Go Back   EcoModder Forum > EcoModding > DIY / How-to
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 12-14-2011, 04:52 AM   #11 (permalink)
Eco-ventor
 
jakobnev's Avatar
 
Join Date: Oct 2010
Location: sweden
Posts: 1,209

Princess - '92 Mazda MX-3 GS
House of Tudor
Team Mazda
90 day: 53.54 mpg (US)
Thanks: 48
Thanked 409 Times in 259 Posts
Send a message via MSN to jakobnev
Quote:
if I reset the timing without jumping the ECU, the computer switched it back. If I recall properly, I just about watched the pulley move back to stock timing.
It might have been resetting idle speed by adjusting timing, not resetting base timing. Idle should have initially increased a bit when you turned the distributor.

__________________




2016: 128.75L for 1875.00km => 6.87L/100km (34.3MPG US)
2017: 209.14L for 4244.00km => 4.93L/100km (47.7MPG US)
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 12-14-2011, 07:43 PM   #12 (permalink)
Master EcoModder
 
Join Date: Jul 2008
Location: Silly-Con Valley
Posts: 1,417
Thanks: 173
Thanked 226 Times in 174 Posts
Most cars in the last couple of decades have automatic idle stabilization with more than enough control authority to keep the idle RPM steady with a small advance in ignition timing like that.

Generally cars are built with safety margins in just about everything important. Spark advance is such a thing--if a car does not have a knock sensor, the timing is almost always set such that even going uphill in Death Valley on a 110 degree day the car will not knock. Advancing the timing can cut into that margin, but under most driving conditions it won't matter.

If a car does have a knock sensor, chances are that it is set up to run much closer to the "ragged edge" where knock occurs. In that case adding static timing will mostly cause the knock sensor to retard the timing more than if it were in the stock position. Which basically gives you no effect from the mod.

I doubt that two degrees' advance will hurt anything in this case.

-soD
  Reply With Quote
Old 03-26-2012, 11:23 PM   #13 (permalink)
Master EcoModder
 
cbaber's Avatar
 
Join Date: Feb 2012
Location: Missouri
Posts: 540

Lean and Mean - '98 Honda Civic HX
Team Honda
90 day: 46.69 mpg (US)
Thanks: 30
Thanked 190 Times in 110 Posts
I know this thread is old but its important for potential DIY'ers to know that the #1 cylinder on Honda engines is the one farthest to the right (drivers side), not to the left near the distributor. I don't know if this effects setting your timing or not, but probably not since it seemed to work ok for you.
__________________
1998 Honda Civic HX - My Project Thread

  Reply With Quote
The Following 2 Users Say Thank You to cbaber For This Useful Post:
California98Civic (07-24-2012), MobilOne (05-02-2015)
Old 03-27-2012, 01:29 PM   #14 (permalink)
EcoMod Proof of Concept
 
WD40's Avatar
 
Join Date: Mar 2008
Location: Chilliwack B.C. CANADA
Posts: 243

WD-40's Insight - '00 Honda Insight
Gen-1 Insights
Team Honda
90 day: 56.04 mpg (US)

WD-40's Mirage - '15 Mitsubushi Mirage ES
Mitsubishi
90 day: 46.05 mpg (US)
Thanks: 80
Thanked 84 Times in 44 Posts
An old indian (Nothing racist intended) trick to allow you to see the mark on the timing belt pulley is to use white chalk on it and rub off the excess.
The mark is cut into the pulley so rubbing off the excess leaves only the cut full of chalk. Now its bright and easy to see with the timing light.
__________________
2000 Insight MT 106K Citrus A/C
  Reply With Quote
Old 03-27-2012, 11:24 PM   #15 (permalink)
EcoModding Lurker
 
Join Date: Mar 2012
Location: Houston
Posts: 46

truck - '06 Chevrolet Silverado WT
90 day: 22.65 mpg (US)
Thanks: 0
Thanked 1 Time in 1 Post
california98civic - do you have any small logger or scan gauge device able to measure engine knock? A widely used way to tune for gas mileage is to increase advance until knock then back off slightly, but then because you have no access to multiple tuning tables (VE, spark, throttle, pressure, airflow, rpm etc), you'd have to test for knock at WOT to be safe, then back off if it was knocking some at WOT (I thought all 1.6 civics of your year model had knock sensors). Short of that, a few degrees advance won't hurt anything (set back to stock for emissions time), unless it throws a code. If it throws a code after advancing the dizzy while driving, it's likely enriching the AFR and running in open loop (no fuel trims running off O2 sensors) then the adjustment was for nothing. Have you thought about a Hondata tune or do you already have one?

