Notices
Series I Engine Tuning Forum EMS (Flash Tuning, Interceptor, Piggy Back, Stand Alone)

Factory PCM knock control discussion

Old 12-19-2011, 02:05 PM
  #26  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,018
Likes: 0
Received 4 Likes on 4 Posts
So, it must be there for a reason, should I leave it or have it pull less timing?
FazdaRX_8 is offline  
Old 12-19-2011, 03:15 PM
  #27  
Registered
 
Join Date: Sep 2010
Posts: 531
Likes: 0
Received 0 Likes on 0 Posts
For the positive RPM delta values, I think it is there to reduce detonation during transition from cruise to acceleration.

At light loads - as are used in normal everyday cruise conditions - an ignition advance of 40 degrees or more will improve responsiveness and economy. This advance can be used successfully on many engines - even those with an 11:1 compression ratio, if they are being run on high octane fuel. One factor limiting the cruise ignition advance that can be used is the maximum ignition timing attack rate provided by the ECU - that is, how fast the timing can change. If very advanced timing is being used with light loads and the attack rate is not high, there may be slight detonation when the engine load suddenly increases. link
OTOH, I think the Yamamoto books says that this type of detonation isn't problematic for rotaries.

For negative RPM deltas, more advance increases engine braking.

I have run with these tables zeroed, and I didn't have major problems. Still, caveat emptor.

Last edited by oltmann; 12-19-2011 at 03:20 PM. Reason: also
oltmann is offline  
Old 12-20-2011, 01:21 AM
  #28  
Koi no Ousama
iTrader: (25)
 
TeamRX8's Avatar
 
Join Date: Apr 2005
Posts: 20,878
Received 325 Likes on 264 Posts
maybe you should explain why in your mind that it even needs to be messed with?
TeamRX8 is offline  
Old 12-20-2011, 01:39 AM
  #29  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,018
Likes: 0
Received 4 Likes on 4 Posts
Originally Posted by TeamRX8 View Post
maybe you should explain why in your mind that it even needs to be messed with?
to whom are you referring to?
FazdaRX_8 is offline  
Old 12-20-2011, 08:29 AM
  #30  
Koi no Ousama
iTrader: (25)
 
TeamRX8's Avatar
 
Join Date: Apr 2005
Posts: 20,878
Received 325 Likes on 264 Posts
You, why would I be asking anyone else?
TeamRX8 is offline  
Old 12-20-2011, 12:26 PM
  #31  
Registered
 
Join Date: Sep 2010
Posts: 531
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by TeamRX8 View Post
You, why would I be asking anyone else?
Because your question makes no sense -- Fazda never asserted that it does need to be messed with. He merely asked a question.

So, it must be there for a reason, should I leave it or have it pull less timing?
It seems that in turbo applications it might actually be useful to retard the timing somewhat during deceleration, which seems to be the opposite of how things are set up in the OE calibration.

This feature is useful for engine braking under ecology limitations.

In order to avoid rich spices under throttle off it is useful to provide some additional air that is counterproductive for engine braking. Retarded ignition fills the bill.

Secondary, ignition retarded provides inti-lag feature for turbo application if you wish to accelerate sharply after breaking or gear switching. link
oltmann is offline  
Old 12-20-2011, 12:27 PM
  #32  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,018
Likes: 0
Received 4 Likes on 4 Posts
Well it all started looking at 3gear wot logs, right around 5950rpm the car decides its not going any higher, standing on the throttle. Afrs look good, but timming is 5. So I am thinking that having this timming to small that it stalls the cycle, and it cant recover. To early a spark and you loss all power. All my other logs I have seen like to have 9 - 10 on the leading, through that boosted range with out timing pulled. So thats what I am shooting for. I have already adjusted my timing for boost, do I really need another? Maybe this is a rear occurance.
FazdaRX_8 is offline  
Old 12-20-2011, 02:01 PM
  #33  
Registered
 
Join Date: Sep 2010
Posts: 531
Likes: 0
Received 0 Likes on 0 Posts
This is what those tables ought to look like:


So, if you are seeing timing that is 3-8 degrees retarded on the leading and 8 degrees retarded trailing, I think there is a good chance these tables are the cause.

Whether or not it should be "fixed" is really a judgement call.
Attached Thumbnails Factory PCM knock control discussion-delta.png  
oltmann is offline  
Old 12-20-2011, 04:04 PM
  #34  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,018
Likes: 0
Received 4 Likes on 4 Posts
Ah thanks, On the previous page I posted my rpm and timing portion of the log. have you had positive result in adjusting this table for boost?
FazdaRX_8 is offline  
Old 12-20-2011, 04:41 PM
  #35  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,018
Likes: 0
Received 4 Likes on 4 Posts
Originally Posted by TeamRX8 View Post
Ok, I will sit back and watch you run him in useless circles then
Please, if you have something to add, please do, if you dont want to share it openly I have an empty pm box
FazdaRX_8 is offline  
Old 12-20-2011, 10:13 PM
  #36  
Koi no Ousama
iTrader: (25)
 
TeamRX8's Avatar
 
Join Date: Apr 2005
Posts: 20,878
Received 325 Likes on 264 Posts
You don't adjust anything for boost in the RX8 AP. You adjust for load. The difference is subtle, but you need to understand it.

