New to Forum, Question - Mustang Evolution

Go Back   Mustang Evolution > 1979-2015 Mustang GT || Tech and Talk > 2011-2014 Mustang GT



Reply
 
Thread Tools Search this Thread
Please support our sponsors and let them know you heard about them here!
Old 03-23-2015, 03:51 PM   #1
Registered Member
Regular
 
christianh's Avatar
 
Join Date: Mar 2015
Location: Cape Coral
Region: Florida
Posts: 89
New to Forum, Question

Hey Everyone,

I have viewed countless questions and answers in Mustang Evolution and figured it was time to join. I'm sure I'll be posting and reading quite a few threads as I am building my ride.

I had a question regarding exhaust. I currently have Roush axlebacks as my only "performance" mod. Everything else is stock. Not with cold starts, that's different, but after the motor has warmed up and the car is sitting idling, the volume of the idle will change periodically from soft to loud. It's almost like a valve is being opened and closed muffling and un-muffling the sound. I've tried turning of the AC (I live in Florida) and it makes no difference.

Does anyone know what this is?

Thanks
christianh is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 03-23-2015, 04:49 PM   #2
Registered Member
Regular
 
The_Chech's Avatar
 
Join Date: Apr 2014
Location: Charlotte
Region: North Carolina
Posts: 976
Guessing just the amount of exhaust gasses are inside all the piping at a given moment would cause it to change periodically. As some times it may have less gas to push out some times.


Sent from my iPhone using Mustang Evolution
__________________


Oxford White Roush Stage 1 SN# 6925--SOLD but never forgotten!
Kona Blue GT premium - Slammed on BC's and BMR's full rear suspension
The_Chech is offline   Reply With Quote
Old 03-23-2015, 05:30 PM   #3
Registered Member
Regular
 
christianh's Avatar
 
Join Date: Mar 2015
Location: Cape Coral
Region: Florida
Posts: 89
Ok, was just wondering if it was a common known thing. I think some cars have an electronic type of valve that can change the volume that can be removed. Was curious if this was the case
christianh is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 03-24-2015, 02:48 PM   #4
Registered Member
Regular
 
Join Date: Mar 2015
Location: Detroit
Region: Michigan
Posts: 32
Are the RPMs changing in addition to the volume? I'm guessing the answer is yes, at that is really the only reason the "volume" should be changing. If that's the case, and you're RPMs are just fluctuating while sitting still, you may have other issues. Is the car tuned?
Just_A_GT is offline   Reply With Quote
Old 03-24-2015, 02:49 PM   #5
Registered Member
Regular
 
Join Date: Sep 2014
Location: Austin
Region: Texas
Posts: 110
I'd need to hear what you're talking about. Does your idle change when the exhaust sounds does? If I had to guess it would be that since the car is in closed loop idle it's making a noticeable timing adjustment to meet the target idle revolution.

Sent from my SM-N900T using Mustang Evolution mobile app
__________________
2012 GT (Brembo)
MGW Race spec
Steeda Sports
Koni STR's
Air Raid CAI
Borla axlebacks
ShatterPoints is offline   Reply With Quote
Old 03-24-2015, 02:51 PM   #6
Registered Member
Regular
 
Jbone007's Avatar
 
Join Date: Mar 2015
Location: Oceanside
Region: California
Posts: 435
Who did your exhaust? I would have them check it, that doesn't sound normal to me! At least I have not noticed it on my car!
Jbone007 is offline   Reply With Quote
Old 03-24-2015, 02:53 PM   #7
Registered Member
Regular
 
christianh's Avatar
 
Join Date: Mar 2015
Location: Cape Coral
Region: Florida
Posts: 89
I did it myself, then had a family friend who owns a shop check it for me. Said it was good. One of those hard to describe things


Sent from my iPhone using Mustang Evolution
__________________
Paxton Charged Unicorn
christianh is offline   Reply With Quote
Old 03-24-2015, 02:54 PM   #8
Registered Member
Regular
 
Join Date: Sep 2014
Location: Austin
Region: Texas
Posts: 110
I'd still say it's normal closed loop idle.

