Tuning results from the weekend

[Black_Bullet]

Am wondering what I should class as the lowest boost I'll ever run. The way I drive, I am either off the turbo or just a few psi in, or I'm on WOT and so wanting as much boost as I can get. So should I try to preload the wastegate so that I get almost 1.5bar when the boost controller is off?

With the large spring and the small spring inside of it with my ebay knock off Tial 38mm, I get 20psi waste gate pressure with no mbc attached. I dont ever run under 20psi anyways so there was no need for me to get a lighter spring, especially since lighter spring pressure has proven to dampen the performance.

With me Im either just driving around like a old lady short shifting the car for gas milage, or Im driving hard wanting every last bit of power...

 

[soldave]

Well, I'm going to try a different actuator this weekend on the turbo and see if that makes any difference. The actuator in the Bullseye turbo seems to be a 10psi one which is a little low IMO. Have got a 19psi one I can use so will try to fit it and see what happens with that.

 

[bastarddsm]

Try that, It should help. My car has the same problem, I have a actuator off a 14b on my china gt 16G, and it dosn't have anywhere near the tension the factory 16g one had. However, it helps me as I am running up against fuel cut, and the boost falls as it just kisses it.

 

[soldave]

The car tuning saga goes on! Another weekend, another problem or 2 sorted out and another couple arising. First of all, I found out why the turbo wasn't holding more than about 1.3 bar/19psi of boost. Turns out the actuator on the Bullseye T04B 50-trim is only a 0.7bar/10psi actuator, so it really has trouble handling any boost higher than around 1.3bar/19psi. We switched the actuator to a 1.3bar/19psi one from a Slowboy turbo that had gone bad (at last - a use for SBR products!), and with a bit of actuator bracket fabrication we worked something out. Game on! We also Teflon taped the easily reachable bolts on the turbo although didn't have time to RTV the compressor housing this weekend.

So we went to do a few runs in an impromptu tuning session (4th gear pulls which are equivalent to DSM 3rd gear pulls given the Evo gear ratios, and from 2000rpm to redline) and with the boost controller turned off we were holding 1.32bar/19psi which was a nice start. Turning the boost controller up we got up to holding 1.56bar/23psi all the way up to redline with a spike up to 1.82bar/26psi which is a big improvement and means that an external wastegate might not be needed just yet. And a 0.2-0.3bar/3-4psi spike isn't too bad. The only problem with that was that knock was picking up. Will just note at this point that I'm running the 264 Comp Cams (basically the FP1x cams) which I love to bits, but which seem to be notorious for being knock-happy. When the turbo spools and spikes (at around 4200rpm) the knock kicks in and stays at the same level all the way up to redline. So at this point we were getting 11-13 counts of knock which was pulling timing. When we pulled the boost back to 1.5bar/22psi the knock was going down to about 5-7 counts and power was up.

As for the knock, I've got 3 possible solutions to try. Firstly, I am upping my meth content in my alcohol injection setup from a 50/50 meth/water mix to a 75/25 mix. That might make it handle the knock that develops from the initial boost spike. I am currently using an M10 meth nozzle and maybe I need to go up to an M12 to get enough meth in there to sort the knock out. And the last thing I could do is take a degree of timing out at around the 4500-5500rpm range (or maybe even 4500 all the way up to 8000 on my map) to see if that sorts things out. If that solution works and my knock counts drop to 0 or 1 then I might be able to add a little boost to compensate for the slight loss in power through timing. I've included the timing map below, which I haven't modified since tuning yesterday. And I know it's not a smooth curve but that's going to be sorted out later today when I sit down with my tuning laptop. On the timing map, load 1.0 represents no boost. The other figures refer to load values in vacuum and boost levels.

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Last couple of things to note is from the single launch I did when I was driving home and found a quiet bit of road. Launch control set to 5500rpm and I stayed on the gas a little longer than normal as boost built up. I ended up launching with about 10psi of boost and sent the tyres spinning like crazy all the way to the top of 1st. Hit 2nd hard and for a split second I might have felt my clutch slip before it all hooked up and sent me flying forward. I never thought I'd be happy to say I felt my clutch slip a little but it is a sign I'm making some good power. Looks like the days of the Centerforce super single might be numbered and a twin-plate setup could be on the Christmas or birthday list. As for the launch, while launching with 10psi of boost and spinning through 1st is nice, traction would be good too! Should I be satisfied with a little spinning through 1st gear or drop the launch control a little to try and get the point where I'm not spinning but not bogging?

