Dano's Boost Tuning 101 + Cool Stuff

[amoosenamedhank]

You have expectations now nucker....

[Frequentflyer]

Here's my current map. I am working on another one, but just haven't gotten around to it lately.

[djuosnteisn]

Welp...... I'm hooked.



Tuned a buddy last night with boost based. And all i can say is.... shit that was ridiculously easy lol.

ECU is so much faster at controlling any boost transients. My only guess as to why is simply less latency in the processor. To mitigate an over"load" situation, the ecu must first read in half a dozen sensors... MAF, MAP, IAT, BATs, BARO.... etc etc.. Then Head to a look up table to convert the MAF voltage to a g/s... Then throw all the sensor data into a fairly extensive calculation to get load. Then it has to look up what the target load is (which consists of looking at several table values and determining which one to target, cause we have multiple load tables)... then it can finally determine the error in load, and make a change to the WGDC and/or throttle position. Then it has to do it all over again.

With boost based tuning... ECU simply reads one sensor... the MAP. Then looks at one table... Boost targets. Then calculates error and tweaks WGDC.


I was a doubter about the true benefits before lol... but after getting to do one in person, i'm a changed man lol. The car was amazingly well behaved.


We didn't spend a lot of time on the gear control... so it may have been working. I modified both A & B tables (for gear 1-2) with a gradual increase.

We'll play around more tomorrow i'm sure. Also going to tune another 1 or maybe 2 cars tomorrow as well, and i'll certainly be using BBC lol.

[Dano]

hahaha

yes it does rule

i came up with the same conclusion as to why boost based is faster reacting...think I covered it earlier in this thread....but yeah, ECU only has to read one sensor and very little calculation needed to alter DC to reach target.

Glad to here it has the DJ stamp of approval!

[DSIT995]

Ugh, Ive driven about .2 miles in past month.... Cant wait any longer to get out and try out this new map. (havnt really tried out my Boost based map much)

CT sux in the winter

[Fobio]

can you guys elaborate on your findings with per gear boost control? and how to manipulate it?

EDIT: Here are some of my street logs from tonight...-8*C weather.

[Dano]

I will have some data posted this afternoon but I am currently running .75 % compensation in 1-3rd gears in both A and B tables from 2250 to 5.5K. This does need some work still which I hope to get to today.

A tables work for 1 and 3rd but for some reason it takes the B table to limit boost in 2nd gear WTF. I would like to know if this is the case with other cars.

[Frequentflyer]

I believe the gear based compensation is more for adjusting for different loads in specific gears than it is for traction control. We still have the DBW tables for traction control. The ECU shouldn't be trying to achieve traction by reducing WGDC. It's much quicker to close the throttle and kill two birds with on stone.

[Dano]

That sounds good on paper but I'm not sure adjusting DBW will work to achieve our goals.

how do you plan to implement gear based throttle control with DBW? We only want less power in the lower gears and adjusting DBW will effect all gears.

Maybe you mean APP translation instead?

We are not directly trying to control traction with Boost Comp but rather indirectly control traction by limiting boost in specific gears.

APP definitely worked and I am still working on Boost comp and haven't made a final decision, but at face value, Boost Comp looks like a better choice and easier to implement than APP. In my experience, APP was fairly difficult to get adjusted without adversely effecting pedal feel. you only want to modify from about 50% up.

[Lex]

Originally Posted by djuosnteisn Welp...... I'm hooked. Tuned a buddy last night with boost based. And all i can say is.... shit that was ridiculously easy lol. ECU is so much faster at controlling any boost transients. My only guess as to why is simply less latency in the processor. To mitigate an over"load" situation, the ecu must first read in half a dozen sensors... MAF, MAP, IAT, BATs, BARO.... etc etc.. Then Head to a look up table to convert the MAF voltage to a g/s... Then throw all the sensor data into a fairly extensive calculation to get load. Then it has to look up what the target load is (which consists of looking at several table values and determining which one to target, cause we have multiple load tables)... then it can finally determine the error in load, and make a change to the WGDC and/or throttle position. Then it has to do it all over again. With boost based tuning... ECU simply reads one sensor... the MAP. Then looks at one table... Boost targets. Then calculates error and tweaks WGDC. I was a doubter about the true benefits before lol... but after getting to do one in person, i'm a changed man lol. The car was amazingly well behaved. We didn't spend a lot of time on the gear control... so it may have been working. I modified both A & B tables (for gear 1-2) with a gradual increase. We'll play around more tomorrow i'm sure. Also going to tune another 1 or maybe 2 cars tomorrow as well, and i'll certainly be using BBC lol.