Quote:
Originally Posted by jakobnev View Post
Actually, the notion of the ECU undoing your changes is a myth, it couldn't possibly, it doesn't even know you have made any! The reason the car must be put in test engine mode is that it fixes the timing to a certain value, in normal mode the timing might be all over the place, making it impossible to adjust meaningfully with a light.
This depends on the vehicle, some vehicles with cam sensors run off spark maps in the ECU and no matter how much the dizzy is turned or what procedure is used, timing won't increase or decrease (it'll just be really out of tune with respect to the degreeing of the cam). Also some vehicles can adjust base/idle timing with the dizzy but won't affect engine under load, depends a lot on the vehicle/ECU/distributor. Honda's are pretty simple.
  Reply With Quote
Old 03-28-2012, 12:00 AM   #16 (permalink)
Master EcoModder
 
mwebb's Avatar
 
Join Date: Jul 2009
Location: New York
Posts: 506

no nickname , it's just a car - '04 volkswagen golf tdi
Thanks: 2
Thanked 101 Times in 74 Posts
bad idea - no gains - misery to be had

Quote:
Originally Posted by California98Civic View Post
Thanks for the caution. I appreciate it.

Here's an interesting link for anyone wanting more detail about advancing the timing and torque and other issues: What Happens When the Timing Is Advanced

Regards,
james
....The risk in advancing the timing is that the flame front (the increase in pressure) from the burning air/fuel mix strikes the piston head before, at, or too close to TDC to create the optimum forward rotation of the crank.

If the downward force reaches the top of the piston before the piston is able to react with a downward motion then the force is directly to the crank, rather than to the rotation (a bit like how landing on a stiff leg transmits the jar to the hip). .....


from the link -
peak combustion pressure must happen at 14 degrees ATDC for best results
always
except at idle
except on start

if you tamper with base ignition timing - you change peak combustion pressure timing by the amount of your tampering


there are already inconsistencies in peak combustion pressure timing events in non tampered with systems - if you move the average of those peaks back by advancing base ign timing some of those peaks will overlap
TDC

peak combustion pressure will happen before the piston has reached TDC
which is
bad

this is a very bad idea -
  Reply With Quote
Old 03-28-2012, 12:18 AM   #17 (permalink)
Master EcoModder
 
mwebb's Avatar
 
Join Date: Jul 2009
Location: New York
Posts: 506

no nickname , it's just a car - '04 volkswagen golf tdi
Thanks: 2
Thanked 101 Times in 74 Posts
knock retard per cylinder graphed



this shows knock retard per cylinder in a VW Passat
Knock retard is the correction in ignition timing to prevent spark knock .
this system has so much ping that there is around 60kw of knock retard at 40% of calculated load
which on this system will peak around 95% - here it is much less

consider that the 4 cylinder vw engine in the jetta from that year has only 85kw maximum power output

why ?
customer is using poor quality 87 octane in an engine designed for 93octane and has been for some time , heavy carbon deposits from partial misfires have increased compression ratio in all cylinders
the car can not get out of it's own way ....

there are no DTCs and the "check money" light is off .

this is what a system that has knock correction will do if you advance base ignition timing beyond specification.
on a system without knock correction , results can be much worse

fix ?
solvents injected to clean carbon from combustion chambers and a tank of the correct top tier premium shell gas -
customer did not believe the difference this would cause ... until he felt it .

Last edited by mwebb; 03-28-2012 at 12:20 AM.. Reason: no DTCs
  Reply With Quote
Old 03-28-2012, 12:33 AM   #18 (permalink)
EcoModding Lurker
 
Join Date: Mar 2012
Location: Houston
Posts: 46

truck - '06 Chevrolet Silverado WT
90 day: 22.65 mpg (US)
Thanks: 0
Thanked 1 Time in 1 Post
mwebb - if caly98 is only advancing 2 deg, nothings going to be hurt, especially if he drives for mileage, he'll never get anywhere near the peak combustion temps that kill engines. Ideally he'd go through some type of tuner that will only increase spark in a closed loop while cruising at a certain rpm range. But that's much more expensive than just turning the distributor
  Reply With Quote
Old 03-28-2012, 01:24 PM   #19 (permalink)
Cyborg ECU
 
California98Civic's Avatar
 
Join Date: Mar 2011
Location: Coastal Southern California
Posts: 5,213

Black and Green - '98 Honda Civic DX Coupe
Team Honda
90 day: 64.33 mpg (US)

Black and Red - '00 Nashbar Custom built eBike
90 day: 3671.43 mpg (US)
Thanks: 1,855
Thanked 1,552 Times in 1,056 Posts
Quote:
Originally Posted by mja1 View Post
california98civic - do you have any small logger or scan gauge device able to measure engine knock? A widely used way to tune for gas mileage is to increase advance until knock then back off slightly, but then because you have no access to multiple tuning tables (VE, spark, throttle, pressure, airflow, rpm etc), you'd have to test for knock at WOT to be safe, then back off if it was knocking some at WOT
I have a scan tool that I bought for diagnostic purposes, and it offers some data my ultra gauge does not. But since I don't have a MAF sensor, I would not have that data on the tool either. By "spark" do you mean a timing advance readout or something else? Because the timing advance data would be inaccurate once I jump the system and start changing timing at the distributor.