Thanks as always for any comments

EDIT: One final thing from this weekend's tuning. The vacuum line that runs from the intercooler->throttle body pipe to my boost controller solenoid has its nipple close to the BOV. I have seen many setups where the nipple for the boost controller is on the compressor housing or very close to the turbo. Could this be a partial reason for the boost spiking (that by the time the boost controller detects the boost getting too high it's too late to do anything about it)?

Just a thought

 

[pneumo]

In general, shorter lines to and from the boost controller give faster response. A restriction in the line that feeds the boost controller, or a restrictive T fitting, or a small bleed hole in the boost controller can cause spikes.

When launching, a little spinning is just about perfect, but smoking the tires while bouncing off the rev limiter would be too much. Just a little spin.

When trying to cure knock by pulling timing, just remove timing where the knock goes up, or just before knock pops up. ECU code controls how fast the knock tapers down. If you're getting little spikes of knock during the whole pull, then the entire rpm range needs less timing, or other knock control.

 

[soldave]

The lines are as short as they can be, but that's not the issue I'm talking about here. The issue I am talking about that I thought of last night was the the nipple where the hose to the solenoid goes starts very close to the BOV outlet. Have seen some on or very close to the compressor housing and was wondering if that would be better in controlling the spike.

I didn't launch off the rev limiter, only the launch control set at 5,500rpm! So should I not launch at 100% throttle, bring the launch control level down, or what?

And the knock is starting at around 4,200-4,300rpm where the boost spools fully and starts to spike. The spike goes down but the knock count remain steady through the run in that gear.

 

[soldave]

Well it's Respect for the Aged day here in Japan, which means a public holiday for me. And what better way to show my respect for the old people in Japan and all around the world by doing some tuning and 3rd gear pulls in my car! I might have had some marginal success too, leaving out the first run where I had my boost controller set wrong and ended up boosting 2bar/30psi!

So my runs were in 3rd gear due to the length of the road I was doing testing on, and I was going from about 2500-3000rpm up to redline. Followed black bullet's advice and knocked a degree of timing out of the map at 4500 and 5000rpm. I managed to stop the knock at 4500rpm but no matter what I did I can't get rid of the knock that happens at about 5500rpm, even by taking 2 degrees of timing out. It does subside after spiking though which is something. I was also able to add a degree of timing in at the top end of the timing map (as you can see by the map below). I might be able to add another degree right at the top but I wanted to give my car some cooldown time before I could do that change. Maybe next time.

To compensate for the lack of timing at around 5500rpm now, I was able to up the boost a little bit. Now I'm holding boost at around 1.55bar/23-24psi with a spike to 1.76bar/26psi which I'm pretty pleased with, and peak power was up on the Rev/Speed Meter.

The changes I'm making with timing and a little fuelling are making tiny changes, but every little bit counts now. Knock counts are holding at 10 counts or less which is where I want them, and as you can see from the logs, the intake temps were high as I was doing plenty of runs. If I did the same runs in the evening I might be making even more power.

Will finish this update with my logs and a new timing map (which still has to be smoothed out as it's all over the place in parts). Let me know what you think.

