Ignition Timing and Horsepower

[Myx]

In our 1.5ltr turbo application, how much is +1 degree of ignition timing advance worth in horsepower? This is with all else being equal (Temps, air/fuel ratio, boost pressure, etc).




Personal Notes Below on Ignition Advance in what gears: Please Disregard
Gear - Ignition (All 21.5psi@WOT)

Ktuner Stage 2
2nd Gear - 1
3rd Gear - 0
4th - 0

TSP Stage 1
2nd Gear - 3.5
3rd Gear - 2.5
4th - 2.5

Drob Custom Tune - (93 Octane)
2nd Gear - 5.5
3rd Gear - 4.5
4th - 4

Boostane Premium Octane Booster - Drob Custom
2nd Gear - 7
3rd Gear - 5.5
4th - 5.5

Boostane Pro Tune (Myxal Tune)
2nd Gear - 7.5
3rd Gear - 7
4th - 6

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[Hollywoo0220]

Where do you intend to increase the timing? The intitial timing, mechanical, or vacuum?
Honestly, if you are on a CAN tune (e.g. TSP Stage 1) then, I am certain that DRob did his math and set the correct TDC for that particular PSI & Octane.
I will say this:
As long as you are not increasing the PSI (which generates more heat) and you are not "knocking", then Advancing the Ignition might take you out of MBT.
Help?

**Basically you want just enough timing to keep you in the optimum MBT so that you can make power as the RPM increases and the fuel burns off more rapidly.

 

[Myx]

Where do you intend to increase the timing? The intitial timing, mechanical, or vacuum?
Honestly, if you are on a CAN tune (e.g. TSP Stage 1) then, I am certain that DRob did his math and set the correct TDC for that particular PSI & Octane.
I will say this:
As long as you are not increasing the PSI (which generates more heat) and you are not "knocking", then Advancing the Ignition might take you out of MBT.
Help?

**Basically you want just enough timing to keep you in the optimum MBT so that you can make power as the RPM increases and the fuel burns off more rapidly.

I want to keep this simple. At peak horsepower, if you were to increase timing by one degree (+1), without changing anything else and all else being equal (Fuel quality, boost psi, inlet air temp, etc) AND you experience no knock, how much would this equal too in horsepower? In our application (1.5ltr turbo Civic). I understand results could be different on say an N/A V8 Camaro/Mustang for instance.

 

[D-RobIMW]

This question doesn't have a simple answer.

You can advance ignition and not pick up any power if you have enough octane, just like you can advance too far and lose power before hitting a knock condition.

 

[charleswrivers]

Well... I’m following a tough act.

I will say what little I’ve gleaned. The Ktuner 23# basemap has an ethanol enable option if you use flex fuel which adds a percentage of an ethanol advance table based on the amount of ethanol the flex fuel sensor sees... maxing out at around E35 as memory serves (might be a little off and fusing knowledge between it and TSP Stage 2).

You can compare the plain-Jane 23# basemap and extrapolate the amount of power the timing advance table gave. It’s maximum advance value it provides is “+5”. There may be some things ethanol does beyond having higher octane... cooling the intake charge more since it flashes more readily... and also needing more fuel volume which provides some cooling. I’m not sure if ethanol itself burns and creates pressure in the engine a little differently too... which in turn effects how torque is generated. If one were to make a linear interpretation, you’d spitball “10 whp per degree” from the comparison of the two dynos. It is, however... not linear.

I’ve read and seen some threads on other cars that show how cars that use high octane fuel to to not be so knock limited and have diminishing returns when advancing timing... then reach a point they essentially do nothing... then power starts to drop. I wish I have saved those off-site threads... but there’s some good threads that exist showing 1-2 degree change w/dynos to show the difference. There’s also a lot more with getting the AFRs right and balancing boost on a FI car... with airflow being limited on undersized turbos (like ours) for high power goals and how it’s better to nab some timing over just dumping hotter, higher pressure air that’ll only serve to drive you closer to knock but w/o any more power.

