LS - 1st and 2nd Gen (1990-2000) Discussion topics related to the 1990 - 2000 Lexus LS400

more exhaust fun..

Thread Tools
 
Search this Thread
 
Old 09-04-02, 10:43 AM
  #1  
Lvangundy
Guest
 
Posts: n/a
Default more exhaust fun..

Well -- Yesterday I went and had the centor resonator removed (replaced with 2.5" pipe). I have pics but too lazy to post.

Yesterday it seemed considerably louder, but today it's not so noticeable. The thing that's frustrating is that I have no way of telling if doing all this to my exhaust system actually yields any benefits. It's like throwing money into someone else's hands and knowing about any return. I really would love some dyno time!

Looks like the only way I'm going to get that deep Greddy PE sound is to actually go and buy one. blah!

PS..my interior is quite comical right now. Worth a chuckle. All of the back seating and wall covers are removed. Retrodrive - I might be interested in that RAAMmat stuff. Getting the back seats recushioned and want too add some sound deadening material.
Old 09-05-02, 11:23 AM
  #2  
Lvangundy
Guest
 
Posts: n/a
Default

Does anyone know why I get that crackling backfiring noise from the exhaust when the car is cold? After it's warmed up completely (temp guage halfway) it doesn't make that noise anymore.

Someone told me the air fuel mixture isn't balanced, and someone thought it was a rattle.
Old 09-05-02, 03:28 PM
  #3  
retrodrive
Search Function Inc.
 
retrodrive's Avatar
 
Join Date: Jul 2001
Location: California
Posts: 4,819
Likes: 0
Received 2 Likes on 1 Post
Default

You need tar based products (like mat) to eliminate any panel flexing and rattling but to make your car quieter, use 1/8 and 1/4 inch foam all around the car. Mat does not have much insulating properties and I would only use it for audio plications. Man, just by an exhaust
Old 09-06-02, 05:42 PM
  #4  
JBrady
Lexus Champion
 
JBrady's Avatar
 
Join Date: Feb 2001
Location: Texas
Posts: 3,124
Received 31 Likes on 25 Posts
Default

Originally posted by Lvangundy
Does anyone know why I get that crackling backfiring noise from the exhaust when the car is cold? After it's warmed up completely (temp guage halfway) it doesn't make that noise anymore.

Someone told me the air fuel mixture isn't balanced, and someone thought it was a rattle.
Well, going with larger pipes increases the total volume of the system and slows the flow in the area. The extra volume alows for a more pronounced "rebound" or "spring" effect of the compressible gasses. Under acceration the gasses compress and during decelleration the gasses expand. This effect is like a bouncing ball. This creates a pulsation and pulls and pushes the gasses back and forth. Also, during decel, the engine goes rich and this unburned fuel goes into the exhaust. When hot the cats burn this but before they heat to operation temp they cannot and this mixture can pulse back into a flame front and explode, giving you a backfire(s).

On the Vettes, when they go with a higher flow system backfiring is often encountered. One of the ways they reduce/eliminate the problem is with an X pipe like I talk about in my exhaust thread.

Now, I just called L-tuned and they offer a system (if you can call it that) for the LS at a cost of $1200 :eek: :eek: :eek: and this is JUST for the rear mufflers ONLY :eek:

Last edited by JBrady; 09-06-02 at 05:44 PM.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
718murdoc
Performance & Maintenance
5
05-10-10 01:28 PM
justinp95
LS - 1st and 2nd Gen (1990-2000)
3
02-17-10 07:29 AM
T-Lex
Performance & Maintenance
3
01-26-07 12:16 PM
whosdady
Performance & Maintenance
10
12-25-01 06:40 AM
CamRen
GS - 2nd Gen (1998-2005)
3
10-17-01 12:40 PM



Quick Reply: more exhaust fun..



All times are GMT -7. The time now is 09:03 AM.