Help: The best diameter DP/FP for my setup

Hondanickx

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im hoping a large 300cpsi cat will reduce the cold 1start up noise more than it does on the 27won dp/fp i have heard on youtube they are pretty loud! i also have an ARK exhaust so im aware it wont be as quiet if it was paired with stock. i have enquired to see if they will ever sell the cat on its own as im not too bothered about the frontpipe. it would be nice to know if it would just bolt onto oem frontpipe but i think that would create a serious bottleneck would you say?

oh thats a bonus if it helps you guys with emissions, to be honest i thought most catted downpipes were efficient for emissions tests hence why they made catted versions and not just race versions?

Wagner has a installation instructions file on their website where you can see you can choose either the stock front pipe or their 3 inch front pipe .So yes it will also bolt onto the oem front pipe.
install PDF file
It will create a bottleneck offcourse yes .It would be nice if they sold the downpipe seperatly ,as i like to use my own front pipe as wel.The only thing that i don"t like is the gasket they use to connect the downpipe with the front pipe.I would have changed that so something more durable like a v band or a crush seal.They did enlarged the oem style flange and added a extra mounting hole for their 3inch downpipe flange.

Honda Civic 10th gen Help: The best diameter DP/FP for my setup wagner tuning downpipe install
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varge

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Had this custom piece made for me at a workshop here in Greece. DP is 3" tapering to 2.5" before the FP and FP is tapered to 2" to match the rest of the stock exhaust. Very pleased with the results, and has only added some "tone" to the exhaust sound, certainly no noise at all. Also didn't need to disable the Secondary O2 sensor, no CEL whatsoever.

Honda Civic 10th gen Help: The best diameter DP/FP for my setup 1614978762050
 

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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
 

CIVICUK

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Had this custom piece made for me at a workshop here in Greece. DP is 3" tapering to 2.5" before the FP and FP is tapered to 2" to match the rest of the stock exhaust. Very pleased with the results, and has only added some "tone" to the exhaust sound, certainly no noise at all. Also didn't need to disable the Secondary O2 sensor, no CEL whatsoever.

1614978762050.png
that looks so good! what catalyst size did they use? it looks like a 200 cpsi and the welds is very neat and a huge bonus you dont get any CEL code (even though your ktuner can disable it)

how much did it cost if you dont mind me asking george?
 

CIVICUK

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Wagner has a installation instructions file on their website where you can see you can choose either the stock front pipe or their 3 inch front pipe .So yes it will also bolt onto the oem front pipe.
install PDF file
It will create a bottleneck offcourse yes .It would be nice if they sold the downpipe seperatly ,as i like to use my own front pipe as wel.The only thing that i don"t like is the gasket they use to connect the downpipe with the front pipe.I would have changed that so something more durable like a v band or a crush seal.They did enlarged the oem style flange and added a extra mounting hole for their 3inch downpipe flange.

wagner tuning downpipe install.jpg
thank yo so much for this i could not see this on their website and its helped answer my questions in regards to the install.

i do think this is very pricey as a kit and i would feel safer if they used V-band clamps like you say to prevent any leaks. if the front pipe does not help carry any engine noise towards the catback then i will happily install their frontpipe so at least it goes to my 2.5" piping so its not too much of a bottle neck but i have always had this theory that the enlarged frontpipes carry the engine noise and not reducing it if that makes sense? im no expert ive just always liked the idea of keeping my frontpipe and catback system between 2-2.5" diameter.
 


varge

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that looks so good! what catalyst size did they use? it looks like a 200 cpsi and the welds is very neat and a huge bonus you dont get any CEL code (even though your ktuner can disable it)

how much did it cost if you dont mind me asking george?
It was 650€ including the FP and I'm pretty sure it is 300cpsi.
I know I can disable it, but no CEL is a good thing, I suppose.
 

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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).
Do you like the 27won dp with oem exhaust ? do you think its slightly limiting it or due to the restrictive exhaust ?
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