Log in csv format

Time RPM Knock Timing Inj P/W Air Temp TPS Inj D/C
00:00.1 2281 0 18 4.62 149 100 8.78
00:00.2 2313 0 18 4.87 149 100 9.39
00:00.3 2313 0 18 4.87 149 100 9.39
00:00.5 2375 0 19 4.87 149 100 9.64
00:00.6 2438 0 19 4.87 149 100 9.89
00:00.7 2438 0 19 4.87 149 100 9.89
00:00.8 2469 0 19 4.87 149 100 10.02
00:00.9 2531 0 19 4.87 149 100 10.27
00:01.0 2594 0 20 4.87 149 100 10.53
00:01.1 2625 0 20 4.87 149 100 10.65
00:01.3 2656 0 20 4.87 149 100 10.78
00:01.4 2719 0 20 5.13 149 100 11.62
00:01.5 2781 0 21 5.13 149 100 11.89
00:01.6 2813 0 21 5.13 149 100 12.03
00:01.7 2875 0 21 5.13 149 100 12.29
00:01.8 2906 0 20 5.38 149 100 13.03
00:01.9 2938 0 21 5.38 149 100 13.17
00:02.0 3000 0 21 5.38 149 100 13.45
00:02.2 3031 0 21 5.64 149 100 14.25
00:02.3 3094 1 21 5.64 149 100 14.54
00:02.4 3156 1 21 5.64 149 100 14.83
00:02.5 3188 1 21 5.9 149 100 15.67
00:02.6 3250 1 21 6.15 148 100 16.66
00:02.7 3281 0 21 6.41 148 100 17.53
00:02.8 3344 0 20 6.67 148 100 18.59
00:02.9 3375 0 20 6.92 148 100 19.46
00:03.0 3438 0 20 7.18 148 100 20.57
00:03.1 3500 0 19 7.18 148 100 20.94
00:03.2 3563 0 17 7.44 148 100 22.09
00:03.3 3594 0 16 7.44 148 100 22.28
00:03.4 3688 0 15 7.69 146 100 23.63
00:03.5 3719 0 14 7.95 146 100 24.64
00:03.6 3781 0 13 8.2 146 100 25.84
00:03.7 3875 0 13 8.46 146 100 27.32
00:03.8 3906 0 12 8.46 146 100 27.54
00:03.9 3969 0 11 8.46 146 100 27.98
00:04.0 4063 0 11 8.72 145 100 29.52
00:04.0 4094 0 11 8.72 145 100 29.75
00:04.2 4156 0 11 8.72 145 100 30.2
00:04.2 4250 0 11 8.72 145 100 30.88
00:04.3 4313 0 11 8.97 145 100 32.24
00:04.4 4375 0 10 9.49 144 100 34.6
00:04.5 4469 1 10 9.49 144 100 35.34
00:04.6 4563 1 10 9.74 144 100 37.04
00:04.7 4625 1 10 10 144 100 38.54
00:04.8 4750 1 9 10.51 143 100 41.6
00:04.9 4844 1 9 10.77 143 100 43.47
00:05.0 4906 0 9 11.03 142 100 45.09
00:05.1 5031 0 10 11.54 142 100 48.38
00:05.2 5156 0 10 12.05 142 100 51.77
00:05.3 5219 2 10 12.31 140 100 53.54
00:05.4 5375 6 7 12.56 140 100 56.26
00:05.5 5469 10 8 12.82 139 100 58.43
00:05.6 5563 10 9 12.82 139 100 59.43
00:05.7 5719 9 10 12.56 138 100 59.86
00:05.8 5875 8 11 12.31 138 100 60.27
00:05.9 6031 8 12 12.05 137 100 60.56
00:06.0 6063 7 12 12.05 137 100 60.88
00:06.1 6156 7 14 11.79 135 100 60.48
00:06.3 6281 6 14 11.79 135 100 61.71
00:06.4 6406 5 15 11.54 134 100 61.6
00:06.5 6469 5 15 11.54 134 100 62.21
00:06.6 6563 6 15 11.54 133 100 63.11
00:06.7 6688 5 15 11.28 133 100 62.87
00:06.8 6781 5 15 11.28 132 100 63.74
00:06.9 6875 5 15 11.03 132 100 63.19
00:07.0 7000 5 15 11.28 130 100 65.8
00:07.1 7094 4 15 11.28 130 100 66.68
00:07.3 7156 3 16 11.03 129 99 65.78
00:07.4 7281 3 16 11.03 129 98 66.92
00:07.5 7313 6 14 11.03 128 96 67.22
00:07.6 7406 8 14 10.77 128 95 66.47
00:07.7 7406 9 14 7.95 128 14 49.06
00:07.8 7250 7 31 3.08 128 14 18.61
00:07.9 6906 0 33 2.31 129 14 13.29

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[Black_Bullet]

( Yea it appears we are going back and forth from forum to forum. Thats fine )

Still a little too much knock in there, not enough to harm the engine but just enough to rob precious power since your not getting full timing values obviously, but looks like its getting better.

If your IAT's are accurate Id say your air temps are way too high. That is likely causing some knock.
That cold air intake looks like it would do a lot for you right now.