If the engine is stalling at 6k then the problem is elsewhere. The timing would have to be mega-fubar to be the cause of this.
TeamRX8 is offline  
Old 12-21-2011, 02:25 PM
  #37  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,018
Likes: 0
Received 4 Likes on 4 Posts
Ok, ill keep looking.
as a side note wont the power suffer with that kind of timming pull to 5 degrees?
FazdaRX_8 is offline  
Old 12-21-2011, 10:01 PM
  #38  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,018
Likes: 0
Received 4 Likes on 4 Posts
Originally Posted by TeamRX8 View Post
in reference to what? You haven't provided much info. We would need to know the parameters that were occurring then, such as a log, etc.
log.....
Attached Files
File Type: txt
Fazda4_0_6_gg.txt (13.1 KB, 172 views)
FazdaRX_8 is offline  
Old 12-22-2011, 07:32 AM
  #39  
Modulated Moderator
iTrader: (3)
 
dannobre's Avatar
 
Join Date: Feb 2004
Location: Smallville
Posts: 12,809
Received 97 Likes on 94 Posts
Is that log when it's doing it? Would expect higher TP if you were "standing on it" ?
dannobre is offline  
Old 12-22-2011, 07:33 AM
  #40  
Koi no Ousama
iTrader: (25)
 
TeamRX8's Avatar
 
Join Date: Apr 2005
Posts: 20,878
Received 325 Likes on 264 Posts
I'm starting to think the problem is obvious, lol
TeamRX8 is offline  
Old 12-22-2011, 07:37 AM
  #41  
Modulated Moderator
iTrader: (3)
 
dannobre's Avatar
 
Join Date: Feb 2004
Location: Smallville
Posts: 12,809
Received 97 Likes on 94 Posts
The brain attached to the foot that runs the computer taking the logs?
dannobre is offline  
Old 12-22-2011, 08:16 AM
  #42  
Koi no Ousama
iTrader: (25)
 
TeamRX8's Avatar
 
Join Date: Apr 2005
Posts: 20,878
Received 325 Likes on 264 Posts
I was only kidding, but nobody can be of any help without the proper information
TeamRX8 is offline  
Old 12-22-2011, 12:55 PM
  #43  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,018
Likes: 0
Received 4 Likes on 4 Posts
Open excel, click file, open. select all files open text file. Text import wizard opens. Click next. Under delimiters checkbox comma, click next, then finish.

Rx8club does not let .csv or .exel files to be attached
FazdaRX_8 is offline  
Old 12-28-2011, 01:51 AM
  #44  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,018
Likes: 0
Received 4 Likes on 4 Posts
bump
FazdaRX_8 is offline  
Old 12-28-2011, 08:51 PM
  #45  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,018
Likes: 0
Received 4 Likes on 4 Posts
thinking out type

I am hoping its obvious,
the problem is me
you don't have enough info to help me

dannobre looked at my logs and noticed

Throttle Position = 67 (did a search this is the normal max)
Accel. Pedal Pos. =100

Last edited by FazdaRX_8; 12-29-2011 at 12:26 PM.
FazdaRX_8 is offline  
Old 12-30-2011, 02:58 PM
  #46  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,018
Likes: 0
Received 4 Likes on 4 Posts
I am beginning to think I got it backwards, perhaps the hesitation is causing the timing pull.....
FazdaRX_8 is offline  
Old 12-31-2011, 03:54 PM
  #47  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,018
Likes: 0
Received 4 Likes on 4 Posts
2nd gear


3rd gear

Last edited by FazdaRX_8; 01-01-2012 at 01:02 PM.
FazdaRX_8 is offline  
Old 12-31-2011, 08:53 PM
  #48  
Koi no Ousama
iTrader: (25)
 
TeamRX8's Avatar
 
Join Date: Apr 2005
Posts: 20,878
Received 325 Likes on 264 Posts
much better, thank you

now can you provide us with a detailed description on what is occurring and when relative to the log?
TeamRX8 is offline  
Old 01-01-2012, 12:50 AM
  #49  
Registered
iTrader: (1)
 
FazdaRX_8's Avatar
 
Join Date: Jun 2009
Posts: 2,018
Likes: 0
Received 4 Likes on 4 Posts
This is a third gear pull, car accelerates fine, then around 5800 the cars tone changes and it stops accelerating, no jerks, no jolts. Just stops accellerating
FazdaRX_8 is offline  
Old 01-01-2012, 01:46 AM
  #50  
Koi no Ousama
iTrader: (25)
 
TeamRX8's Avatar
 
Join Date: Apr 2005
Posts: 20,878
Received 325 Likes on 264 Posts
Please send me your email address
TeamRX8 is offline  

Thread Tools
Search this Thread
Rate This Thread
Rate This Thread:
You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: Factory PCM knock control discussion


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.