
37
Location
Israel
Vehicle(s)
Civic FD
Country flag
If you're going to keep the OEM exhaust and not going for a bigger turbo I would go with 27won.
From 3" to 2.5" to 2" is a nice taper and is enough for your setup.
Also do get the catted version as this keeps noise down and doesn't affect flow that much.
First of all thanks for the answer
At what power, this setup will make any problem?
Even with the turbo but without flex fuel kit (only 91 and 93 octanes available in my country) I don't think it's possible to pass the 400 HP anyway. Let's say 260 with FMIC/DP/FP/Intake combo with a tune and ...just speculating now.... 350-380HP with the 27WON turbo.

So considering this, will it ever be a problem with 3-2.5-2" setup? I will never go further from 27WON turbo on the power side even if I won't decide to stop after regular "bolts-on" because bigger turbo comes with brakes and clutch and all this stuff is expensive as hell.
 

Anger

Senior Member
First Name
Nick
Joined
Sep 24, 2018
Threads
4
Messages
380
Reaction score
227
Location
Greece
Vehicle(s)
FK7,RW2,RD1,RD5,RE5,RU1,FK1,FN2,EP3
Vehicle Showcase
1
Country flag
I would agree. It would make sense to gradually drop the pipe diameter instead of going directly from 76mm to 50mm. I will do the same thing since my stock catback is also 50 or 55mm cant remember exactly and then splits to two 48mm pipes for each muffler.

I would rather go for the catless version but with EU regulations being so strict about emissions, a catted tuned version is more sensible. I do not know however what difference a 200 VS a 300 cat makes for emissions. RV6 also uses a 300 cel cat. If someone can help with that, that would be a decision maker for me with either PRL or RV6. If 200 VS 300 makes no difference, then I'd go 27WON. Only reason I haven't moved forward with this a long time ago is that I cannot disable the O2 sensor yet via my Ktuner (stuck at initial support). Before deciding either way catted or not, I need to ask my tuner he can set the car up in a very specific way when ECO-mode is on and thus being able to pass the emissions test even without a cat as long as ECO mode is on.

In any case, the front pipe is something that can easily be manufactured by a proper exhaust shop. If you were based in USA, then of course it would be better to go for the full set. But since import charges are applicable in Ukraine I suppose, maybe its better to have a look at a local shop. It a small piece without too many bends and most if not all exhaust shops can do it. I had custom mufflers made and I can tell you that the stock design isn't the easiest to copy but it was doable. A front-pipe is piece of cake for a proper exhaust shop. It will save you some money.
 

Anger

Senior Member
First Name
Nick
Joined
Sep 24, 2018
Threads
4
Messages
380
Reaction score
227
Location
Greece
Vehicle(s)
FK7,RW2,RD1,RD5,RE5,RU1,FK1,FN2,EP3
Vehicle Showcase
1
Country flag
Hello everyone

My car is a Hatchback FK7 sport model with manual transmission. In a few days, I will order an Intercooler and already has the Ktuner V2 with 21PSI tune.
The next thing on my list is a DP/FP combo but I struggle to decide about the diameter and thus cant decide witch company to give my money.
After reading a lot of topics here and making a small R&D I understood these things and choose 2 companies to focus on them:

PRL: Has full 3" DP/FP combo. Has 300CEL catted option.
27WON: Has 3" DP and 2.5" FP combo. Has 200CEL catted option. Have a small gap in the OEM heat shield after installation.
Catted vs cattless: Still not decided but since I don't want it to be too raspy and loud I think I'll go with catted in the end.
Stock exhaust: 2". As for now, I don't plan to replace it. The only reason that can force me to change it will be too much noise after installing DP/FP combo.
The difference in price is almost none for the cattless and 100$ for the catted.

So now for the questions...
The simple one is - witch combo is better for my setup (FMIC and tune for now)? Not planning to upgrade the turbo in the near future for sure.
The deeper is - what consequences can be to making 3" combo ran into a bottleneck 2" stock exhaust? (it will answer the first one too I guess)
The hardest is - and I know its subjective for every ear - the sound I will get from DP/FP combo installation with the stock exhaust...Is it "rice" as **** or it something I will be able to live with?

Thanks to everyone who spent time reading this
Looking forward for your replies
Sincerely
Prozento
Forgot to mention that in installation videos, I ve seen that the turbo inlet pipe has to be removed for the downpipe to be installed. If you go for 27WON, maybe you should also consider their turbo inlet pipe. Doesnt cost much, it will save you shipping costs plus according to them your intake will sound even better. No gains with the stock turbo but for a bit of sound and looks, the cost is bearable.
 


