DIY Full-Race 3" Downpipe and Catback Exhaust System

Scornio

Well-Known Member
252
69
Texas, Midland
Vehicle Model
Civic Si
Body Style
Sedan
I just installed my FR catless DP!! Hey @squiggy how bad is this rasp/ hiss supposed to be though? When I first fired it up I heard it right away sounded like there was a leak or something then once the car heated up it went away and I couldn't find the rpm pint where it was making the sound. Well when I drive that hiss and rasp or whatever it is is very loud? I'm guessing it's supposed to be?
 

squiggy

Cartographer
Super Mod
11,183
6,654
Michiana
Vehicle Model
'12 Civic Si
Body Style
DBP II Coupe
I just installed my FR catless DP!! Hey @squiggy how bad is this rasp/ hiss supposed to be though? When I first fired it up I heard it right away sounded like there was a leak or something then once the car heated up it went away and I couldn't find the rpm pint where it was making the sound. Well when I drive that hiss and rasp or whatever it is is very loud? I'm guessing it's supposed to be?
You need a tune...
 

Scornio

Well-Known Member
252
69
Texas, Midland
Vehicle Model
Civic Si
Body Style
Sedan
You need a tune...
I thought you would say that lol well ok it's next on my things to do! Well I was wondering should I get a PRL short ram/cold air intake? Or should I just do the resonator delete before I get a tune? As in which would benefit out of the 3?
 

squiggy

Cartographer
Super Mod
11,183
6,654
Michiana
Vehicle Model
'12 Civic Si
Body Style
DBP II Coupe
I thought you would say that lol well ok it's next on my things to do! Well I was wondering should I get a PRL short ram/cold air intake? Or should I just do the resonator delete before I get a tune? As in which would benefit out of the 3?
Either intake would be fine. You will get a few more horses from the CAI. I am running the SRI because I didn't want to deal with the battery relocation...and it was cheaper.
 

Scornio

Well-Known Member
252
69
Texas, Midland
Vehicle Model
Civic Si
Body Style
Sedan
Either intake would be fine. You will get a few more horses from the CAI. I am running the SRI because I didn't want to deal with the battery relocation...and it was cheaper.
Yea I was thinking of doing the same and also running the risk of hydrolocking. I know it's pretty hard for that to happen but where I'm at our drainage systems in town sucks so when it rains here it pours and our roads are flooded higher than the curbs. But would the SRI be any better than the stock intake w the resonator delete? Or would it just be a nice piece under the hood.
 

squiggy

Cartographer
Super Mod
11,183
6,654
Michiana
Vehicle Model
'12 Civic Si
Body Style
DBP II Coupe
Yea I was thinking of doing the same and also running the risk of hydrolocking. I know it's pretty hard for that to happen but where I'm at our drainage systems in town sucks so when it rains here it pours and our roads are flooded higher than the curbs. But would the SRI be any better than the stock intake w the resonator delete? Or would it just be a nice piece under the hood.
The PRL SRI has been proven to make some power.
 

twister8008

Well-Known Member
860
480
Omaha, NE, but I am a Wisconsinite
Vehicle Model
Civic SI
Body Style
Coupe
My intake, 3.5" Injen True CAI added about 5-7 HP to the wheels based my numbers with Vit. It requires a tune and a battery relocation. The new location is very similar to the old location in the front, but it uses a different bracket to make room for the tubing.
 

squiggy

Cartographer
Super Mod
11,183
6,654
Michiana
Vehicle Model
'12 Civic Si
Body Style
DBP II Coupe
My intake, 3.5" Injen True CAI added about 5-7 HP to the wheels based my numbers with Vit. It requires a tune and a battery relocation. The new location is very similar to the old location in the front, but it uses a different bracket to make room for the tubing.

Sounds like it is right in line with the PRL CAI. Glad to hear Injen corrected the catastrophe that was their first attempt at a CAI for a 9th Si.
 

twister8008

Well-Known Member
860
480
Omaha, NE, but I am a Wisconsinite
Vehicle Model
Civic SI
Body Style
Coupe
Sounds like it is right in line with the PRL CAI. Glad to hear Injen corrected the catastrophe that was their first attempt at a CAI for a 9th Si.

Yeah, the pictures of that CAI made it look like a choke artist with all of its twists and turns. This one is just a broad, straight 3.5" tube with a slight bend down to my fog light.
 

Scornio

Well-Known Member
252
69
Texas, Midland
Vehicle Model
Civic Si
Body Style
Sedan
Ahhh I don't know what to do!! Lol I want cold air but then I don't cause of hydrolocking but then I want the short ram too!!:( we'll see haha
 

Sarcras

Well-Known Member
1,133
702
North Dakota
Vehicle Model
Civic Si
Body Style
FB6
Ahhh I don't know what to do!! Lol I want cold air but then I don't cause of hydrolocking but then I want the short ram too!!:( we'll see haha
There are hydrophobic covers that you can put on the filters that repel water and keeps it from getting into the filter. They are not suppose to restrict any airflow into the filter either and they are pretty cheap.
 

Scornio

Well-Known Member
252
69
Texas, Midland
Vehicle Model
Civic Si
Body Style
Sedan
H
There are hydrophobic covers that you can put on the filters that repel water and keeps it from getting into the filter. They are not suppose to restrict any airflow into the filter either and they are pretty cheap.
Ok il have to look into that. It's really hard to chose though cause both have their pros and cons you know.
 

MadMike

Well-Known Member
42
40
Inland Empire, California
Vehicle Model
Civic SI
Body Style
Sedan
Just got my FR downpipe today. I noticed it didn't come with a gasket that mates to the head. Does it suppose to come with one? Or is reusing the stock one ok. I did notice stock one is smaller than the downpipe opening. Any help is appreciated.
 

r18-power

Well-Known Member
1,273
1,410
FL
Vehicle Model
Focus ST
Body Style
Hatchback
Yeah they don't come with one you are supposed to use the stock one, it will be fine that's what I did or you can buy one on ebay.
 

MadMike

Well-Known Member
42
40
Inland Empire, California
Vehicle Model
Civic SI
Body Style
Sedan
Thanks for this write up. I was in the process of taking everything apart this morning, When I got to the bottom to undo lower O2 sensor. I noticed I had oil sipping from somewhere. Looks like it's the passenger side driveshaft. The piece you can see in step 8 of your write up. Anyways have to put everything back to drop off at the dealer. Really was looking forward to installing downpipe so I can begin to tune.
 

Tim Abadie

Well-Known Member
84
76
Jupiter, FL
Vehicle Model
FB6
Doing this install tomorrow. Quick question, as far as the exhaust goes, would this DIY apply to the sedan version of the exhaust as well?
 
Top