The processor is plenty fast at reading those values - however you have several related variables to control when load tuning including boost and load. The reason the system responds so much faster is because the control system has been reduced in terms of numbers of inputs and outputs. Splitting hairs here but it's not processing power, it's the complexity of the control system that has changed.

I will try this out once it dries out here since now all I get is spin.

[Frequentflyer]

Originally Posted by Dano2010 That sounds good on paper but I'm not sure adjusting DBW will work to achieve our goals. how do you plan to implement gear based throttle control with DBW? We only want less power in the lower gears and adjusting DBW will effect all gears. Maybe you mean APP translation instead? We are not directly trying to control traction with Boost Comp but rather indirectly control traction by limiting boost in specific gears. APP definitely worked and I am still working on Boost comp and haven't made a final decision, but at face value, Boost Comp looks like a better choice and easier to implement than APP. In my experience, APP was fairly difficult to get adjusted without adversely effecting pedal feel. you only want to modify from about 50% up.

What I'm saying is that I think the ECU uses the DBW tables (the B table to be exact) to control traction. When it senses slip, it reverts to the lower values in the DBW B table and closes the throttle. I don't think it matters what gear we're in. In the past we have used the load based gear tables to tune out traction issues per gear, but what each of these tables was designed for is really up to Cobb's research, interpretation and of course our tinkering.

[Fobio]

Originally Posted by Lex The processor is plenty fast at reading those values - however you have several related variables to control when load tuning including boost and load. The reason the system responds so much faster is because the control system has been reduced in terms of numbers of inputs and outputs. Splitting hairs here but it's not processing power, it's the complexity of the control system that has changed. I will try this out once it dries out here since now all I get is spin.

I have always believed in the theory that some of the things we're doing is dumbing down the ECU, but then again, form follows function, so I don't really need aesthetically pleasing code, but taking advantage of what the ECU can do rather than lmiting what it does to get to a certain end would be ideal.

[Dano]

Originally Posted by Frequentflyer What I'm saying is that I think the ECU uses the DBW tables (the B table to be exact) to control traction. When it senses slip, it reverts to the lower values in the DBW B table and closes the throttle. I don't think it matters what gear we're in. In the past we have used the load based gear tables to tune out traction issues per gear, but what each of these tables was designed for is really up to Cobb's research, interpretation and of course our tinkering.

oh, I see what you mean now...LOL

I suppose that could work...that is if everyone doesn't immediately disable DSC when they start the car like I do

I wonder though what other tables the ECU switches to when traction is lost and those other tables might need tweaking as well to keep from losing all power when traction is lost.

For me, i want to tune the car so that at WOT it WILL lose traction but just barely so that slight throttle modulation by me will keep it under control, not something the ECU decides to do...LOL

Originally Posted by Fobio I have always believed in the theory that some of the things we're doing is dumbing down the ECU, but then again, form follows function, so I don't really need aesthetically pleasing code, but taking advantage of what the ECU can do rather than lmiting what it does to get to a certain end would be ideal.

if only we knew for sure what all the logic was within the ECU, we could then leverage it to our needs. As it is, it seem better to dumb down parts of the ECU to achieve our goals until said logic is uncovered. This is of course just my opinion

[Frequentflyer]

We all know that the factory tuned limits boost in 1st and 2nd gears. How? I don't know. I'm not particularly sold on the idea that this was done through the throttle request load gear tables. I don't know. Maybe it was.

