Stage 2 complete, up timing or up boost?

[Denji]

Okay, i finally completed all my mods including in general stage 2 components.
Mods in profile are current, I've gotten used to logging and tuning with ECUplus and so i'm ready to make this car move.. maybe.

Okay, first i'd like to mention that my car is not a track car, it is a daily driver to commute to school and back and has 157,000 miles on it, stock engine completely, at least to my knowledge.

Compression test results are as follows from left to right on the cylinders if looking in engine bay.

210,210,209,209

Current boost=16-17 psi

gas= 93 octane pump

Is it better to run lower boost and try to advance timing or push the boost and run less advance? What is a good rule of thumb limit where i have a good compromise of power and reliability?

 

[2gGSX]

Your compression seems sort of high. Have you checked your base timing, especially if the intake cam has skipped timing? Carbon deposits perhaps?

Every tuner (incl. you eventually) has a different opinion of how to balance out AFR, timing, and boost. Some people like lower AFR and timing for more boost, some stick vehemently to 11:1 while sacrificing boost and/or timing, etc. In the end, I'm pretty sure you're just limited by your gas.

For instance, no matter what I do, I can't get the car to go faster than a 2.1 second 70-90 mph time. Leaning it out created more knock, and I had to pull timing. 2.1. Running less boost while leaning it out and adding a little timing yielded less airflow, but again, 2.1.

Play around with it, that's half the fun of tuning.

 

[CanadianTSi]

I would have to say 20psi would be a good balance of power and reliability.

 

[Denji]

Yeah, I assume carbon deposits since base timing is good. 93 octane is the premium fuel standard here.

I've read a lot of different opinions about the stock head gasket and boost. Is 20 generally accepted as an okay amount of boost in this regard?

 

[turboglenn]

Run a can of seafoam through the intake ( search, there's threads on it ) and then up the boost to 20 and keep an eye on it as far as timing and AFR. My stock motor popped at 19 -20ish at the track becuase of a lean condition, but i've seen one DSM with almost 160k miles pushing his B16G to 22 PSI on the streets daily.

Try and run 11.5:1 AFR if you can, it is at the very least a safe AFR... that's my favorite target AFR on my DSM.

Finding the right boost pressure and timing curve is a lot of fun and you'll learn quite a bit about tuning doing it. Start out with the timing at 16 or so and the boost to 20. then play with adding some timing untill you get some knock, then back it off 2*. Now start playing with more boost if you like and watch for knock or just leave it there. For a long time i was a firm believer in "more timing less boost" but now days i keep timing rather conservative. 20* BTDC on my car from 6k RPM and up, and it is a few degrees less in the lower ranges from 3 -5k RPM i start at about 16 and work it up with the revs. These motors tend to like a little less timing in the peak torque areas around 4500 RPM from all the logging i've done on cars that still have knock sensors. I think i might buy a J&S for my car this year, i've wanted one since i got the wastegate dumping to the atmosphere and can't hear the motor that well now.

 

[Denji]

Run a can of seafoam through the intake ( search, there's threads on it ) and then up the boost to 20 and keep an eye on it as far as timing and AFR. My stock motor popped at 19 -20ish at the track becuase of a lean condition, but i've seen one DSM with almost 160k miles pushing his B16G to 22 PSI on the streets daily.

Try and run 11.5:1 AFR if you can, it is at the very least a safe AFR... that's my favorite target AFR on my DSM.

Finding the right boost pressure and timing curve is a lot of fun and you'll learn quite a bit about tuning doing it. Start out with the timing at 16 or so and the boost to 20. then play with adding some timing untill you get some knock, then back it off 2*. Now start playing with more boost if you like and watch for knock or just leave it there. For a long time i was a firm believer in "more timing less boost" but now days i keep timing rather conservative. 20* BTDC on my car from 6k RPM and up, and it is a few degrees less in the lower ranges from 3 -5k RPM i start at about 16 and work it up with the revs. These motors tend to like a little less timing in the peak torque areas around 4500 RPM from all the logging i've done on cars that still have knock sensors. I think i might buy a J&S for my car this year, i've wanted one since i got the wastegate dumping to the atmosphere and can't hear the motor that well now.

I'm having a hard time convincing myself to add the seafoam. I've been logging and i can see no ill side effects of the carbon build up. Timing stock is around +19 at top of gear and i'm not having any problem with knock. What would be the benefit of doing this? I figured maybe removing the carbon would cause me to have to do a rebuild due to too low of compression after my carbon sealant was removed.

 

[CanadianTSi]

I ran my stock headgasket/studs 200,000km 7bolt at 24psi on a 50 trim for a full season with no ill effects.