A few other things I can add to help get your knock down

- Make sure your running non projceted spark plugs ( i.e. I run BR7ES )
- Make sure there arent any boost leaks ( thats a biggie )
- A better intercooler would help, bigger meth nozzles may help a lot too. Might be time for that.
- Try some sea foam engine cleaner, it gets out any carbon build up resulting to hot spots in cylinders.

The more you can get knock down at this point WITH keeping your current boost level and timing map, the more your power is going to go up. With this tune/ boost level a zero knock pull on that timing map would probably feel awesome.

What AFR are you at by the way?
Without going lower than 10.9ish at richest, If you are higher than that id drop it some. That could help with knock a bit, especially in the lower rpms during the boost spike.
Calming down the knock down low in the rpm range will weaken the knock up top and allow more timing up top.

Being that you have higher compression than I do and a bigger turbo holding boost a little longer Id say your doing pretty good so far but rememebr timing doesnt mean much directly from car to car, but just for your reference at WOT my timing map looks sort of like this with only 3-6 counts of knock, no timing being pulled -

3k- 12
3500- 12
4k- 10
4500- 11
5k- 12
5500- 13
6k- 16
6500- 18
7000 up- 19

The timing is a little soft down low but its more of a sacrifice to keep running 25psi on 93 octane while allowing the current timing mid range. Mid range and high rev is all that matters at a drag race anyways.
If I were to start with say 12-13 degs of timing by 4k Id knock the entire pull. Tuning is just a balanceing act between variables with a very fine line. For getting good upper rpm and peak timing, I found best results by getting the pull knock free thru the first 5 thousand rpms. Normally were I get any knock at all is right around 6k were it starts getting more aggressive but by that time Im almost at shift point anyway, and Ive never knocked bad enough that it will chase me into the next gear. Beside boost falling around 6k is also why I can ramp it up so fast at that point... You just have to know were boost spikes and falls to know what you can do with your timing at certain rpm points.

If I didnt have my pesky little boost leaks at my tb shaft seals and bov and if I had one of those monster super efficient race intercoolers I can bet id get away with another 2-3 degs of timing across the board with the same amount of boost and knock !

 

[soldave]

( Yea it appears we are going back and forth from forum to forum. Thats fine )

Still a little too much knock in there, not enough to harm the engine but just enough to rob precious power since your not getting full timing values obviously, but looks like its getting better.

If your IAT's are accurate Id say your air temps are way too high. That is likely causing some knock.
That cold air intake looks like it would do a lot for you right now.

Yeah, although the intake temps were rising with every run as they were only 3rd gear runs and then I was pulling to the side of the road and putting A/C on which heated things up a lot. When I'm doing my usual runs the air temps start at around 135F and end up around the 108F mark . Still a little warm though

A few other things I can add to help get your knock down

- Make sure your running non projceted spark plugs ( i.e. I run BR7ES )

Got BR8ES in mine which sorted out a bit of knock

- Make sure there arent any boost leaks ( thats a biggie )

Need to do that in a week or 2

- A better intercooler would help, bigger meth nozzles may help a lot too. Might be time for that.

Just upgraded the intercooler to a Treadstone one rated at 700hp

- Try some sea foam engine cleaner, it gets out any carbon build up resulting to hot spots in cylinders.

Could do that. Won't the meth/water mix also do a decent job of cleaning the engine?

The more you can get knock down at this point WITH keeping your current boost level and timing map, the more your power is going to go up. With this tune/ boost level a zero knock pull on that timing map would probably feel awesome.

What AFR are you at by the way?
Without going lower than 10.9ish at richest, If you are higher than that id drop it some. That could help with knock a bit, especially in the lower rpms during the boost spike.
Calming down the knock down low in the rpm range will weaken the knock up top and allow more timing up top.

Not sure what my AFRs were today as it was the kind of road you can't take your eyes off when I was doing my pulls, but I think I'm in the low 11s when my turbo's spooled. Need to check that out though.

Being that you have higher compression than I do and a bigger turbo holding boost a little longer Id say your doing pretty good so far but rememebr timing doesnt mean much directly from car to car, but just for your reference at WOT my timing map looks sort of like this with only 3-6 counts of knock, no timing being pulled -

3k- 12
3500- 12
4k- 10
4500- 11
5k- 12
5500- 13
6k- 16
6500- 18
7000 up- 19

Thanks for that. Nice to have a reference

 

[bastarddsm]

You might want to look into the double load range map set up. I'm not sure if its possible, but I think it would certainly help thing out.