I tend to drive with my traction control on all the time and I find that it works a lot better in the wet/ice/snow than it does on dry pavement. It might programmed to react more from the rate at which the tires break loose, but I know that if I hammer it in 1st gear, the traction control barely does anything at all to control wheel spin and I'm only seeing about 13-14 psi in first gear to begin with. From what I saw playing with the boost comp by gear tables, it did react to lower numbers and I was seeing boost as low as 10 psi in first gear so maybe that is the direction we should be heading. I am not sure whether it applies those tables before or after temp compensation or if that even matters. With all the snow and shitty whether recently, I haven't bothered to mess around with it, but I did get my timing bumped up to around 10 degrees and saw 292 g/s peak with warmer outside air temps, so I think I picked up a few horses there.

[Lex]

^ I upped my timing 2-3 degrees along with enabling the knock sensor to 6750 and the car is much more willing. Timing is everything

[Dano]

Originally Posted by Lex Timing is everything

hahah

that's what they say. Esp with women and cars...

I am up to a conservative 13* at 6.5K. Up from 10 and it is a night and day difference. It still requires 5050 WMI to keep KR at bay. I think Driver said he runs more without WMI but you can't trust what that guy says

[Lex]

Originally Posted by Dano2010 hahah that's what they say. Esp with women and cars... I am up to a conservative 13* at 6.5K. Up from 10 and it is a night and day difference. It still requires 5050 WMI to keep KR at bay. I think Driver said he runs more without WMI but you can't trust what that guy says

I'm just having lots of traction issues at this point. It's wet and rolling into 3rd is nothing but spin. Makes it rather frustrating.

[Fobio]

Originally Posted by Lex I'm just having lots of traction issues at this point. It's wet and rolling into 3rd is nothing but spin. Makes it rather frustrating.

one night, I mashed 3rd, thinking it was 4th and I light up the tires...lol...I thought I had uber boost in 4th for a moment...

I think my timing has been "optimized" up top...I need meth.

[djuosnteisn]

Originally Posted by Dano2010 hahah that's what they say. Esp with women and cars... I am up to a conservative 13* at 6.5K. Up from 10 and it is a night and day difference. It still requires 5050 WMI to keep KR at bay. I think Driver said he runs more without WMI but you can't trust what that guy says

I'd love to see your injector seals. I'm on a heavy seal trip lately, if it's not obvious.

[Dano]

so you be thinkin my KR is actually seal popping?

it goes away with WMI at the same PSI.

[m4tic]

i have another question.. i have started a new boost tune map
set my BT, BD
set my OL wot fuel to ~11.8/11.9 taper to 11.5@ 6k
set CL\OL to 1.25/100%

in all my no knock fuel tables, where the cells were under 11.9, i set them to 11.9

my problem is this, im cruising down the freeway at , say, 70mph. my actual afr is showing 14.7, i let off the gas and coast for a second at 29+afr (ya normal). ok check this, if it barely put my foot on the gas to maintain speed my AFR will drop from 29(coasting) to 13.4(maintain speed) and if i give the gas pedal a little more nudge it will roll back up to 14.7

how do i get it to not drop past 14.7
do i need to sku maf/gs up in that area?

what gives

[djuosnteisn]

Originally Posted by Dano2010 so you be thinkin my KR is actually seal popping? it goes away with WMI at the same PSI.

Yeah, possibly not. And it goes away when you pull a bit of timing, right?


I just wonder though.....

I mean seals pop with increases of power, and they get worse with time. Pulling timing is reducing power... and the wmi may be reducing power as well (who knows... sometimes you have to tune for it).

It's all speculation, but i'm starting to think more and more that the seals are causing majority of kr. The amount of spark advance we target seems insanely low compared to most other platforms. And some may say it's cause of DISI and better atomization, and that may be true... but i just dunno at this point lol.


We'll know more as people start to upgrade the seals and retune. But they are definitely a weak link.