Sent from my SM-N900T using Mustang Evolution mobile app
__________________
2012 GT (Brembo)
MGW Race spec
Steeda Sports
Koni STR's
Air Raid CAI
Borla axlebacks
ShatterPoints is offline   Reply With Quote
Old 03-24-2015, 02:56 PM   #9
Registered Member
Regular
 
christianh's Avatar
 
Join Date: Mar 2015
Location: Cape Coral
Region: Florida
Posts: 89
Quote:
Originally Posted by ShatterPoints View Post
I'd need to hear what you're talking about. Does your idle change when the exhaust sounds does? If I had to guess it would be that since the car is in closed loop idle it's making a noticeable timing adjustment to meet the target idle revolution.

Sent from my SM-N900T using Mustang Evolution mobile app

I think you're exactly on the money. Been doing more research and that's kind of what it sounds like. The RPMs fluctuate slightly, maybe a 100. And no, car Is not tuned


Sent from my iPhone using Mustang Evolution
__________________
Paxton Charged Unicorn
christianh is offline   Reply With Quote
Old 03-24-2015, 03:02 PM   #10
Registered Member
Regular
 
Join Date: Sep 2014
Location: Austin
Region: Texas
Posts: 110
Well its factory tuned. So there is a target idle speed. I'm not sure the resolution for the spark table in the ecm. Though you may only see it change a little bit, it's probably the result of change in spark. It could even be a trim for ignition Dwell.

Sent from my SM-N900T using Mustang Evolution mobile app
__________________
2012 GT (Brembo)
MGW Race spec
Steeda Sports
Koni STR's
Air Raid CAI
Borla axlebacks
ShatterPoints is offline   Reply With Quote
Old 03-24-2015, 03:02 PM   #11
Registered Member
Regular
 
Jbone007's Avatar
 
Join Date: Mar 2015
Location: Oceanside
Region: California
Posts: 435
Could be the Closed loop idle that that ShatterPoints has suggested, will pay a little closer attention to mine and see if I notice that issue, you should not need a custom tune with just a Roush axlebacks but it would not hurt!
Jbone007 is offline   Reply With Quote
Old 03-24-2015, 03:49 PM   #12
Registered Member
Regular
 
christianh's Avatar
 
Join Date: Mar 2015
Location: Cape Coral
Region: Florida
Posts: 89
Quote:
Originally Posted by Jbone007 View Post
Could be the Closed loop idle that that ShatterPoints has suggested, will pay a little closer attention to mine and see if I notice that issue, you should not need a custom tune with just a Roush axlebacks but it would not hurt!

Agreed!

I would be willing to order a CAI and tune right now, I think they really help. But I'm in this dilemma:
Idk if I will be supercharging the car soon. Have been looking at different options. I'm not concerned about getting insane power, maybe an added 200hp. Roush stage one or two has been on my mind, but whipple is 10% off right now on lethal performance's site.

So in that case, ordering a CAI and tune wouldn't make much sense


Sent from my iPhone using Mustang Evolution
__________________
Paxton Charged Unicorn
christianh is offline   Reply With Quote
Old 03-24-2015, 04:39 PM   #13
Registered Member
Regular
 
Jbone007's Avatar
 
Join Date: Mar 2015
Location: Oceanside
Region: California
Posts: 435
Nice, I want to go that route also just waiting on some cash to free up, This is the one I have my eye on! Ford Racing 624HP Mustang Supercharger Kit - Polished Finish M-6066-MGT624PD (11-14 GT) - Free Shipping
Jbone007 is offline   Reply With Quote
Old 03-24-2015, 05:05 PM   #14
Registered Member
Regular
 
christianh's Avatar
 
Join Date: Mar 2015
Location: Cape Coral
Region: Florida
Posts: 89
Love it. I'll admit I'm trying to teach myself about superchargers, not very familiar with them and I've never driven one. But what would the advantages be of the ford racing brand vs a roush one when the roush is cheaper? Just curious


Sent from my iPhone using Mustang Evolution
__________________
Paxton Charged Unicorn
christianh is offline   Reply With Quote
Old 03-24-2015, 05:15 PM   #15
Registered Member
Regular
 
Join Date: Sep 2014
Location: Austin
Region: Texas
Posts: 110
Quote:
Originally Posted by christianh View Post
Love it. I'll admit I'm trying to teach myself about superchargers, not very familiar with them and I've never driven one. But what would the advantages be of the ford racing brand vs a roush one when the roush is cheaper? Just curious


Sent from my iPhone using Mustang Evolution
The differences would be what's included in their kits. Next would be the type of supercharger, eg. centrifugal /roots /etc. Depending on what you choose each one will differ in air flow also.

