95.5-2004 Tacomas & 96-2002 4Runners 4th gen pickups and 3rd gen 4Runners

New exhaust installed but,

Thread Tools
 
Search this Thread
 
Old Sep 12, 2004 | 05:00 AM
  #1  
george16's Avatar
Thread Starter
Registered User
20 Year Member
 
Joined: Sep 2002
Posts: 513
Likes: 1
From: Florida
New exhaust installed but,

I felt that I lost a lot of low end torque. It's a custom 2 1/4" piping with a stainless Magnaflow muffler installed. Sound is good but like I said I definitely lost a lot of low end torque. Time for the SC i think . Anybody noticed this too? I'll post a pic later.

George
Reply
Old Sep 12, 2004 | 06:09 AM
  #2  
4RUNR's Avatar
Guest
 
Joined: Jun 2003
Posts: 1,615
Likes: 0
From: North Pole
Toyota tunes engines. Meineke welds.
Reply
Old Sep 12, 2004 | 10:38 AM
  #3  
Birdman's Avatar
Registered User
 
Joined: Feb 2004
Posts: 487
Likes: 1
From: Auburn, CA
You may just need to give the ECU time to adjust, although I'm not sure how it would compensate for this. I took out the fuse for the ECU to speed things up just in case. Does anybody know if this type of mod will result in the ECU making any changes to the mix?
Reply
Old Sep 12, 2004 | 10:40 AM
  #4  
Good Times's Avatar
Contributing Member
 
Joined: Dec 2002
Posts: 4,690
Likes: 1
From: Los Angeles, CA
Birdman is definitely on the right track. Whenever you do any performance mods it's a good idea to clear the ECU so that it can relearn w/ the new settings. Give that a try and see if it works. Best to pull the fuse and let it sit for a few minutes.

Good Luck
Reply
Old Sep 12, 2004 | 06:25 PM
  #5  
george16's Avatar
Thread Starter
Registered User
20 Year Member
 
Joined: Sep 2002
Posts: 513
Likes: 1
From: Florida
Thanks guys. I did that this afternoon. I haven't driven it yet since pulling out the EFI fuse so hopefully it'll work out ok. I let you all know the outcome.

George
Reply
Old Sep 12, 2004 | 07:06 PM
  #6  
grams72's Avatar
Registered User
 
Joined: Apr 2004
Posts: 443
Likes: 0
From: Moorhead MN
ECU not EFI
Reply
Old Sep 12, 2004 | 07:15 PM
  #7  
grams72's Avatar
Registered User
 
Joined: Apr 2004
Posts: 443
Likes: 0
From: Moorhead MN
Do you still have the Cat. installed?
Reply
Old Sep 12, 2004 | 07:33 PM
  #8  
AgRunner06's Avatar
Contributing Member
 
Joined: Dec 2002
Posts: 2,424
Likes: 0
From: The Lone Star State
I'm almost 100% positive that the 3.4 is supposed to have 2.5" piping not 2 1/4". I've got 2 1/4" pipe for my exhaust. If that is really what you used then I would say that is why you lost power. You increased the backpressure thus losing power.
Reply
Old Sep 12, 2004 | 07:39 PM
  #9  
george16's Avatar
Thread Starter
Registered User
20 Year Member
 
Joined: Sep 2002
Posts: 513
Likes: 1
From: Florida
Originally Posted by AgRunner06
I'm almost 100% positive that the 3.4 is supposed to have 2.5" piping not 2 1/4". I've got 2 1/4" pipe for my exhaust. If that is really what you used then I would say that is why you lost power. You increased the backpressure thus losing power.
The pipe size for the 3.4 is 2.25". It's not 2.5" as a lot of people think. I did the measurements and have the shop verify it to be 2.25". I actually lost backpressure hence the lost low-end torque.

George
Reply
Old Sep 12, 2004 | 07:40 PM
  #10  
george16's Avatar
Thread Starter
Registered User
20 Year Member
 
Joined: Sep 2002
Posts: 513
Likes: 1
From: Florida
Originally Posted by grams72
Do you still have the Cat. installed?
Yes I do. The stock cat is still installed.

George
Reply
Old Sep 12, 2004 | 07:41 PM
  #11  
george16's Avatar
Thread Starter
Registered User
20 Year Member
 
Joined: Sep 2002
Posts: 513
Likes: 1
From: Florida
Originally Posted by 4RUNR
Toyota tunes engines. Meineke welds.
Good thing I didn't have Meineke do the exhaust .

George
Reply
Old Sep 12, 2004 | 08:51 PM
  #12  
AgRunner06's Avatar
Contributing Member
 
Joined: Dec 2002
Posts: 2,424
Likes: 0
From: The Lone Star State
Originally Posted by george16
The pipe size for the 3.4 is 2.25". It's not 2.5" as a lot of people think. I did the measurements and have the shop verify it to be 2.25". I actually lost backpressure hence the lost low-end torque.

George


Reply
Old Sep 12, 2004 | 08:57 PM
  #13  
george16's Avatar
Thread Starter
Registered User
20 Year Member
 
Joined: Sep 2002
Posts: 513
Likes: 1
From: Florida
Originally Posted by AgRunner06


That info sheet lists the recommended pipe sizes for different type of engines. Unless you have a 3rd generation runner, you will know exactly what the OEM exhaust pipe size is. Go to the dealer with your tape measure and measure it for yourself . I decided have to stay with the OEM size hence I had a 2.25" catback made . The 3.4 only makes about 183 HP at the crank.

George

Last edited by george16; Sep 12, 2004 at 08:59 PM.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Team420
Early Land Cruisers
1
Dec 30, 2015 01:31 PM
RatOmeter
86-95 Trucks & 4Runners
15
Oct 22, 2015 03:17 PM
tj884Rdlx
Newbie Tech Section
25
Aug 28, 2015 12:04 PM
hexrain
Prerunner & All 2WD Rigs
4
Jul 12, 2015 01:13 PM
Coreyr384
86-95 Trucks & 4Runners
2
Jul 10, 2015 11:13 AM




All times are GMT -8. The time now is 08:18 PM.