 

[fourreGsixty3]

Well its caked up on top of your pistons, and this is BAD! Actually having carbon build up is bad because it conducts heat VERY easily, and retains it so you get hot spots on pistons, ect...

This conversation is somewhat similar to what your asking... http://www.dsmtuners.com/forums/tuning-engine-management/274914-timing-vs-afr.html

 

[Denji]

Well its caked up on top of your pistons, and this is BAD! Actually having carbon build up is bad because it conducts heat VERY easily, and retains it so you get hot spots on pistons, ect...

This conversation is somewhat similar to what your asking... http://www.dsmtuners.com/forums/tuning-engine-management/274914-timing-vs-afr.html

As far as i know, carbon is a relatively good insulator, which, in turn should cause hotspots possibly. But thats just speculation.

And it appears as if that is the same question, just asked differently. Thanks.

 

[JayRolla]

I would tune to a good 11.1 afr. Start at 20psi and if you have knock anywhere pull a little timing out of that rpm range till you have no knock. Then add 2psi and pull a little timing till you have knock. Do this till you cant add anymore boost and you stay at least above 15* advance. You dont want to go too low on the timing on stock internals because they cant handle the heat that it causes. I be you could run 22-24psi with a little lower timing.

 

[2gGSX]

I would tune to a good 11.1 afr. Start at 20psi and if you have knock anywhere pull a little timing out of that rpm range till you have no knock. Then add 2psi and pull a little timing till you have knock. Do this till you cant add anymore boost and you stay at least above 15* advance. You dont want to go too low on the timing on stock internals because they cant handle the heat that it causes. I be you could run 22-24psi with a little lower timing.

Do you realize that he has a 2g and starts off at having 16* peak timing advance? What you're telling him to do almost doesn't make sense--pull timing to run more boost, but stay above 15* advance. That 1 degree of timing will likely not allow him to run giant amounts of boost on a 16g of all turbos, which is already known to create high intake charge temps.

Furthermore, Matt (dsm-onster) already stated that retarding timing does not increase the heat of combustion in the cylinder, only in the exhaust track. This would make sense, since if it increased the heat of combustion you would actually GAIN power from retarding timing since the combustion charge would expand more under the higher level of heat, which would create a greater force on the pistons/bottom end.

 

[Spln_Hrd]

I am with turboglenn on this, but its all personal preferance.

Guys have made gobs of power both ways. 20 PSI is where I would like to see a 16g turbo because it is loosing efficiency soon after that.

 

[JayRolla]

Do you realize that he has a 2g and starts off at having 16* peak timing advance? What you're telling him to do almost doesn't make sense--pull timing to run more boost, but stay above 15* advance. That 1 degree of timing will likely not allow him to run giant amounts of boost on a 16g of all turbos, which is already known to create high intake charge temps.

Furthermore, Matt (dsm-onster) already stated that retarding timing does not increase the heat of combustion in the cylinder, only in the exhaust track. This would make sense, since if it increased the heat of combustion you would actually GAIN power from retarding timing since the combustion charge would expand more under the higher level of heat, which would create a greater force on the pistons/bottom end.

that is true. I thought 2g's hit 18* advance. I would still not go below 14* and see how much boost that will allow you to run.

 

[fourreGsixty3]

As far as I know, carbon is a relatively good insulator, which, in turn should cause hotspots possibly. But thats just speculation.

And it appears as if that is the same question, just asked differently. Thanks.

Yes, it is a good insulator, and a good heat conductor. We both stated the samething in different ways HAHA. Yes it does cause hotspots. AND one of the reasons why carbon build up isnt wanted.

[QUOTE2gGSX]Furthermore, Matt (dsm-onster) already stated that retarding timing does not increase the heat of combustion in the cylinder, only in the exhaust track. This would make sense, since if it increased the heat of combustion you would actually GAIN power from retarding timing since the combustion charge would expand more under the higher level of heat, which would create a greater force on the pistons/bottom end.
[/QUOTE]

Yes this is very true. BUT with a larger turbo retarding the timing to increase heat in the exhaust manifold will help spool time, and make power...but it a different way of doing it. This really applys with large turbos so it doesnt really apply here

 

[Denji]

Do you realize that he has a 2g and starts off at having 16* peak timing advance? What you're telling him to do almost doesn't make sense--pull timing to run more boost, but stay above 15* advance. That 1 degree of timing will likely not allow him to run giant amounts of boost on a 16g of all turbos, which is already known to create high intake charge temps.

Furthermore, Matt (dsm-onster) already stated that retarding timing does not increase the heat of combustion in the cylinder, only in the exhaust track. This would make sense, since if it increased the heat of combustion you would actually GAIN power from retarding timing since the combustion charge would expand more under the higher level of heat, which would create a greater force on the pistons/bottom end.