Sent from my SM-N900T using Mustang Evolution mobile app
__________________
2012 GT (Brembo)
MGW Race spec
Steeda Sports
Koni STR's
Air Raid CAI
Borla axlebacks
ShatterPoints is offline   Reply With Quote
Old 03-24-2015, 08:15 PM   #16
Registered Member
Regular
 
hitmeagain's Avatar
 
Join Date: Jun 2014
Location: Wilkes
Region: North Carolina
Posts: 61
Mine does this weird idle thing same as op.... My mazdaspeed3 did it as well, mine only does it when cold and It sounds as if a large load is placed on engine a few seconds after start up and the exhuast becomes louder... I think it is tune related and helps the converters warm up more quickly?
hitmeagain is offline   Reply With Quote
Old 03-24-2015, 08:45 PM   #17
Registered Member
Regular
 
Join Date: Sep 2014
Location: Austin
Region: Texas
Posts: 110
Quote:
Originally Posted by hitmeagain View Post
Mine does this weird idle thing same as op.... My mazdaspeed3 did it as well, mine only does it when cold and It sounds as if a large load is placed on engine a few seconds after start up and the exhuast becomes louder... I think it is tune related and helps the converters warm up more quickly?
If its tuned and this happens, it's likely whoever tuned it either does not have the table resolution for proper idle. Or they just did a poor job tuning idle values. However this could also have to do with what hardware you're running vs how/what the car was tuned.

This is why canned tunes for example are more susceptible to issues, as the tuner is remote. While they get a good idea of what and how you're running they just don't have the whole picture.

Sent from my SM-N900T using Mustang Evolution mobile app
__________________
2012 GT (Brembo)
MGW Race spec
Steeda Sports
Koni STR's
Air Raid CAI
Borla axlebacks
ShatterPoints is offline   Reply With Quote
Old 03-24-2015, 08:51 PM   #18
Registered Member
Regular
 
hitmeagain's Avatar
 
Join Date: Jun 2014
Location: Wilkes
Region: North Carolina
Posts: 61
I'm on stock tune.... And engine is stock except for axle backs....
hitmeagain is offline   Reply With Quote
Old 03-25-2015, 08:35 AM   #19
Registered Member
Regular
 
christianh's Avatar
 
Join Date: Mar 2015
Location: Cape Coral
Region: Florida
Posts: 89
Quote:
Originally Posted by hitmeagain View Post
I'm on stock tune.... And engine is stock except for axle backs....
Perhaps it's the timing thing these guys mentioned. Sounds like we have the same set up.
christianh is offline   Reply With Quote
Old 03-25-2015, 09:19 AM   #20
Registered Member
Regular
 
Join Date: Sep 2014
Location: Austin
Region: Texas
Posts: 110
Hitme,

There could be numerous things which would cause that behavior. It's most likely normal in your case.

Sent from my SM-N900T using Mustang Evolution mobile app
__________________
2012 GT (Brembo)
MGW Race spec
Steeda Sports
Koni STR's
Air Raid CAI
Borla axlebacks
ShatterPoints is offline   Reply With Quote
Reply

Lower Navigation
Go Back   Mustang Evolution > 1979-2015 Mustang GT || Tech and Talk > 2011-2014 Mustang GT

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
New to Ford, New to Mustang, and New to Forum F4nG New Member Introductions & Greetings 3 06-11-2013 08:16 AM
New to the forum and have a question 04DSGM1 1996-2004 Mustang GT 10 10-28-2010 09:17 AM
new to the forum.. i have an opinion question 02whitemustang Mustang Wheels & Tires 12 05-10-2006 09:11 AM

» Like Us On Facebook



06:19 AM


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0

MustangEvolution.com is in no way associated with or endorsed by Ford Motor Company.