[Lex]

Originally Posted by bmorrisj i have another question.. i have started a new boost tune map set my BT, BD set my OL wot fuel to ~11.8/11.9 taper to 11.5@ 6k set CL\OL to 1.25/100% in all my no knock fuel tables, where the cells were under 11.9, i set them to 11.9 my problem is this, im cruising down the freeway at , say, 70mph. my actual afr is showing 14.7, i let off the gas and coast for a second at 29+afr (ya normal). ok check this, if it barely put my foot on the gas to maintain speed my AFR will drop from 29(coasting) to 13.4(maintain speed) and if i give the gas pedal a little more nudge it will roll back up to 14.7 how do i get it to not drop past 14.7 do i need to sku maf/gs up in that area? what gives

Is your car in closed loop when you just touch the gas? It should be and that means the O2 feedback should bring you back to 14.7. Check if you're in closed loop.

Originally Posted by djuosnteisn Yeah, possibly not. And it goes away when you pull a bit of timing, right? I just wonder though..... I mean seals pop with increases of power, and they get worse with time. Pulling timing is reducing power... and the wmi may be reducing power as well (who knows... sometimes you have to tune for it). It's all speculation, but i'm starting to think more and more that the seals are causing majority of kr. The amount of spark advance we target seems insanely low compared to most other platforms. And some may say it's cause of DISI and better atomization, and that may be true... but i just dunno at this point lol. We'll know more as people start to upgrade the seals and retune. But they are definitely a weak link.

They seem to be a wear over time item as well with injector vibrations ... so the seal becomes poorer with mileage. It's a really poor design as it also seems to eat into the head. Did you blow yours D?

[djuosnteisn]

Yup. On my last setup. I was one of the first beta testers for SD. Seals are still in right now, and i'm itching to turn up the boost.

I'm 90% sure super skater's are on the way out as well. And another guy i'm tuning (stock turbo).


I swear... our cars love a lil added timing, and the power really comes alive... but seems like it may be one of the causes of seal failure. I'm not for sure quite yet. Might just be circumstantial.


But i find myself telling people i tune "you might want to think about getting some seals when they're available"... almost as much as i say "you need a fuel pump", lol.

[Lex]

Originally Posted by djuosnteisn Yup. On my last setup. I was one of the first beta testers for SD. Seals are still in right now, and i'm itching to turn up the boost. I'm 90% sure super skater's are on the way out as well. And another guy i'm tuning (stock turbo). I swear... our cars love a lil added timing, and the power really comes alive... but seems like it may be one of the causes of seal failure. I'm not for sure quite yet. Might just be circumstantial. But i find myself telling people i tune "you might want to think about getting some seals when they're available"... almost as much as i say "you need a fuel pump", lol.

There was the one stock turbo 09 that lost its seals - any other stock turbo people blow the seals? Detonation creates higher pressure spikes than controlled combustion so knock becomes that much more relevant.

Originally Posted by Fobio one night, I mashed 3rd, thinking it was 4th and I light up the tires...lol...I thought I had uber boost in 4th for a moment... I think my timing has been "optimized" up top...I need meth.

How many miles/kms on your car Fobio?

[djuosnteisn]

Originally Posted by Lex There was the one stock turbo 09 that lost its seals - any other stock turbo people blow the seals? Detonation creates higher pressure spikes than controlled combustion so knock becomes that much more relevant. How many miles/kms on your car Fobio?

Popped Injector Seals with Stock Turbo

Here's the guy i tune. Seals remedied all our KR difficulties. We still haven't dialed the timing back up all that high... mostly cause he replaced his bad seals with more shitty oem seals, and we don't want to accelerate the next failure. If they become troublesome again, he'll upgrade to cp-e seals, but they're not quite available yet and he wanted to avoid damaging his injector bores.

There's a fair # of stock turbo guys who've blown seals, and quite a few chime-in in that thread. 3speedy (OP) was very very mildly bolted... But i think the cold temps perhaps played a role, as his car was running very well before we started chasing our tails on the KR.

