5" Exhaust work alright with a stock turbo? - Diesel Truck Forum - TheDieselGarage.com
Thread Details Posted by mac325, this thread has received 16 replies and been viewed 1716 times.

Reply
 
LinkBack Thread Tools Display Modes
post #1 of 17 (permalink) Old 06-26-2007, 03:34 PM Thread Starter
 
Join Date: Jun 2007
Posts: 10
Points: 1,203
Thanks: 0
Thanked 0 Times in 0 Posts
5" Exhaust work alright with a stock turbo?

I was read in a magazine that a 5" exhaust with a stock turbo will hurt your performance.They said it had something to do with the loss of boost pressure and the engine electrionics compensating for that loss. I am not sure, but a little worried since I have a 5" being installed in my truck tomorrow! Any insight on this.

Mac:shrug:
mac325 is offline  
Sponsored Links
Advertisement
 
post #2 of 17 (permalink) Old 06-26-2007, 03:52 PM
Senior Member
 
sstockton's Avatar
 
Join Date: Jan 2009
Posts: 3,514
Points: 69,214
Thanks: 3
Thanked 64 Times in 60 Posts
It will hurt it a little bit, but not really that much. You really don't need to run a 5inch exhaust until you are in the 500+ hp range. Yes you will actually lose a little performance, but honestly, its such a small amount it shouldn't be noticable, IMO. I have a couple friends that put them on unmoddified Common Rails, and actually lost about 1.5mpg in doing so. I'm not sure what you'd lose with a vp44 24v though.
Sean

2000 2500 reg. cab 4x4 auto 577hp
09 6.7L QC LB stick, 4x4.

TOTAL PERFORMANCE DIESEL 707-545-FUEL (3835)
www.totalperformancediesel.com
sstockton is offline  
post #3 of 17 (permalink) Old 06-26-2007, 05:24 PM Thread Starter
Threadstarter
 
Join Date: Jun 2007
Posts: 10
Points: 1,203
Thanks: 0
Thanked 0 Times in 0 Posts
OK, thanks! My old exhaust was a thrown together mess of patches from the previous owner. I plan of future mods, hopefully, approaching the 450 mark. I had been told this was the "cutoff" for 4" and 5". So I figured while I needed the exhaust might as well get the 5", and have it done. Plus I love the sound:bow: !

Thanks again,

Mac
mac325 is offline  
post #4 of 17 (permalink) Old 06-26-2007, 06:43 PM
Senior Member
 
sstockton's Avatar
 
Join Date: Jan 2009
Posts: 3,514
Points: 69,214
Thanks: 3
Thanked 64 Times in 60 Posts
Yeah, if you're going to continue modding the truck then you might as well do the 5inch now. Instead of doing it agian later down the road. Plus they do sound wicked.
Sean

2000 2500 reg. cab 4x4 auto 577hp
09 6.7L QC LB stick, 4x4.

TOTAL PERFORMANCE DIESEL 707-545-FUEL (3835)
www.totalperformancediesel.com
sstockton is offline  
post #5 of 17 (permalink) Old 06-27-2007, 01:50 AM Thread Starter
Threadstarter
 
Join Date: Jun 2007
Posts: 10
Points: 1,203
Thanks: 0
Thanked 0 Times in 0 Posts
Yeah, thats what I thought. My only problem is I know just about enough to be dangerous with these diesels, : . I just got kind of worried when I read that article, I thought, "Oh, boy did I screw up...how much power am I going to lose". I am really glad I found this site, a lot of good info so far.

Thanks,

Mac
mac325 is offline  
post #6 of 17 (permalink) Old 06-27-2007, 02:30 PM
Bouncer
Guest
 
Posts: n/a
Points: 0 [Check]
IMO, there is not enough difference in the 4" to 5" exhaust to justify the money if you are at 450hp or 550hp. If you like the sound then get it by all means, but just remember it is still 4" at the downpipe.
post #7 of 17 (permalink) Old 06-27-2007, 06:37 PM
 
Join Date: Jan 2007
Posts: 216
Points: 2,546
Thanks: 0
Thanked 0 Times in 0 Posts
i run 5 inch on my truck and i dont notice anything.
bada$$dodge2000 is offline  
post #8 of 17 (permalink) Old 06-27-2007, 10:29 PM Thread Starter
Threadstarter
 
Join Date: Jun 2007
Posts: 10
Points: 1,203
Thanks: 0
Thanked 0 Times in 0 Posts
Well, got it on today. I don't notice any difference in power, in fact I think it runs a little better. Guess that goes to show you can't believe everything you read, lol. The sound is awesome, and the guy did a primo job on the install. He welded it all and they are some pretty welds. The kit he got in came with a muffler and no tip, so he traded me a tip for the muffler I wasn't going to use.

Very happy:Thumbup: ,

Mac
mac325 is offline  
post #9 of 17 (permalink) Old 06-28-2007, 12:12 AM
 
Join Date: Dec 2008
Posts: 2,189
Points: 44,835
Thanks: 0
Thanked 0 Times in 0 Posts
No way, how does a turbo charged engine ever run into backpressure issues after the turbo? In all of engine theory, gas or diesel I've never heard that before. Never have I heard that.




EDIT: I had stock, 4inch, and 5 inch. The difference between 4 or 5 was nothing but sound. The MPG jumped up from stock though. Owner Operater trucks don't run 7 to 8 inch exhaust because it sounds good, but hurt MPG.
Smokem is offline  
post #10 of 17 (permalink) Old 06-28-2007, 02:04 AM Thread Starter
Threadstarter
 
Join Date: Jun 2007
Posts: 10
Points: 1,203
Thanks: 0
Thanked 0 Times in 0 Posts
Philly,

This is just what I happened to read in the Diesel World magazine I picked up at Wally World the other day. In the Tech Matters section someone wrote in about be told you will loose power when using a 5" exhaust with a stock turbo and this was the magazines response:

"You heard right about the larger exhaust and the need for a turbo upgrade. The general consensus is: a larger diameter exhaust system affects turbo response time (boost pressure lag). These electronic diesels monitor boost pressure, and calculate fueling based on that boost pressure. A lazy turbocharger will ultimately effect how much fuel is delievered, possibly resulting in a loss of performance after installing a 5" exhaust system."

Like I said before I was just a little worried when I read this, because I am no expert when it comes to diesel engines. I have noticed no performance drop at all with my truck, in fact I think it runs much better than it did before. Time will tell on the MPG gain, if I can keep my foot out of it.

Thanks,
Mac
mac325 is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Diesel Truck Forum - TheDieselGarage.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may 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 On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome