Home / Toyota Supra Forums

Go Back   Toyota Supra Forums! Join the Supra forum! > Performance, Modification, and Maintenance Forums - for generation specific discussions > MKIII Supra

Reply
 
Thread Tools Display Modes
Old 03-28-2010, 03:45 AM   #1
Arlo444
Stock
 
Join Date: Mar 2010
Location: Euless, TX
Posts: 1
Arlo444 is on a distinguished road
Default Exhaust Recommendation for 90' 7M-GTE

First let me say these forums have been a great source of valuable information. I am in need of exhaust recommendations for my daughter's 90' 7M-GTE turbo. A "friend" replaced the stock down pipe with an aftermarket 3" pipe and removed the front cat. From there it's stock to the rear cat then cat back is 3" HKS. The problem is it fails NOx inspection here in Texas. I've confirmed no vacuum leaks, checked EGR, VSV and recently performed tune up. Need to get it road legal but still want the performance. Suggestions?
Arlo444 is offline   Reply With Quote
Old 03-28-2010, 05:12 AM   #2
Green7mgte
Supra Forum Moderator
 
Join Date: Nov 2009
Location: Green-Ohio
Posts: 1,297
Green7mgte is on a distinguished road
Default

hi, welcome to the bord.

NOx is caused by high combustion temperatures. The EGR reduces the combustion temperature by mixing inert gasses into the air/fuel mix.
retarding the timing will decrease the NOx. You may want to even retard it more than spec by a couple degrees or more. Then after inspection, put it right on spec.

Also fill up with premium. High octane burns slower and should help too. (Less chance of detonation)

Maybe try one step colder spark plugs too. This reduces the chances of a hot center electrode causing pre-ignition.

A lean fuel mixture also burns hotter and may increase NOx. If one injector is spraying lean, that could cause it to burn hotter in that cylinder.

If all else fails, weld in a second universal catalytic converter (in series, not parallel).

(taken from http://answers.yahoo.com/question/in...4113417AA6uoEz

best of luck
__________________

92 Ma71 7mGTE Auto. SafcII
Supra FAQ
Supra MKIII FAQ
Classified Section guidelines :

Green7mgte is offline   Reply With Quote
Reply

Thread Tools
Display Modes

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 Off
Refbacks are Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Exhaust for 7MGE XtreeX MKIII Supra 19 03-25-2010 01:39 AM
Does the exhaust manifold need to come off to replace head gasket? BillW MKIII Supra 1 10-02-2009 12:19 AM
Exhaust Cat Fitting Bill UK MKIII Supra 4 06-15-2008 11:32 AM
exhaust question (not in exhaust faq) sd88supra MKIII Supra 21 11-28-2006 10:52 PM


All times are GMT. The time now is 04:57 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

1986



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87