Thats unusual because I'm getting 18 and 19 regularly on my timing with no changes to timing at all. I haven't touched timing yet.

Also, i realize now that I was doing my compression test without the car warmed up.

 

[2gGSX]

It's possible then that you aren't on the highest timing map. How does ECUplus handle fuel compensation? Does it adjust the map itself or is it a piggyback method where it hides airflow?

 

[Denji]

It's possible then that you aren't on the highest timing map. How does ECUplus handle fuel compensation? Does it adjust the map itself or is it a piggyback method where it hides airflow?

I'm not particularly sure what your asking about the highest timing map, without altering my timing, i'm logging between 17-19 timing at the top of my gears at WOT.

It does hide airflow by altering signal from MAS.

Maybe i misunderstood what was meant by 16 timing or something.

 

[turboglenn]

I'm not particularly sure what your asking about the highest timing map, without altering my timing, i'm logging between 17-19 timing at the top of my gears at WOT.

It does hide airflow by altering signal from MAS.

Maybe i misunderstood the 16 timing or something.

Sounds like the goold ol "AFC syndrome" There was a link on here that had a great write up and a graph to show how hiding air from teh stock ECU can cause it to use a different timing curve that's meant for lower air flow areas.


Hopefully some one can put a link to it in here, As i don't remember where i saw it.

 

[Denji]

Yes, it is a good insulator, and a good heat conductor. We both stated the samething in different ways HAHA. Yes it does cause hotspots. AND one of the reasons why carbon build up isnt wanted.

[QUOTE2gGSX]Furthermore, Matt (dsm-onster) already stated that retarding timing does not increase the heat of combustion in the cylinder, only in the exhaust track. This would make sense, since if it increased the heat of combustion you would actually GAIN power from retarding timing since the combustion charge would expand more under the higher level of heat, which would create a greater force on the pistons/bottom end.

A good insulator is always a bad heat conductor though, being a bad heat conductor is the actual physical property that defines an insulator.

 

[2gGSX]

I'm not particularly sure what your asking about the highest timing map, without altering my timing, i'm logging between 17-19 timing at the top of my gears at WOT.

It does hide airflow by altering signal from MAS.

Maybe i misunderstood what was meant by 16 timing or something.

The ECU has different timing "maps" for different load levels (given in g/rev). The highest timing map is when you exceed 2.1 g/rev. With your timing of 17-19 at the top of the gears, I'd assume that you were between 1.8 and 2.1 g/rev. The fact that your ECUplus hides airflow from the MAS is why your ECU is seeing the decreased g/rev, and thus putting you on lower timing.

 

[Denji]

The ECU has different timing "maps" for different load levels (given in g/rev). The highest timing map is when you exceed 2.1 g/rev. With your timing of 17-19 at the top of the gears, I'd assume that you were between 1.8 and 2.1 g/rev. The fact that your ECUplus hides airflow from the MAS is why your ECU is seeing the decreased g/rev, and thus putting you on lower timing.

What kind of timing should i be seeing then?

I feel it could also be because I'm doing 2nd gear pulls, I was told today i should do 3rd gear pulls.

Likewise, thats all the timing i saw before fuel adjustments were even made.

 

[2gGSX]

Third gear pulls are a much better alternative, as most people do not see full load in second gear. When you say that no fuel adjustments were made, are you saying that those were on 450cc injectors or that no fine tuning fuel adjustments were made?

Post up a log including g/rev, or at least RPM and airflow. If you have different fuel settings, then post those up as well.

 

[Denji]

Third gear pulls are a much better alternative, as most people do not see full load in second gear. When you say that no fuel adjustments were made, are you saying that those were on 450cc injectors or that no fine tuning fuel adjustments were made?

Post up a log including g/rev, or at least RPM and airflow. If you have different fuel settings, then post those up as well.

On 450s at low boost i saw only 19 timing advance in second gear with no adjustments using ecuplus as a logger only.


Do you want a JPeg image or a ecuplus file?

 

[2gGSX]

Is there any way to export the data into a text format? If not, the ECUplus file will do, assuming their software is free.

 

[Denji]

Is there any way to export the data into a text format? If not, the ECUplus file will do, assuming their software is free.

The software is a free download at the ecuplus site. I dont know what all i logged but here it is.

The file is uploaded as log.doc so make sure you change it to log.ecd to be opened with the ecuplus software. Thanks for all your help. Also, if anyone knows what timing i SHOULD have on a 2g please let me know.

One labeled log is on 550cc injectors and with wideband
One labeled 450log is on 450cc without wideband