Tune to A/F ratio, track MPH, spark plug reading? - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 08-30-2006, 01:29 PM
hotrodf1's Avatar
Chasing dreams with a ball bat
 
Last photo:
Join Date: Dec 2003
Location: Evansville, IN
Age: 37
Posts: 545
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Tune to A/F ratio, track MPH, spark plug reading?

All,

Just curious what the recommended tuning method is by some of you pros out there.

I'm thinking the latter two, but I dont' have a track handy, and no little device to read deep enough into the plugs. seems like i have seen a little doctors ear inspection device that would better read deep into the plug base.

FBO systems webpage seems to have a good article on reading plugs in the tech section.

ANyone else have any good leads on plug reading articles??

thanks. jer

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 08-30-2006, 02:21 PM
johnsongrass1's Avatar
Race it, Don't rice it!
 
Last photo:
Join Date: Jul 2002
Location: Columbia, Mo
Age: 38
Posts: 4,215
Wiki Edits: 0

Thanks: 0
Thanked 25 Times in 24 Posts
Dyno is alot more accurate.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 08-30-2006, 03:41 PM
Member
 
Join Date: Dec 2004
Location: Madison, WI
Posts: 1,885
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
http://cochise.uia.net/pkelley2/sparkplugreading.html

About the best I have found.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 08-30-2006, 05:02 PM
Registered User
 
Join Date: Aug 2006
Location: California
Posts: 16
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
the more info you have the better i would use all three as for the method of reading the air/fuel mixture the following link is interesting http://www.factorypro.com/dyno/4gasEGAvso2sensor.html

i use a exhaust gas analyzer (otc/spx performance gas) to find what air/fuel mixture the engine wants/needs and use a innovate motorsports lm-1 to check the air/fuel mixture in real world driving conditions

henry @ oles carb
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 08-31-2006, 08:24 AM
hotrodf1's Avatar
Chasing dreams with a ball bat
 
Last photo:
Join Date: Dec 2003
Location: Evansville, IN
Age: 37
Posts: 545
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by Rick WI

Rick and all, Thanks for the info!

I have read the above before and found it very useful. It's in my binder in fact.

Now read this from FBO systems (Fat, bald, old he he.) http://www.4secondsflat.com/Spark_plug_reading.html

There are some serious differances there. For example, the first article talks about using the ground strap to determine heat range. The second talks about the strap giving you an indication of the timing in the motor (relative) - but he states that you must have the correct heat range plug already. I guess both have to do with combustion temps?

First article basically says the porcelain is useless for reading - the second says it gives you A/F ratio at different engine loads and speeds.

Hmmmmm.

what shakes out at the end of the day??
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 08-31-2006, 08:36 AM
hotrodf1's Avatar
Chasing dreams with a ball bat
 
Last photo:
Join Date: Dec 2003
Location: Evansville, IN
Age: 37
Posts: 545
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by olescarb
the more info you have the better i would use all three as for the method of reading the air/fuel mixture the following link is interesting http://www.factorypro.com/dyno/4gasEGAvso2sensor.html

i use a exhaust gas analyzer (otc/spx performance gas) to find what air/fuel mixture the engine wants/needs and use a innovate motorsports lm-1 to check the air/fuel mixture in real world driving conditions

henry @ oles carb

Very cool stuff! That sounds like it would be the stuff. I have encountered some of the things he talks about with the O2. makes me wonder really how useful they are. sounds like the plugs will tell you more if you truly know how to read them.

How much for one of those 4 gas analyzers? Or is this the "If you have to ask . . . ." deal.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 08-31-2006, 09:22 AM
johnsongrass1's Avatar
Race it, Don't rice it!
 
Last photo:
Join Date: Jul 2002
Location: Columbia, Mo
Age: 38
Posts: 4,215
Wiki Edits: 0

Thanks: 0
Thanked 25 Times in 24 Posts
I agree to almost nothing on the second article.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 08-31-2006, 10:45 AM
hotrodf1's Avatar
Chasing dreams with a ball bat
 
Last photo:
Join Date: Dec 2003
Location: Evansville, IN
Age: 37
Posts: 545
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
so is there any science to reading plugs or just one dude's opinion to another???

there must be something.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 08-31-2006, 11:37 AM
Member
 
Join Date: Dec 2004
Location: Madison, WI
Posts: 1,885
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
I think the FactoryPro example is very biased from a sales standpoint and is aimed at countering the DynoJet air/fuel programmer they sell with their motorcycle dynos. FactoryPro is a motorcycle parts manufacturer. Exhaust gas is certainly a way to dial in fuel air mix no question. The bottom line, as with all methods, is what does the engine want. The dyno and the track is the only way to confirm that in the end.

In the FactoryPro example I don't have any idea on their concepts of timing versus gas analysis, never played with that. No doubt it has an affect though, all you have to do is look at EGT changes relative to timing changes at idle.

On the FBO example it's best to keep it simple for us average folk. The base of the plug will give you a pic of what the combustion chamber is doing and therefore gives you the burn and therefore fueling.

After dialing in a motor on the dyno with 60 data points monitored, tracked and recorded plugs from these engines look EXACTLY like those I posted in the link. It would be interesting to bring the 5 gas analyzer we have into the dyno cell and see what it shows. I don't think I'll get into that to soon though.

