Turbo Back Exhaust - Insanely Loud Cold Start?
 

I have an ultimate racing catted DP, with a CS test pipe and catback exhaust, fully tuned. My cold start in my underground parking literally triggers car alarms. Overall it sounds healthy, but the extreme noise lasts for about 15 - 20 seconds at 2k rpm.

Is this normal or can it be tuned out?

You can bypass the cold start by blipping the throttle as you turn the motor over. It will also be very loud, but only last as long as the blip.

This^ my neighbors wanted to call the cops on me because of my exhaust. I just do what wetz told me and so far I haven't seen any cops waiting for me to start it.

And @Djohns; exhaust is loud as fuck. Surprised the hell out of me that it was comparable if not louder than my car with less exhaust flow than I have.

Tis' true. Scares me for when the s4 goes in.

Out of curiosity, does anyone know what causes this amount of noise on a cold start, and why a 'throttle blip' makes it go away?

ECU logic puts the car into open loop on a cold start in order to bring it up to operating temperature faster. Blipping the throttle bypasses this and lets the car go into closed loop right away, reducing cold start idle to normal operating temp idle.

Welcome to the club, this is why I push my car out of the garage and roll it to the end of the driveway before starting it at 5:30 in the morning with sleeping wife and kids. I live in a rural area so I've never had any neighbors complain. Thanks for the tip @WetzMS3;on blipping the throttle at start though, I'll definitely be trying that out tomorrow morning. I would think a larger turbo turbine (i.e. BNR S4) would help quiet the exhaust some by consuming more energy to move the rotating assembly and thus reducing the sound energy left over, but I could be wrong. This is just my inclination as my car is much louder than my friends big turbo integra, well for the exception of when his wastegate is open.

3" catless turboback here, talk about insanely loud cold start. Thankfully I only have 1 neighbor who runs his lawn equipment the same time I leave and my wife works the same hours as me, or else Id be screwed.

I wasn't necessarily pointing at my larger turbo being the increased exhaust flow compared to David. That's just one piece of the puzzle. In my experience, tubular exhaust manifold created the largest increase in volume on my car. I think David's mufflers just create an oddly, extremely loud sound. I wouldn't be surprised if his exhaust is slightly more restrictive than mine, even though it is louder.

Just spit balling here. Other than the tubular mani causing a huge increase in sound. Full Race, FTW.

I question if there's anything in my mufflers or if they're just for show. Bought it custom second hand so it's all a mystery.

Based on the grumbliness of your exhaust I am assuming there is some baffling in there. Spit-balling, like I said. I know the UR exhaust on my car is one of, if not the least restrictive muffler on OTS exhausts. The sound of your exhaust really seems to create noises that the motor doesn't make naturally, if that makes any sense, lol.

We could always make you straight pipped and cut open those mufflers!! For science.

That would be a science lesson followed by many tickets and pissed off neighbors.

I wonder if "For Science" is a valid excuse to get out of tickets??

I would assume that depends on the officer and his/her current mood.

That's just the way it is, hi flow bigger exhaust are noisy, and if its an everyday car, its either you or your neighbours will get sick of it not to mention the cops will love you.
If it is a concern, I would start looking for other exhaust set up that is more silent.

Search Varex mufflers

Bruh

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OK I'll bite, you wouldn't happen to have a vid of your exhaust would ya? I need to hear this freak of nature.

Sent using smoke signals

The throttle blip fixed my issue. One loud blast is better than a 20 second space shuttle launch. Thank you.

....Buys obnoxiously loud exhaust system.

...then complains that it's obnoxiously loud.

;)

I don't find it obnoxiously loud other than the cold start. When I bought the car used I didn't say, "I hope it's loud when I start it, but that's the only time".

;)

Only exhaust mod for me is the gutted second cat; my neighbors couldn’t believe it was stock exhaust... blipping the throttle is the way to go.

Isn't it ironic?

Back in "the day", we used to blip the throttle to set the choke and get 1 squirt out of the accelerator pump so the car will run cold.
Then this fancy electronic fuel injection comes along, and now the carputer does it for us....almost flawlessly.
Now, I'm blipping the throttle again to avoid the high revs on a cold start. I don't wanna burn the extra fuel or let my engine rev cold, and I don't wanna wake my kids who sleep in the room right next to the garage.

I typically just press the accel pedal about 10% while cranking the key, and as soon as it starts to fire up, let off. You can do it with a loud "blip" but it takes the correct timing. I wish we could just disable that cat warm-up procedure in ATR. Maybe its a feature we can ask for in Versatune?

I do but I have no clue how to upload videos.

just so you guys know.... the idle tables have values for different ect. u can bring down the rpms it is reving too. I also found out on some cars this doesn't work. so under load max a,b tables for 500,1000,1500 rpm u can lower the load there and get the same results 500=.50 1000=.60 and 1500=.70 try that.

English is not my native langage...what do you guys do when you say "Blip the throttle" ?

rev the gas pedal

Hold the gas petal down slightly while starting the car then letting off upon the car starting.

Thanks!