[Dano]

Originally Posted by djuosnteisn Yeah, possibly not. And it goes away when you pull a bit of timing, right? I just wonder though..... I mean seals pop with increases of power, and they get worse with time. Pulling timing is reducing power... and the wmi may be reducing power as well (who knows... sometimes you have to tune for it). It's all speculation, but i'm starting to think more and more that the seals are causing majority of kr. The amount of spark advance we target seems insanely low compared to most other platforms. And some may say it's cause of DISI and better atomization, and that may be true... but i just dunno at this point lol. We'll know more as people start to upgrade the seals and retune. But they are definitely a weak link.

yes less timing = no kr but with more timing when I get KR it was only 1-2 and only around 5K. I don't want any above .7. ECU does protect the engine and inject more fuel and pull timing so its not that big a deal but I don't want to run around daily with that.

I like set and forget

[djuosnteisn]

Oh, i agree fully dano. That's definitely the right mentality. But if/when your seals further degrade... and you start getting KR at the current "acceptable" timing values, are you just going to continue to retard the timing? Or douse in more meth?

All i'm saying is that i've had a few recent situations that resulted in the seals being the cause for KR. Hence my original statement about betting your seals are probably part of your issue, and it's not genuine KR. Again, completely speculation.

Sorry for hijacking le thread lol.

[Dano]

n/p and if I need seals then I'll get them and no matter what, when I do an IM upgrade I'll replace all that weak sauce fueling stuff. Seals and HPRV.

My car really hasn't had much in the way of KR but then again I just recently started increasing timing above OTS values. no matter what it aint gonna be as bad as lenny's

[djuosnteisn]

Lenny has a very high mileage and abused motor lol. I wouldn't be surprised if he didn't even have seals left hahaha.

[Dano]

[cld12pk2go]

Just throwing out where I currently am with respect to ignition timing:

Current OL values:



Delta from stock:



Delta from aggressive Cobb basemap:

[djuosnteisn]

Not to shabby. I love to see 7 degrees at 4500, 9-10 at 5500, and 14-15 at redline... but you can't always hit those, and timing isn't something you force.

cld12, do you rely on the wmi to hit those targets? Can you draw a line showing your typical load values at the various rpms, so we can get a sense of where you operate?

[Dano]

since we are on the subject...below is an xls with some older values but you can see how I have indicated actual load values for my setup and temp.



Actually here are my current values a bit higher and 14 at 7K. Same load curve as the xls.

[djuosnteisn]

Not bad at all! You can increase timing more aggressively above 5500 rpm as the VE falls off as well. You saw my timing curve in my build thread, right? It was ridiculous lol. I'd like to see you hitting at least 14 at redline IMO.

[Dano]

edited my timing post with updated data. Closer to what you were wanting.

[djuosnteisn]

Looks like a great, fun, safe map man!

[Dano]

I'll have to keep an eye out as summer rolls around.

[cld12pk2go]

Originally Posted by djuosnteisn Not to shabby. I love to see 7 degrees at 4500, 9-10 at 5500, and 14-15 at redline... but you can't always hit those, and timing isn't something you force. cld12, do you rely on the wmi to hit those targets? Can you draw a line showing your typical load values at the various rpms, so we can get a sense of where you operate?

Yes, I am running a M7 nozzle with straight meth. My exhaust backpressure has to be insane with the stock turbo and stock TBE, which will certainly limit my timing advance potential.

I think my current timing is pretty close to optimized. I have added a good 3° or so up top since raising the KR threshold to 6700 RPMs.

Here is my most recent good log to redline:



In this case I sustained a pretty high load up top since the ambient temp was low. Mid 290 g/s isn't anything to sneeze at from the stocker (especially since it is really more than that since I am spraying so much meth and still hit my targeted AFR)...

I used to peak at 22 PSI around 3500-4500 RPMs, but my stock clutch won't take that in the cold so I am now targeting 18PSI until I can get my ACT installed (evidently the stock clutch doesn't respond well to loads > 2.3).

[m4tic]

do we have anything on per cylinder ign comp? also is there an easy way to make sure the ign max tables are above the ol/cl ign settings?