Welcome to the North American Subaru Impreza Owners Club Monday December 22, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Engine Management & Tuning

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 02-02-2004, 12:31 AM   #1
03BlackRex03
Scooby Newbie
 
Member#: 53488
Join Date: Jan 2004
Location: Atlanta, GA
Default Engine Knock w UTEC

I know this sounds kinda newbish, but I have always had a bad problem with engine knock. From stage 1, to stage 2, and now to my current setup.

When I got my stage 2 (4k miles on the car) and loaded the default stage 2 map I had extreme bad knock running with the set figures and boost.... I had to retard the timing 3 degrees, up fuel by .5 and lower boost by 1 1/2 lbs to get away from it.
I didn't think much of it due to cyl #3 running lean and thought it would be fixed in time by upgrades. Now that I'm running a FMIC, VF22, STi injectors, 255lph Pump, and a Perrin Fuel rail i thought for sure I would have less issues with detonation running conservative maps, but yet again, 4 points of timing and over 1 fuel point off the TurboXS Stage4+FMIC map (I know its not for a vf22) just to run the 17.5 PSI in 4th gear like they recommend. After I was done tuning this map (no knock) the best I could without gauges (always on the rich side; 2 timing and .3 from my last seen knock on 93 octane) I was happy with the car until I met up with a friend of mine running an STi (Stock). 20-100, 0-60, 50-120, all race matches we ran (private track) we were within 1 or 2 car lengths top.
After reading the TXS Stage 4 (368hp I believe, on a smaller turbo and stock intercooler) I thought this couldn't be right. I should be somewhere between 340-380 since I'm sure the car is not greatly tuned (without gauges) and should gain a lot more on an STi; so I started to play around with tuning again; to no prevail. I always end up with slight knock (1-3 count) no matter what I run. More timing, less boost. More boost, retarded timing.
Can anybody shed any insight into this problem and anything I might be overlooking. You can look at the TXS stage4+fmic on there website and see that is more than conservative on timing as is.

Sorry for the long post and thanks for your insight.

Current Mods:
TXS Uppipe
TXS TBE (Catless)
TXS Shortie Intake
Perrin FMIC
VF22
STi Injectors
255lph Pump
Perrin Fuel Rail

Thanks, Jason
* Registered users of the site do not see these ads.
03BlackRex03 is offline   Reply With Quote
Old 02-02-2004, 08:46 AM   #2
03BlackRex03
Scooby Newbie
 
Member#: 53488
Join Date: Jan 2004
Location: Atlanta, GA
Default

^
03BlackRex03 is offline   Reply With Quote
Old 02-02-2004, 09:52 AM   #3
PaulRex
Scooby Guru
 
Member#: 12454
Join Date: Nov 2001
Chapter/Region: Tri-State
Location: Vermont
Vehicle:
10 Toyota Taco
K8 SV650SF

Default

My insight is that you if your going to be doing your own tuning you should get your hands on an in car WB, and an EGT gauge. FWIW i've beaten a few stg.4 wrx's in my car when i had stock turbo/intercooler and a few STIs too. Some of those stg.4s just running base maps dont make alot of power, go get tuned and unless there is some other problem like bad sparkplugs or etc. then you should gain alot of power.

Paul
PaulRex is offline   Reply With Quote
Old 02-02-2004, 12:31 PM   #4
mick_the_ginge
Citizen Mick
 
Member#: 27646
Join Date: Oct 2002
Chapter/Region: NWIC
Location: Portland, Oregon
Vehicle:
2003 Sleeved 2.5
Oil Dry Sump Goodness

Default

Ditto, you need a WB to tune your fuel. Too much fuel can cause prime knock conditions. When I was running rich I also had the same issue. You have to remove so much timing before knock goes away.
mick_the_ginge is offline   Reply With Quote
Old 02-02-2004, 07:42 PM   #5
03BlackRex03
Scooby Newbie
 
Member#: 53488
Join Date: Jan 2004
Location: Atlanta, GA
Default

Any recommendation than the TXS tuner (700 bucks =/ ) Also can an egt gauge be installed on the stock EGT probe location with the stock probe? I know its the not the best readings that far away from the manifold, but say if I reduced the threshold to 675/1425 degrees would that be "ok" to tune on if I had a WB?

I've read you can put a WB O2 in the rear sensor where stock used to be running catless, anybody know which sensor and gauge I should use for that threads that is less than the TXS Tuner.

Thanks, Jason
03BlackRex03 is offline   Reply With Quote
Old 02-05-2004, 05:48 PM   #6
bebeGDB
Scooby Newbie
 
Member#: 52818
Join Date: Jan 2004
Location: toronto
Vehicle:
2003 wrx
bule

Default

well sti injector is max out by the stock turbo already plus you have a vf 22 i will suggest you go higher injector specially #3 cilnder try 750 cc at least. plus did you do anything to your engine?? if you did move the engine around then you timing need to be reset??!!!
bebeGDB is offline   Reply With Quote
Old 02-05-2004, 05:54 PM   #7
02WRX_BLUE
Scooby Specialist
 
Member#: 13704
Join Date: Dec 2001
Location: Chester Springs, PA
Vehicle:
2006 EVO MR
Apex Silver

Default

Post your log and Map here. So that we can all get an idea of where you are getting knock and how your map is set...
02WRX_BLUE is offline   Reply With Quote
Old 02-05-2004, 06:00 PM   #8
mick_the_ginge
Citizen Mick
 
Member#: 27646
Join Date: Oct 2002
Chapter/Region: NWIC
Location: Portland, Oregon
Vehicle:
2003 Sleeved 2.5
Oil Dry Sump Goodness

Default

Without seeing a real log I am only going to guess but I doubt you need more fuel, you need less.

The TurboXS is rich at the top end. Too much fuel will lead to prime knock conditions.

When the UTEC is control it is controlling the timing so typically a ecu reset will make no difference. If it does then your long term and short term fuel trims are screwed up. Typically these are ok with the setting found in the FMIC map.

If your car is a 2004 you will be running into the closed/open loop fueling issue. What year is your car?

Off subject but how do you like the Perrin FMIC? Huge and good looking.
mick_the_ginge 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
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
G35 engine Knock vs WRX STi engine Knock... BBBsti LTD General Community 6 03-21-2007 02:40 AM
Weird Knock noise, dont think its engine knock mlotek Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) 1 07-14-2006 10:12 PM
Engine knock and rough running engine Chi_San Legacy Forum 1 07-23-2004 12:57 PM
UTEC engine knocking when cold WRXOwner7 Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) 11 12-29-2002 09:10 PM


All times are GMT -4. The time now is 08:21 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.