KTuner Extended Testing And Tune Results

[Florence_NC]

That doesn't sound all that loud. But you can't really tell form a cell phone microphone.

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[Florence_NC]

On another note, I have been experimenting with how to best do a roll-on in a CTR. Even if you can get the engine at 5000RPM or better, there is so much turbo lag that it gives up too much from the initial hit.There is also some significant lag every time you change gears causing some loss in performance. It is especially bad during the 1-2 shift where the less-than-stellar transmission issues keep one from really speed-shifting to keep everything spooled up.

So I tried to see if I could mitigate the roll-on issue by dragging the brakes while giving it some throttle to get it to build a bit of boost before the all-out WOT hit. But it won't work. As soon as you touch the brake pedal, something in the system completely shuts down all power. It feels and acts like the throttle blades close no matter what the throttle pedal position if the brakes are activated. Watching the boost shows a drop in MAP to something well into the vacuum range, also indicating closed throttle blades. Is there any understanding of this system, and any way in the KTuner to defeat it? Or any way in general to get rid of some of the lag in the turbo within the tuning?

 

[fiend busa]

On another note, I have been experimenting with how to best do a roll-on in a CTR. Even if you can get the engine at 5000RPM or better, there is so much turbo lag that it gives up too much from the initial hit.There is also some significant lag every time you change gears causing some loss in performance. It is especially bad during the 1-2 shift where the less-than-stellar transmission issues keep one from really speed-shifting to keep everything spooled up.

So I tried to see if I could mitigate the roll-on issue by dragging the brakes while giving it some throttle to get it to build a bit of boost before the all-out WOT hit. But it won't work. As soon as you touch the brake pedal, something in the system completely shuts down all power. It feels and acts like the throttle blades close no matter what the throttle pedal position if the brakes are activated. Watching the boost shows a drop in MAP to something well into the vacuum range, also indicating closed throttle blades. Is there any understanding of this system, and any way in the KTuner to defeat it? Or any way in general to get rid of some of the lag in the turbo within the tuning?

That brake and throttle is a safety thing. Think it has to do with that whole "unattended acceleration" that happened with Toyota (?) way back

Brake while always take priority over throttle if both are stepped on.

 

[Florence_NC]

That brake and throttle is a safety thing. Think it has to do with that whole "unattended acceleration" that happened with Toyota (?) way back

Brake while always take priority over throttle if both are stepped on.

That is what I figured as well. There has to be a way to defeat it. How can you trail brake when road racing with this feature activated? And "Fully Off" doesn't stop it, I tried.

 

[boosted180sx]

That is what I figured as well. There has to be a way to defeat it. How can you trail brake when road racing with this feature activated? And "Fully Off" doesn't stop it, I tried.

be on the throttle first then press the brakes. not brake then throttle.

 

[Florence_NC]

be on the throttle first then press the brakes. not brake then throttle.

From what I can tell, it doesn't make any difference the order. Once you hit the brakes, the throttle closes no matter what.

 

[boosted180sx]

From what I can tell, it doesn't make any difference the order. Once you hit the brakes, the throttle closes no matter what.

oh i remembered it wrong.
seems like this is the way. This was from a while back on one of the fb groups.

 

[redline]

On another note, I have been experimenting with how to best do a roll-on in a CTR. Even if you can get the engine at 5000RPM or better, there is so much turbo lag that it gives up too much from the initial hit.There is also some significant lag every time you change gears causing some loss in performance. It is especially bad during the 1-2 shift where the less-than-stellar transmission issues keep one from really speed-shifting to keep everything spooled up.

So I tried to see if I could mitigate the roll-on issue by dragging the brakes while giving it some throttle to get it to build a bit of boost before the all-out WOT hit. But it won't work. As soon as you touch the brake pedal, something in the system completely shuts down all power. It feels and acts like the throttle blades close no matter what the throttle pedal position if the brakes are activated. Watching the boost shows a drop in MAP to something well into the vacuum range, also indicating closed throttle blades. Is there any understanding of this system, and any way in the KTuner to defeat it? Or any way in general to get rid of some of the lag in the turbo within the tuning?