The other thing worth noting, and something I'm going to be upgrading to on the dyno is that the top end race dynos not only use wideband AFR for tuning but they now use 8 wideband O2's, one in each cylinder. Not only is the trend towards O2's pretty strong out there for tuning it's getting VERY precise. The goal is to balance each cylinder, which as we found out in Chicago at the NMCA race, some will run leaner than others when your on the edge and crush pistons.
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 08-31-2006, 12:05 PM
hotrodf1's Avatar
Chasing dreams with a ball bat
 
Last photo:
Join Date: Dec 2003
Location: Evansville, IN
Age: 37
Posts: 545
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
So should a guy pony up the cash for a wideband or is it really not worth it? it seems like WOT tuning could be done at the track referencing the plugs. But at cruise that doesn't leave you much to go on.

I guess i would like to get it tuned the best everywhere in the load / speed range. I would like to think that jets, air bleeds, IFRs and PVCRs would get me there - but probably not without the wideband and lots of time and trial and error. In the end would it be worth a few MPGs? If only a few, then why bother?

Looking back on it now, it wouldn't have been that much more to do a 950 commander system TBI - which would have satisfied every angle I can think of, once i upgraded to wideband on it.
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 08-31-2006, 12:24 PM
Member
 
Join Date: Dec 2004
Location: Madison, WI
Posts: 1,885
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Yes, a wideband system with datalogging is a very worthwhile tuning tool. You are correct, the 950 would have been nice and your hands wouldn't smell like gas while your tuning.
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 08-31-2006, 01:09 PM
Registered User
 
Join Date: Aug 2006
Location: California
Posts: 16
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
the readings from a wide band air/fuel meter can be less than accurate if you have a missfire, the blow thru effect from a supercharger or a "hot" cam at low engine speeds due to the extra oxygen the sensor will see in the exhaust.
the factory-pro article has some good concepts on tuning. a 5 gas exhaust gas analyzer can tell you the a/f mixture as CO (carbon monxide) and read missfire as HC (hydrocarbons) then you can tune the ignition timing the engine needs/wants by tuning for the highest co2 and the lowest HC (hydrocarbons/missfire). you can also read the oxygen in the exhaust and a high NOx reading is a good indicator of detonation.

i need all the data i can get to tune so i read the plugs, tune to make power plus use both a wideband and a 5-gas exhaust gas analyzer. I am working on a ford racing 392 engine with webers and i would be lost if i did not use both the 5-gas and the wideband o2 sensor.

if anyone is interested in more info on tuning with a 5-gas analyzer take a look at http://www.automotiveu.com/

henry @ oles carb
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 08-31-2006, 03:50 PM
johnsongrass1's Avatar
Race it, Don't rice it!
 
Last photo:
Join Date: Jul 2002
Location: Columbia, Mo
Age: 38
Posts: 4,215
Wiki Edits: 0

Thanks: 0
Thanked 25 Times in 24 Posts
How much good will those settings do a person when the atmosphere changes so rapidly?. I used to spend a dozen hours a week tuning our race engine with timing and fuel distribution only to realize that I'm chasing my tail all night becuase the weather changed right in the middle of a race sometimes. Now I took all that info and condensed it to a temp range. Hot and muggy, cool and damp, hot and dry, or stormy. The time I save I spend with driver skills.

I think it's great that technolgy has allowed us to optimize for near perfect conditions. But without fule injection to update the fuel and timing maps multiple times per second, a cab can't do this, what works at the top of the hill isn't perfect at the bottom.

How can plugs be "read" at part throttle with out being run at a constant part throttle. The street doesn't allow this because of traffic and elevation changes.
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 08-31-2006, 03:55 PM
Registered User
 
Join Date: Aug 2006
Location: California
Posts: 16
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
i forgot to mention that one other tuning tool you need is a weather station such as a RaceAir Pro from Computech, this tool can help you figure out what the density altitude is when you get your perfect tune and then make suggestions as what jet changes to make. that info plus a lot of experiance can keep you ahead of the other racer

henry @ oles carb
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 08-31-2006, 03:56 PM
Member
 
Join Date: Dec 2004
Location: Madison, WI
Posts: 1,885
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Agreed Henry, that misfires will drive an O2 sensor up the wall. We have always looked at the 5 gas analyzer as a diagnostic tool, ours is the newer Snap On model that includes full ignition diagnostics and waveform output as well. Never have dragged it into the dyno cell but it certainly would be interesting to do someday.

For the average Joe though wanting to improve his tuneup for a couple/few hundred bucks a O2 wideband kit is a very easy way to accomplish things. I don't know what a portable datalogging 4 or 5 gas analyzer would run but might be interesting to find out someday.

From a hardcore race standpoint the debacle of the last NMCA race in Chicago tells me that individual tuning of each cylinder is the way to go when your pushing the enge of tune with 500 HP of port injected nitrous and making 1400 to 1500 horse to the wheels. That's why I'm pretty set on upgrading in the near future. Tuning by cylinder seems to be what the world is coming to, wondering if your seeing the same thing.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may 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 On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
what is the fastest (factory) car you have ever driven? badknuckles Hotrodders' Lounge 320 12-09-2011 02:32 AM
Ignition system info................ poncho62 Electrical 18 10-11-2008 11:10 PM
A/F ratio vs %CO question Jmark Engine 6 09-12-2005 01:04 PM
4L80E diesel computer 5foot2 Transmission - Rearend 2 04-09-2005 01:48 PM
Help...Spark plug reading Slant3 Engine 12 09-18-2004 08:00 AM


All times are GMT -6. The time now is 07:41 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.