Hondanickx

Senior Member
First Name
Nick
Joined
Jun 10, 2018
Threads
61
Messages
1,026
Reaction score
780
Location
Belgium
Vehicle(s)
1998 civic hatch , 2018 civic sedan 1.5T
Build Thread
Link
Vehicle Showcase
1
Country flag
I would also highly recommend Wagner tuning for anyone in europe.
Allthough they don't make a downpipe for the 1.5t yet( only the fk8)
Their downpipes use the HJS cats which are widely used in OEM and racing applications.
 

kytos

Senior Member
First Name
Marcos
Joined
Apr 18, 2018
Threads
7
Messages
601
Reaction score
416
Location
Madrid - Spain
Website
www.instagram.com
Vehicle(s)
CIVIC SPORT 1.5t 2017 EUDM
Country flag

bbeem

Senior Member
First Name
Ben
Joined
Nov 10, 2018
Threads
38
Messages
1,131
Reaction score
617
Location
Iowa
Vehicle(s)
19 si sedan, FZ1, CR450R, Shadow 750
Vehicle Showcase
1
Country flag
Rv6 and prl use 300 cell cat, 27won 200 cell. Rv6 has 2 different output flanges, one to use with factory front pipe, one to bolt to their 3" front pipe. I did this and wrapped the downpipe and front pipe and used the top shield, I forget if I used the side shield over the wrap. The sound of the dp and front with stock exhaust was better but not enough for me. If you're leaving your factory res and mufflers for sure don't upgrade front pipe, the restriction is after the front.

Don't install the turbo inlet pipe for your build. It's for pairing with large turbo, large MAF and sri/cai. And it was sold out in 8 hours for $340 anyway.

Also you'll probably want to disable the code in ktuner. Even with my catted dp I was able to throw the cel twice in 20k miles.

Changing the dp should be as easy as turning a wrench and snaking it up from the bottom EXCEPT Honda used jam nuts on the studs in the manifold and you might even pull some studs out! Be careful with this, and replace with proper hardened nuts and throw the jam nuts away.
 

bbeem

Senior Member
First Name
Ben
Joined
Nov 10, 2018
Threads
38
Messages
1,131
Reaction score
617
Location
Iowa
Vehicle(s)
19 si sedan, FZ1, CR450R, Shadow 750
Vehicle Showcase
1
Country flag
Only reason I haven't moved forward with this a long time ago is that I cannot disable the O2 sensor yet via my Ktuner (stuck at initial support).
There's a box to tick to disable this sensor. The bottom box p0138. I ran rv6 catted and front and it sounded different. Then invidia R400 and it sounds and runs great. I don't like the sound of just the dp enough but it is better than wisper quiet stock. I recommend the Rv6 but you also probably can't go wrong with the prl or 27won and they're all the same price. Also for install I went up from the bottom instead of taking turbo inlet off. And for 200 vs 300 cell they should pass emissions provided they're hot before the test.
Honda Civic 10th gen Help: The best diameter DP/FP for my setup upload_2019-3-30_22-24-4
 
OP
OP

Prozento

Senior Member
First Name
Alex
Joined
May 7, 2018
Threads
32
Messages
132
Reaction score
37
Location
Israel
Vehicle(s)
Civic FD
Country flag
Thanks for the answer!...still something bothers me...
Let's say we will erase the current statement that I won't replace the exhaust...because it can change in the future.

If I will buy only DP for now ...
1. Is it OKthat 3" run into stock 2"...won't be some negative effect from this "bottle neck"

Now if the answer is "yes"...why not to add few bucks and get the FP already? If the money is not the question.

2. Will I lose something from not installing the 2.5 FP / 3" FP until I will decide what to do with the exhaust? This will actually answer the 1. Add on heh
 


Hondanickx

Senior Member
First Name
Nick
Joined
Jun 10, 2018
Threads
61
Messages
1,026
Reaction score
780
Location
Belgium
Vehicle(s)
1998 civic hatch , 2018 civic sedan 1.5T
Build Thread
Link
Vehicle Showcase
1
Country flag

Myx

Senior Member
Joined
Mar 6, 2016
Threads
79
Messages
2,166
Reaction score
2,042
Location
Delaware
Vehicle(s)
2018 Honda Civic EX (Hatchback/CVT)
Vehicle Showcase
1
Country flag
Hello everyone