So it seems like the short answer is, ‘an amount that diminishes the more you add... and will be negated once you increase it to the point k.cont rises and pulls what’s timing you tried to add... and something possibly close to the the gap you’d bridge on the Ktuner 23# w/ethanol table enabled per linear extrapolation, but certainly not more.’ I know there was some folks running a 23# basemaps with a couple extra degrees. I was at one time. There are others that got rid of the taper and tried to run over 23#... something like 25# but found they couldn’t do more than a degree or two w/o k.cont screaming up. I have to assume that @D-RobIMW, using the TSP Stage 1 that essentially *matches* a Ktuner 23# basemap running E35 is just about the bleeding edge of what you can do on 91/93 octane gasoline while still holding a safety margin for a not-custom tune. The fact we, percentage-wise have huge peak torque gains and more modest horsepower gains are telling as to how undersized the turbo is for making more power.

Disclaimer: From a total layman who’s just done a lot of reading... that ought to come across clear as mud. The heavy-tuners experience trump the heavy-readers understanding-through-reading... as they should. Happy as hell I have had my TSP Stage 1 tune. Running since 7/31/18 without a hiccup.

Off topic... I thought you had one of those Depo intercoolers if I remember right. I was eyeing 27Wons intercooler... god it looks good... and given how limited the stock turbo is, the lower IATs coupled with the lower pressure drop and greater cold-side volume from different piping looks like it really might make a good difference on a stock turboed car. You’d picked up a few mph trap. I was thinking that skyway run at Fontana and how the car was breathing hard under a lot of sustained heavy boost.

... then again, I think I’ll be skipping the intermediate group and go with the relaxed one this year.

 

[gtman]

Myx, I guess I'm confused here. It sounds like you're considering some self-tuning? If you're interested in eeking out some more power safely, why not have D-Rob do the work?

Or are all your recent inquiries about cylinder fill limits, knock air limits, timing etc. just hypothetical?

Everything I've seen/read tells me self-tuning may be a recipe for problems.

 

[Myx]

Thanks for your replies. My only experience with this is when I was in my dyno'ing days (getting old man) and I was testing this very thing on my old 1989 OHC 2.7ltr Subaru XT6 (N/A). I kept turning the disty to get one extra timing advance then dyno'ing again. I'd gain a little more horsepower/torque up until about +10 degrees and the curve got smoother each time but after +10 I wouldn't gain anymore hp. So that's where I left it. Times have changed though and I haven't ran a dyno for what seem like centuries now. (They used to let me do it because I practically lived there...Xotic Motorsports).

So I asked!

 

[Myx]

Myx, I guess I'm confused here. It sounds like you're considering some self-tuning? If you're interested in eeking out some more power safely, why not have D-Rob do the work?

Or are all your recent inquiries about cylinder fill limits, knock air limits, timing etc. just hypothetical?

Everything I've seen/read tells me self-tuning may be a recipe for problems.

I'm not self tuning. Drob is 'cooking' up something from an idea I'm testing. My curiosity on this was killing me though. I've read (and still is) about this on other platforms. Was just curious!

 

[charleswrivers]

I'm not self tuning. Drob is 'cooking' up something from an idea I'm testing. My curiosity on this was killing me though. I've read (and still is) about this on other platforms. Was just curious!

Well, I did do a very little ‘self tuning’ and really enjoyed it. When Drob came out with TSP Stage 1... I jumped ship to that because I knew I’d never get as much power fooling around as what a real tuner could accomplish... not to mention to amount of test time he did on his mule before it was released to the public.

There was actually a place w/a dyno in town I was going to try out and it went out of business in a few months between me asking if they could tune my Z (they couldn’t) and me calling about the Civic. I’ve pretty much given up on ethanol... and I’m not ready to chuck the stock turbo. An intercooler is intriguing. I like the power the car makes in the cool months, but it leaves me wanting in the summer months.

 

[Myx]

There was actually a place w/a dyno in town I was going to try out and it went out of business in a few months between me asking if they could tune my Z (they couldn’t) and me calling about the Civic. I’ve pretty much given up on ethanol... and I’m not ready to chuck the stock turbo. An intercooler is intriguing. I like the power the car makes in the cool months, but it leaves me wanting in the summer months.