 

[Black_Bullet]

Yea I forgot that the meth will clean the cylinders. So forget the sea foam.
And you shouldnt have any issues with the spark plugs your running.

So basically Im down to what I said about the boost leaks, AFRs, bigger meth nozzle';
and the intake air temps ( mind you my IAT's on average are about 40 degs cooler than yours...Significant to knock...? Idk )

 

[soldave]

You might want to look into the double load range map set up. I'm not sure if its possible, but I think it would certainly help thing out.

A whoody what range map?!

 

[soldave]

Last post of the day, and 2 final logs for you. One is from a 4th gear pull which came in at 400hp on the Rev/Speed meter, and the other was a launch up until midway through 4th gear. Launched at 5,500rpm with about 6psi of boost and it launched nicely with only a tiny bit of wheelspin. You can see the knock ramping in in each gear as boost spikes, but then it does subside. Cooler air temps might have helped a little with power & knock. May try taking a degree of timing out at 5000 and 6000rpm (have already taken as much as I can really at 5500rpm). Otherwise I'm going to be looking at boost leaks and meth nozzles as said before.

As for AFRs, in 4th gear I was getting AFRs of about 10.7-10.9 with a tiny spike to 11.2 at one point but I couldn't spot where it was.

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4th gear roll

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Launch results

 

[Black_Bullet]

Yea boost leaks really lower the turbos efficiency, and make the tune harder to dial in the way you want it, and it affects the overall consistency of a pull... Id say 70 percent of us have boost leaks, whether minor or large.
FWIW, Say you are leaking 2 psi worth of air, then when your spiking 26psi your turbo is really working
at the shaft speeds of 28psi to make up for the 2psi lose of pressure.
More pressure ( faster shaft speeds) equals more heat. More heat, less power.
So basically its like your tuning for a 28psi tune and thus limiting your timing severly.
At least thats my understanding of how the affects of a boost leak works.

 

[soldave]

I still haven't managed to do any 1/4 mile runs yet (mixed weather here plus the lack of a 1/4 mile straight stretch of road without a tight turn right after it or the chance of a drunken van driver pulling out without looking), but I did do a 4th gear pull on the expressway yesterday. I don't know if it's because I'm currently in the process of moving to a 75% methanol mix or what, but I hit a new power record of 412ps, spiking to 1.77 bar and holding at about 1.5bar. More pleasing was that it was at 7100rpm which means I was making power beyond the initial boost spike. And to finish it all off, that was in the middle of the day where the heat and humidity usually take a big toll on my power runs. Am also in the process of playing with the gain on my boost controller, trying to reduce the spool time as it's just a little late to kick in.

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[pneumo]

Here's a quick tip I remembered after looking at your csv data: you can find approximately where the torque peak is by looking where injector PW peaks, assuming you haven't done anything wacky with the A/F ratios. In your case it's around 5500rpm, which is where knock kicks up.

A whoody what range map?!

The double load range map mod, aka Extended Timing and Fuel Maps, is an ecu mod developed for e931 code base. It was previously hosted at hwnd.org - 1G DSM EPROM Editing but it's gone now.

Another way to extend the range of your fuel and timing maps is to reduce the maf scalar by 2/3 (or whatever number rounds out better), then make a new timing and fuel map to match the new scaling. It's a bit of work to shrink the existing rows from 16 rows to 10.6 (or whatever you've chosen) then extrapolate an extra 6 rows, but it'll keep you from running on the highest load level whenever your in boost. It's great for dealing with boost spikes since a boost spike doesn't always happen at the same rpm. Essentially the load pointer can float in the middle of the map, instead of being locked into the highest load level. All you have to know is the locations of the maf scalar, fuel and timing maps. GL!

 

[soldave]

Still not done a 1/4 mile run but managed an 1/8 mile run close to my home on a crappy road surface. Launched with 0.35bar/5psi boost (maybe a little less) and at 5,500rpm. Wheels spun a little but picked up traction very quickly. The pass ended up being 7.73s @ 154kph/95.65mph. That's 15kph more than my best previous 1/8mile time and 0.15s better than my best ever exit time. Things are looking promising for a sub 12s 1/4 mile once I eventually get around to doing some passes!