I freaking hated how my ctr shifted in all the gears, like hitting a brick wall no mater how fast I shifted. I removed the clutch delay valve and I can rip gears as fast as I want now. With the the clutch delay valve the faster I would try and shift the worse it would be.

 

[Florence_NC]

oh i remembered it wrong.
seems like this is the way. This was from a while back on one of the fb groups.

I went out and messed around with this again, and they are correct. You have to be completely off the brake, then roll completely off the throttle, and I do mean 100% completely off. Then you can apply enough brake to trigger the brake light/safety switches first, then start to feed throttle and brake into it. It will definitely build boost that way, I was seeing about 20lbs in 3rd gear at 5000ish RPM while holding a steady speed.

This is not the easiest way to go about this, but it does work. Still doesn't solve the issue of trying to trail brake in corners while road racing. Is there ni way in any of the tune software to eliminate this?

 

[Florence_NC]

I freaking hated how my ctr shifted in all the gears, like hitting a brick wall no mater how fast I shifted. I removed the clutch delay valve and I can rip gears as fast as I want now. With the the clutch delay valve the faster I would try and shift the worse it would be.

Same with me. I have been racing manuals for 30 years, and I can just plain outshift my car in stock configuration. Especially 1-2 shift, I have to really be deliberate and slow down my shift to get it to not grind into 2nd. And when you have to slow down the shift, even by a fraction of a second, it falls out of full boost and has lag at the beginning of every gear. I am guessing some of that lag is in the tune and could potentially be eliminated. But if the turbo loses spool during a slow shift, no tune can fix that.

I need to do the delay valve mod and adjust the pedal travel to see if that helps. Will probably do the Acuity shifter eventually as well.

 

[Streetthrowback]

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[d15b7]

hey guys. I road race with NASA and SCCA and VRG (out on the east coast). I've held road racing licenses since 1999 and also instruct for the Porsche Club, BMW CCA, NASA, Chin, and others. OK - so 'trail braking' is this: as you approach a corner, instead of doing all your braking in a straight line and then turning in, you brake late and as you turn in you are still braking almost up to (and sometimes right up to the apex). when trail braking you are NOT touching the throttle, just modulating the brake pedal and generally trailing off the brakes as you turn in and approach the apex. at that time you transition to throttle gradually and feed in more and more til (if you can depending on engine output and traction) you are hopefully at full throttle at the track out point. so, with trail braking, there would be no issue with the engine dying because you are on both the throttle and brake (because you aren't ever on them both at the same time trail braking).

what I think you are thinking about is called 'left foot braking'; that is when you are using one foot on the brake pedal and one foot on the throttle and blending the two in as you are approaching a corner or transition. in the old days (think Porsche 930 turbo or Lotus Turbo Esprit or any turbo car of the 70s/80s ) this was a technique that you used due to the incredibly bad turbo lag that existed with those primitive turbo designs and also the electronics. I used to own a 1985 Lotus Turbo Esprit, and let me tell you, it had significant turbo lag. our CTRs have practically NO lag in a road course situation. like, none. I wouldn't bother left foot braking it; there isn't any need as long as you are in the correct gear on track (as you should be always) and are on line and feeding in throttle right after braking and turning in (trail braking in the CTR in +R mode, with traction control off, for certain corners seems to work well with our cars). OK, lecture mode off LOL!

EDIT: my CTR is one of the slowest cars that I own but is one of the most pleasurable street cars I've ever owned. I have several track racecars, and the fastest one by far is a 95 EG Civic that is stripped and caged and full race with a K24/20 Frankenstein and BW EFR7163 turbo (about 550 whp) weighing 2400 with driver. now THAT car is fastttttt! but it would be horrible for anything but a racetrack (800 lb/in springs up front and 1200 lb/in rear). the CTR is truly a great daily driver plus it is pretty fairly good on track too.