Keep the stock turbo but man....with that TSP tune, an intercooler makes a difference. Not gonna lie, I couldn't tell by the seat of my pants. I never can tell a difference with anything anymore unless lowend torque is ridiculous. But I took my car to the track and it made as significant and measurable difference. Same track, same week, similar temperatures. See POST #19 I never really recommend anything on the forums but if you have an aftermarket tune on the stock turbo, I recommend getting an aftermarket intercooler of your choice. I went with Depo because it was cheap and I read a lot of good reviews on them (Posted links in the same thread). I was ready to order a PRL the next day and it was on backorder. In my impatience, I ordered the Depo Racing one that night after reading the reviews on other forums.

 

[fenix-silver]

Off topic... I thought you had one of those Depo intercoolers if I remember right. I was eyeing 27Wons intercooler... god it looks good... and given how limited the stock turbo is, the lower IATs coupled with the lower pressure drop and greater cold-side volume from different piping looks like it really might make a good difference on a stock turboed car. You’d picked up a few mph trap. I was thinking that skyway run at Fontana and how the car was breathing hard under a lot of sustained heavy boost.

Agreed on that 27won IC. Looks like a really nice piece of kit that could really help in the summer months.

 

[Myx]

Well... I’m following a tough act.

I will say what little I’ve gleaned. The Ktuner 23# basemap has an ethanol enable option if you use flex fuel which adds a percentage of an ethanol advance table based on the amount of ethanol the flex fuel sensor sees... maxing out at around E35 as memory serves (might be a little off and fusing knowledge between it and TSP Stage 2).

You can compare the plain-Jane 23# basemap and extrapolate the amount of power the timing advance table gave. It’s maximum advance value it provides is “+5”. There may be some things ethanol does beyond having higher octane... cooling the intake charge more since it flashes more readily... and also needing more fuel volume which provides some cooling. I’m not sure if ethanol itself burns and creates pressure in the engine a little differently too... which in turn effects how torque is generated. If one were to make a linear interpretation, you’d spitball “10 whp per degree” from the comparison of the two dynos. It is, however... not linear.

I’ve read and seen some threads on other cars that show how cars that use high octane fuel to to not be so knock limited and have diminishing returns when advancing timing... then reach a point they essentially do nothing... then power starts to drop. I wish I have saved those off-site threads... but there’s some good threads that exist showing 1-2 degree change w/dynos to show the difference. There’s also a lot more with getting the AFRs right and balancing boost on a FI car... with airflow being limited on undersized turbos (like ours) for high power goals and how it’s better to nab some timing over just dumping hotter, higher pressure air that’ll only serve to drive you closer to knock but w/o any more power.

So it seems like the short answer is, ‘an amount that diminishes the more you add... and will be negated once you increase it to the point k.cont rises and pulls what’s timing you tried to add... and something possibly close to the the gap you’d bridge on the Ktuner 23# w/ethanol table enabled per linear extrapolation, but certainly not more.’ I know there was some folks running a 23# basemaps with a couple extra degrees. I was at one time. There are others that got rid of the taper and tried to run over 23#... something like 25# but found they couldn’t do more than a degree or two w/o k.cont screaming up. I have to assume that @D-RobIMW, using the TSP Stage 1 that essentially *matches* a Ktuner 23# basemap running E35 is just about the bleeding edge of what you can do on 91/93 octane gasoline while still holding a safety margin for a not-custom tune. The fact we, percentage-wise have huge peak torque gains and more modest horsepower gains are telling as to how undersized the turbo is for making more power.

Disclaimer: From a total layman who’s just done a lot of reading... that ought to come across clear as mud. The heavy-tuners experience trump the heavy-readers understanding-through-reading... as they should. Happy as hell I have had my TSP Stage 1 tune. Running since 7/31/18 without a hiccup.

Off topic... I thought you had one of those Depo intercoolers if I remember right. I was eyeing 27Wons intercooler... god it looks good... and given how limited the stock turbo is, the lower IATs coupled with the lower pressure drop and greater cold-side volume from different piping looks like it really might make a good difference on a stock turboed car. You’d picked up a few mph trap. I was thinking that skyway run at Fontana and how the car was breathing hard under a lot of sustained heavy boost.