Quote:
Originally Posted by mja1 View Post
Have you thought about a Hondata tune or do you already have one?
I have thought about Hondata, and looked into it. My specific OBD2 ECU is not ideal for their services, though other 6th Gen Civic trim levels are (such as the EX). I wish I had a 2005+ HX. Its redesigned ECU is specifically cited as one that Hondata will tune for MPG if desired. That would be cool.

Quote:
Originally Posted by mwebb View Post
peak combustion pressure will happen before the piston has reached TDC
which is
bad

this is a very bad idea -
This would be true with a more aggressive advance, which I did not do, and with more aggressive driving, which I don't do. I advanced 2* and the car never crosses 2500/2600 RPMs. It will sit at lower cruise levels soon, when I switch-out the final drive gear for a VX 3.250:1 gear.

Lastly, I advanced the timing last May and have driven at least 10,000 miles since then. I'm fine.

Thanks for your concern and for offering your cautions to readers.

[EDIT: btw, I just remembered that one of your fixes I already do... I have been running 89 Octane for months.]
__________________


See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.


Last edited by California98Civic; 03-28-2012 at 06:47 PM..
  Reply With Quote
Old 03-28-2012, 04:42 PM   #20 (permalink)
EcoModding Lurker
 
Join Date: Mar 2012
Location: Houston
Posts: 46

truck - '06 Chevrolet Silverado WT
90 day: 22.65 mpg (US)
Thanks: 0
Thanked 1 Time in 1 Post
Quote:
Originally Posted by California98Civic View Post
I have a scan tool that I bought for diagnostic purposes, and it offers some data my ultra gauge does not. But since I don't have a MAF sensor, I would not have that data on the tool either. By "spark" do you mean a timing advance readout or something else? Because the timing advance data would be inaccurate once I jump the system and start changing timing at the distributor.
Yes by 'spark' I mean spark advance, most tuners have these tables it's what you may know as a 'low octane' or 'high octane' tune (all that's changed between those two tunes is the spark advance). Yes, honda's use speed density, tune by MAP sensor, I'm not very familiar with honda ECU's when did they go over to MAF or have they yet? Its actually very easy to tune speed density system if you had some type of software that would allow you to change the ignition spark while keeping your idle spark/idle circuit stock, which is the ideal situation. Sadly I see no spark map parameters on the hondata tech website, which I assume people are adding aftermarket ignition systems for boost retard or N/A advance at certain rpm? Like I say don't know too much about these honda ECU's.

Quote:
I have thought about Hondata, and looked into it. My specific OBD2 ECU is not ideal for their services, though other 6th Gen Civic trim levels are (such as the EX). I wish I had a 2005+ HX. Its redesigned ECU is specifically cited as one that Hondata will tune for MPG if desired. That would be cool.
I'm not positive but I'm pretty sure your ECU is supported:
Applications By Vehicle
Though they may not send out a 'gas mileage' generic tuned ECU, you'd have to do it yourself. By the mid 2000's I'm sure they have spark advance maps available, but you never know with honda, it seems like if something works they don't change much for a few decades.

One feature that would greatly benefit your goal is the hondata fuel tables, you'd have to buy a hondata tuning system and a wideband O2 sensor (PLX about 150$ last I checked) and have access to a good laptop, this would allow you to really lean out your engine, or within a certain rpm range/throttle input etc. You can save different tunes on your computer or wherever, so if something doesn't work just modify or start over from stock tune. Leaning it out from its current 14-14.7 (assuming its in good running condition) to 15-16 AFR will net a few more mpg's, the trick is to lean out the AFR until just before the catalytic converter/narrowband O2 sensors tell the ECU to add more fuel so the cat doesn't burn up and gas mileage decrease from the ECU adding fuel. Harder to explain than it is in practice.

Technical Information
Tech - Wideband tuning

edit:
Civic 96-99 US D16Y P2P P72,P28,P30,P61,P08J,P30J,P72J s100/s200/s300 2,6,7

Civic 96-99 US D16_ P2E P74,P75,P06,PR4,P72,P28,P30,P61,P08J,P30J,P72J s100/s200/s300 2,6,7
2. Manual transmissions only.
6. OBDII to OBDI adapter harness required.
7. OBDI ECU swap.

- if yours is a manual, seems like you can use the hondata with an ECU swap and adapter, call hondata for details if you go that route


Last edited by mja1; 03-28-2012 at 05:18 PM..
  Reply With Quote
The Following User Says Thank You to mja1 For This Useful Post:
California98Civic (03-28-2012)
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com