 

[Black_Bullet]

What have you done for weight reduction.. Thought about getting more speed out of lighter weight yet?

 

[soldave]

Haven't done a huge amount. Rims are a little lighter than normal meaning less deadweight (or whatever that's called), but other than upgrades which mave resulted in lighter parts being on the car, that's about it. No spare tyre and jack, of course, and all the material taken out of the trunk. Would like to keep my back seat though. I would consider replacing the front passenger seat with a light bucket seat but waiting for one to come up at a decent price. Things like the a/c and power steering I need. Only a madman would drive around Okinawa without a/c. Door panels etc are still in as I like to have a few creature comforts in the car - it is a daily driver after all.

And for the record, I looked at my logs after the runs last night. Have taken 1* of timing out at 4,500rpm, 5,000rpm, and 6,500rpm and taken the boost controller down 1% to try and get rid of this knock once and for all.

 

[Black_Bullet]

Bigger meth nozzles and leave your timing and boost and be done with knock once and for all. : )

Also have you scraped out all the sound deadner, padding on firewall, exhaust heatshields, gas tank shields, etc... That kind of stuff you cant see and that stuff adds up quickly.
Thats if your Evo has any of that like dsm.

 

[soldave]

Am already up to an M10 nozzle with 75% meth. You think an M12 is the way to go?

Not sure if there are gas tank shields. When you say firewall padding, I assume you're meaning on the interior side? As for sound deadening stuff, are you meaning the stuff on the inside of the dooor panels that's really sticky stuff?

 

[Black_Bullet]

Am already up to an M10 nozzle with 75% meth. You think an M12 is the way to go?

Not sure if there are gas tank shields. When you say firewall padding, I assume you're meaning on the interior side? As for sound deadening stuff, are you meaning the stuff on the inside of the dooor panels that's really sticky stuff?

Padding on inside and outside of firewall, sound deadner under carpets and on fire wall, theres thick padding under the carpet on dsms that can be pulled. Theres normally a shield over and around the stock gas tank on most cars... Stuff like that.

 

[soldave]

Padding on inside and outside of firewall, sound deadner under carpets and on fire wall, theres thick padding under the carpet on dsms that can be pulled. Theres normally a shield over and around the stock gas tank on most cars... Stuff like that.

Hmmm... will have a look under the carpets and see what I can find. Think it might just be floorpan but will check this weekend. Any weight I can get rid of will help.

Laxatives before any drag racing event will be taken too!

 

[soldave]

Slight update on tuning the car. Have come across a new bit of code for my ECU which may help with my launches. I currently have launch control set at 5,500pm which means that as soon as I'm moving it shifts up to my regular 7,700rpm limit. Now with this new bit of code I can set the launch control rev limit to stay in place until I hit a certain speed, which could help control some of the initial spin. I put the launch control speed limiter into play this evening and had a little play around. I only managed to do about 6 short runs but it gave me a feel for the system.

I set it up initially at 20kmh/12mph and did a couple of runs. Wasn't sure it actually did anything and my 200m (1/8 mile) times were a little over my personal best of 7.72s. Changed it up to 25kmh/15mph and did 2 more runs. I think it had a slight effect and even when I launched with 0.7bar/10psi of boost I only had limited wheelspin. Now I have to admit I didn't feel it hitting that 5500rpm limiter so I'm not so sure if it had an actual effect. I did manage to get a quicker 200m time by 0.01s with a slightly quicker 100m time although a marginally slower exit speed.

More testing is definitely needed before I can work out for sure what if any effect it was having. Let me know what you think about the theory of it.

 

[pneumo]

I haven't studied traction control, so I can't help much. I would like to offer this bit of info; according to fbody.org assuming you have the same gear ratios and tire size as the US DSM your car will reach 27mph at 5500 rpm in first gear. Best traction happens with a little wheelspin, not too much. Using the launch revlimiter too aggresively will reduce power, not aggresively enough will give you too much wheelspin. In the end you're already doing the right thing by trying different settings to see what works best. You may have to alter your launch technique to get the most out of the new code. There's a chance that you can be more aggresive with the clutch and throttle and let the ECU handle traction control duties.