... then again, I think I’ll be skipping the intermediate group and go with the relaxed one this year.

I never did thank you for posting this very detailed information. My general thinking was about 10hp per degree of advance per other car forums I have been reading but this was on bigger engines. I am thinking of this in line as to advancing the ignition, while not getting any knock (or significant k.count). Thanks for the post! I tend to read and re-read a lot of information and posts on this site. Over and over again!

 

[charleswrivers]

Knocking the dust off this one:

I have an ethanol kit in the mail. I happened to win it and have been up in the air on keeping it or passing it along. A new gas stationed opened less than 3-4 miles from my house that has E85 (better than the ~20 of the previous closest) that also opens the door for a close/convenient source.

I’ve looked at Ktuner ethanol enable basemap and the juice is not worth the squeeze when comparing it to TSP Stage 1. They’re so close that I imagine there’d be no noticeable difference.

Looking at the flavor of basemap and enable Hondata runs, their car roughly match midrange torque but make a good bit more power up top. I do not know if they also have the same 23 to 21# boost taper as well that I have removed previously on just modding a plain jane Ktuner 23# basemap.

Looking a little deeper, from memory the ethanol enable table for Ktuner’s 23# basemaps uses a maximum value of 5. It appears that Hondata’s version well exceeds that at 8. Both have another multiplier table for implementing full advance based on lower ethanol percentages

~25 whp over TSP stage 1 is somewhat intriguing. The massive torque made in TSP Stage 2’s midrange and the seeming sharp power drop off up top isn’t that desirable (peak power is at 5000 RPM).

Anyone ever use a Ktuner 23# basemap and modify the ethanol tables to match Hondata’s values? I thought I’d heard of folks shooting in the 10 range a long time ago but can’t recall the threads I was in. I know the fallacy at comparing different dynos and different cars and I’m not sure if some of the tuning is apples to oranges between devices... but I thought there may be something to those differences and Hondata does appear to use higher values.

I guess in the end, I’m wondering if it’s worth fooling with ethanol on a stock turbo car with a gentled midrange (stay well under 300 ft-lbs) to limit peak torque while being able to find noticeable greater power from 4500-6500 RPM. If just using Hondata’s numbers could yield a ~20 whp bump over a TSP stage 1... I’d think yes... but the stage 2 always looked super soft up top to me. Softer than a Hondata ethanol enable... and that’s where I want to have my fun.

The other option is to bite the bullet, flip the ethanol kit and maybe get a W1 turbo on Black Friday for <1k out-of-pocket. Now that I’m pretty settled on keeping the Si, I’d like to get a bit more umph out of it up top for a bit peakier and fun experience up there. The idea of messing with basemaps (I have been again with the 23# basemap) has my interest as well.

 

[arnoldo]

I am on Hondata Flashpro so we obviously have different way of tuning ignition. Hondata doesn't open ignition timing tables. They only open Knock Ignition Limit table for ignition adjustment.

If I try to translate Hondata Flashpro to KTuner, my knock ignition limit would look like this (22 PSI):
2nd Gear - 4
3rd Gear - 3
4th Gear -2.5

This conversion is based on datalog run and datalog examination. The ignition advance of the actual ignition may not be accurate because I only get access to Knock Ignition Limit Low table to adjust ignition timing.

 

[charleswrivers]

Hondata doesn't open ignition timing tables. They only open Knock Ignition Limit table for ignition adjustment.

Interesting. I’ve never had a Flashpro. I was looking at Hondata’s page and thought ignition timing, at least the ethanol advance maps were open based on this:

https://www.hondata.com/help/flashpro/index.html?ethanol_tuning.htm

That’s what I saw that had seemingly higher values I though might account for the greater claimed power. I know I’m on shaky ground comparing different cars on different dynos... but when it looked like they were using greater ignition advance, I thought it might be making the difference. Ktuner has the base ignition map, an ethanol advance map (the one I thought Flashpro was showing was open and possibly an equivalent) and then the table that controls the % implementation based on ethanol concentration. I’ve never used ethanol previously, but have added +1 to a upper portion of the ethanol basemap while running 93.

Thanks for the info. I’ve got more reading to do.

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