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Discussion Starter · #1 ·
Quick question for you all. Have a 16 RS with JB4 on map 6, running 4.5 lbs of boost max tapering up and down. Looking for a little more. I don't want to start doing exhaust mods, would adding a HPFP add anything to performance without changing exhaust?
 

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My advise is get all the supporting mods first. Make a plan.
 

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My advise is get all the supporting mods first. Make a plan.
Agreed. You need to make more power before reaching the flow limits of the stock HPFP.

For reference, with my mods (see signature), my Q60 made 437 WHP/502 WTQ on a Dynojet AWD dyno. I'll be adding an AMS HPFP to the mix, but on pump gas, I can only expect to pick up (likely) 20-30 WTQ in the low to midrange rpms with a modification to my Ecutek tune (to account for the higher flow rate of the pump).

At this stage of your build, a better HP & TQ investment is LDPs & CBE vs HPFP for nearly the same $.
 

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Mods are cumulative.
#1 Downpipes (full or LDP) and good CBE
#2 bigger Heat exchanger
#3 tune
#3b lighter rims and brake rotors

With more power better brake pads may be a VERY good idea.
See how those go.. then start looking at pumps and turbos & injectors. That's where I am now.
 

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Discussion Starter · #5 ·
Thanks for the replies. My fear is a drone with exhaust change. I absolutely hate loud exhaust or a drone at highway speed. Am I stuck?
 

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Thanks for the replies. My fear is a drone with exhaust change. I absolutely hate loud exhaust or a drone at highway speed. Am I stuck?
I plan to just swap the Y and Midpipe and keep the stock muffler. Already have AMS downpipes. Hoping this will keep the tone civil. I believe @Ddnspider has this same exhaust setup, but I haven't heard any video clips yet
 

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Thanks for the replies. My fear is a drone with exhaust change. I absolutely hate loud exhaust or a drone at highway speed. Am I stuck?
The FI CBE, paired with either its LDPs or the catted DPs, is drone-free on the highway. As I've commented before, it passes the wife test. You will only notice some drone when in a low-rev condition when the engine is under load, such as going up a hill. Other than that, the road noise from the DumFlats is more intrusive into the cabin than the exhaust.

BTW, FI calls the current CBE (non-resonated or resonated) its "Touring" edition. Some customers have asked for even more "bark", and I'm told an optional muffler (louder) is under development.
 

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Thanks for the replies. My fear is a drone with exhaust change. I absolutely hate loud exhaust or a drone at highway speed. Am I stuck?
I plan to just swap the Y and Midpipe and keep the stock muffler. Already have AMS downpipes. Hoping this will keep the tone civil. I believe @Ddnspider has this same exhaust setup, but I haven't heard any video clips yet
cold start is the loudest and it's still not bad with the windows up. Cruise and warm idle is still real quiet. Has a growl with more throttle.
 

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Just make sure to get the resonated X-pipe if you want it quieter. Keven at FI recommends it with the full downpipes. He talked me into it. I'm so glad he did! I absolutely LOVE the way it sounds.
At the post office one day an older lady, 80+ said with a twinkle in her eye, "That's the way a car should sound!" Surprised the heck out of me. I smiled big time and replied "Why thank you, I agree."
 

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cold start is the loudest ..
Agreed. From my understanding, depending on the ambient temperature, the ECU will bump up the cold idle speed to achieve closed loop faster, to "light-off" the primary cat. I also believe the wastegates are cycled open to increased the exhaust flow to the primary cat.
 
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I don't know exactly why, but cold start it pretty loud out here in the sticks. I remote start my car with the garage door closed. By the time I'm buckled up, situated, and open the garage door with my mirror button, the cold start cycle quits. Unless it's really cold out. That way my neighbors are not disturbed.

I have very little ambiant noise at my place. My bullfrogs or peepers in my pond are about it. My driveway is 650' long.
 

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Agreed. From my understanding, depending on the ambient temperature, the ECU will bump up the cold idle speed to achieve closed loop faster, to "light-off" the primary cat. I also believe the wastegates are cycled open to increased the exhaust flow to the primary cat.
I think the noise is mainly the wastegates being open. Bypassing the turbo's as mufflers is going to make some noise lol. But as soon as you put it in gear it gets quiet. Also, here's a sound/vid clip:
https://youtu.be/_jc8fDZbtsw
 

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I think the noise is mainly the wastegates being open. Bypassing the turbo's as mufflers is going to make some noise lol. But as soon as you put it in gear it gets quiet. Also, here's a sound/vid clip:
https://youtu.be/_jc8fDZbtsw
Very manageable tone, thanks for uploading. Didn't you get the Tanabe midpipe?
 

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Very manageable tone, thanks for uploading. Didn't you get the Tanabe midpipe?
Yes sir. Took longer than expected to get but believe they got a big shipment in, at least who I ordered from. Install was very straightforward and fitment was excellent.
 

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I don't know exactly why, but cold start it pretty loud out here in the sticks. I remote start my car with the garage door closed. By the time I'm buckled up, situated, and open the garage door with my mirror button, the cold start cycle quits. Unless it's really cold out. That way my neighbors are not disturbed.

I have very little ambiant noise at my place. My bullfrogs or peepers in my pond are about it. My driveway is 650' long.



wait a sec.... you have your car running in a closed garage?
 

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Yes sir. Took longer than expected to get but believe they got a big shipment in, at least who I ordered from. Install was very straightforward and fitment was excellent.
Misread your caption on the video, it does mention it. Car sounds perfect. Looking forward to adding those pipes and BOVs
 

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wait a sec.... you have your car running in a closed garage?
Yes, for 3 minutes, but open the door when I first step into it. NBD. It keeps most of the cold start noise contained.
 

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Speaking of the AMS HPFP, just ordered it from CZP - sale priced @ $100 off and no tax. :)
 

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I don't know exactly why, but cold start it pretty loud out here in the sticks. I remote start my car with the garage door closed. By the time I'm buckled up, situated, and open the garage door with my mirror button, the cold start cycle quits. Unless it's really cold out. That way my neighbors are not disturbed.

I have very little ambiant noise at my place. My bullfrogs or peepers in my pond are about it. My driveway is 650' long.
Why worry about noise if you're out in the sticks John? Worried about waking the owls? ;)
 

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One house is only 50 yards away. My 6.25 acre lot is a long rectangle so one is fairly close, one other is at the end of my driveway with a new born. Being so quiet and my property open in that direction I try to be considerate. Sound travels and it reflects off my pond which has a hill behind it.
 
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