 

[idragmazda]

hey guys. I road race with NASA and SCCA and VRG (out on the east coast). I've held road racing licenses since 1999 and also instruct for the Porsche Club, BMW CCA, NASA, Chin, and others. OK - so 'trail braking' is this: as you approach a corner, instead of doing all your braking in a straight line and then turning in, you brake late and as you turn in you are still braking almost up to (and sometimes right up to the apex). when trail braking you are NOT touching the throttle, just modulating the brake pedal and generally trailing off the brakes as you turn in and approach the apex. at that time you transition to throttle gradually and feed in more and more til (if you can depending on engine output and traction) you are hopefully at full throttle at the track out point. so, with trail braking, there would be no issue with the engine dying because you are on both the throttle and brake (because you aren't ever on them both at the same time trail braking).

what I think you are thinking about is called 'left foot braking'; that is when you are using one foot on the brake pedal and one foot on the throttle and blending the two in as you are approaching a corner or transition. in the old days (think Porsche 930 turbo or Lotus Turbo Esprit or any turbo car of the 70s/80s ) this was a technique that you used due to the incredibly bad turbo lag that existed with those primitive turbo designs and also the electronics. I used to own a 1985 Lotus Turbo Esprit, and let me tell you, it had significant turbo lag. our CTRs have practically NO lag in a road course situation. like, none. I wouldn't bother left foot braking it; there isn't any need as long as you are in the correct gear on track (as you should be always) and are on line and feeding in throttle right after braking and turning in (trail braking in the CTR in +R mode, with traction control off, for certain corners seems to work well with our cars). OK, lecture mode off LOL!

EDIT: my CTR is one of the slowest cars that I own but is one of the most pleasurable street cars I've ever owned. I have several track racecars, and the fastest one by far is a 95 EG Civic that is stripped and caged and full race with a K24/20 Frankenstein and BW EFR7163 turbo (about 550 whp) weighing 2400 with driver. now THAT car is fastttttt! but it would be horrible for anything but a racetrack (800 lb/in springs up front and 1200 lb/in rear). the CTR is truly a great daily driver plus it is pretty fairly good on track too.

Awesome write up and easy to understand. Thanks dude.

With VSA off at the track, what happens vs with it on? I just went to an hpde and did a newbie course and left everything on and just used R mode (since newbie). There were a few times I pushed it kind of hard and the instructor also knew it but I think it was the car that saved me / never let it get out of hand - is that it? Thanks!

 

[d15b7]

you're welcome!

when I'm Instructing a novice, I typically recommend that we leave the VSA on so that if he/she makes a big error, the car has a chance of saving us and keeping scratches off it lol! that being said, our CTRs are very 'friendly' cars and are quite easy to drive with the VSA turned off (say as compared to a GT350 or a C7 Z06 or a ZL1 Camaro). I've driven all those and had them for students and with everything turned off on those high hp RWD cars it's easy for a novice to get in over his head and spin/lose it coming out of a corner and damage the car. with those types of cars I STRONGLY recommend leaving the VSA at least on on the 'track' oriented settings. for you I'd say leave the VSA on til you are driving decent laps that are on-line and without feeling the VSA 'kicking in' to make changes to save you. then at that point you may try turning the VSA off if you like.

I drive on track with it off, as I am quite experienced, plus none of my other cars have it (heck none of my other track cars even have power steering or even ABS, much less VSA lol!)

 

[KTuner]

Just wanted to share some updates, been very busy over here and haven't posted updates in a bit.

We have fan control coming to the next update.
We invested in upgraded hardware a little while back and are no longer opening ECUs in order to unlock them. This was big in terms of those worried about the ECU looking like it was modified in any way.

Hope everyone is enjoying KTuner!

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