My car is a Hatchback FK7 sport model with manual transmission. In a few days, I will order an Intercooler and already has the Ktuner V2 with 21PSI tune.
The next thing on my list is a DP/FP combo but I struggle to decide about the diameter and thus cant decide witch company to give my money.
After reading a lot of topics here and making a small R&D I understood these things and choose 2 companies to focus on them:

PRL: Has full 3" DP/FP combo. Has 300CEL catted option.
27WON: Has 3" DP and 2.5" FP combo. Has 200CEL catted option. Have a small gap in the OEM heat shield after installation.
Catted vs cattless: Still not decided but since I don't want it to be too raspy and loud I think I'll go with catted in the end.
Stock exhaust: 2". As for now, I don't plan to replace it. The only reason that can force me to change it will be too much noise after installing DP/FP combo.
The difference in price is almost none for the cattless and 100$ for the catted.

So now for the questions...
The simple one is - witch combo is better for my setup (FMIC and tune for now)? Not planning to upgrade the turbo in the near future for sure.
The deeper is - what consequences can be to making 3" combo ran into a bottleneck 2" stock exhaust? (it will answer the first one too I guess)
The hardest is - and I know its subjective for every ear - the sound I will get from DP/FP combo installation with the stock exhaust...Is it "rice" as **** or it something I will be able to live with?

Thanks to everyone who spent time reading this
Looking forward for your replies
Sincerely
Prozento

Go for the 27Won catted. It is not a bottleneck.
There are no consequences for doing this.

I can't imagine the sound being rice. May be too quite for you as it is for most here. I still have stock front pipe and exhaust. PRL 3" downpipe. No issues and quiet. And still quick enough when I want to put the hammer down (EX-T CVT).
 

Anger

Senior Member
First Name
Nick
Joined
Sep 24, 2018
Threads
4
Messages
380
Reaction score
227
Location
Greece
Vehicle(s)
FK7,RW2,RD1,RD5,RE5,RU1,FK1,FN2,EP3
Vehicle Showcase
1
Country flag
There's a box to tick to disable this sensor. The bottom box p0138. I ran rv6 catted and front and it sounded different. Then invidia R400 and it sounds and runs great. I don't like the sound of just the dp enough but it is better than wisper quiet stock. I recommend the Rv6 but you also probably can't go wrong with the prl or 27won and they're all the same price. Also for install I went up from the bottom instead of taking turbo inlet off. And for 200 vs 300 cell they should pass emissions provided they're hot before the test.
upload_2019-3-30_22-24-4.png

Well, unfortunately I do not have any of these options. As said before, I have initial support. Initial support differs depending on what Ktuner has unlocked for each ECU. I hope that soon I will get at least the error disabling option so I can install the downpipe.

Talked to my tuner and he opted for the catted version as well. He did mention however that a non catted downpipe will not be an issue for emissions tests, as he can program the car at idle and 2500rpm accordingly.

@Myx how come suggest the 27WON over PRL which you own? Is it because of the smaller cat or is it something else?
 

bbeem

Senior Member
First Name
Ben
Joined
Nov 10, 2018
Threads
38
Messages
1,131
Reaction score
617
Location
Iowa
Vehicle(s)
19 si sedan, FZ1, CR450R, Shadow 750
Vehicle Showcase
1
Country flag
Oh that makes sense, I didn't realize what "initial support" was. I've also read here this civic can pass emissions catless if everything is up to temp. Regardless, once you replace the jamnuts with proper nuts changing back will be simple. I think the Rv6, prl, or 27won are all good choices. Megan seems like a good cheap cattless. I can speak for the Rv6 and it has a bottom clamp to fit stock front pipe or their 3" front pipe. I don't know what the others manufactures are doing for this. The #1 restriction is the OEM downpipe. After that it's pretty free flowing. The suitcase mufflers are the next restriction but they really aren't bad. Finally increasing the diameter of the connecting pipe but it really doesn't matter, especially if you have stock res back.
 

Myx

Senior Member
Joined
Mar 6, 2016
Threads
79
Messages
2,166
Reaction score
2,042
Location
Delaware
Vehicle(s)
2018 Honda Civic EX (Hatchback/CVT)
Vehicle Showcase
1
Country flag
@Myx how come suggest the 27WON over PRL which you own? Is it because of the smaller cat or is it something else?
Sent you a PM.
Sponsored

 


 


Top