Well today I made the discovery of my lifetime with this damn pos. I was watching my last few drag movies of my car trying to figure out my problems. I was watching the 12.0 run that i did last time out and the launch seemed great but between shifts it looked like the car just died. It also took a little while for the turbo to respool (Especially in the 3rd to 4th shift). I could not figure out why this was happening... I knew I was shifting the car plenty fast and was trying to solve the mystery... I just figured I still suck at driving. Finally today I learned that this is not the case at all.

I did some accurate datalogging (Zeitronix roughly around 60 frames/sec) and tried to deduce the problem. I learned that between every gear the RPMs would fluctuate from 4900 to 6k (Looks like a horrid rev limiter or something). I was trying to figure out if it is because I was banging out the clutch too fast and I should be slipping it. Anyways... i figured I would try to shift the old school way (Without the launch control on) and see what it looked like then. My dumb@ss forgot that I need to lift the gas up between shifts so I just did it like I always do and left the gas floored. It bounced off the rev limiter once and just LAUNCHED when it hit the next gear... it felt like I launched the car in 1st from a dead stop except i was already moving around 40mph. I then decided to do this again with a little lower rev limiter just to be safe and log it. The results were ASTOUNDING.

I learned that before I turned off the launch control the RPMs would dip at the lowest about 4900 RPMs from a 7900 RPM shift from 1st to second. Seemed a little large a gap to me but I never figured anything was wrong. Now, shifting from 7.4k from 1st to second it only drops to 5.2k which means I was actually slowing the car down between shifts the old way. Not just taking a long time but physically slowing it down.. obviously alot considering a shift from 7.2 results in a 5.2 land compared to an even higher shift 7.9 landing to 4.9... I was slowling the hell out of the car and despooling my big @ss turbo.

I then figured I would calulate the sheer difference in time from shifting alone (Not even to mention the difference in total speed from spool) but the shifting by itself on average was 0.224 seconds faster this way AND kept the turbo spooled decently. The log I compared my new log to was from a 12.2 second pass. Mathematically speaking... this would mean that my 12.2 if I would have shifted it this way would result in that time dropping to a 11.54... THAT time would have actually made sense trapping at 118.9

I am SO excited about this discovery I can not hold myself in. I tried to go to the track today to run it again but it rained out... next time i can make it will be on Friday. I hope that this time I will be hitting 11.5's and 11.6's all day. Hopefully hit an 11.49. Once I finally make sure that I am driving the car so the ET's match the trap (Which I fully believe this will do now!) I will FINALLY turn up the boost to where it should be at the track and shoot for a 10.99 at 30psi or so.

Im just so damnd glad... after EVERYONE saying it is my shifting making the runs slow but me never figuring out how to shift it better... I learned it is not actually me being retarded but my car just wouldnt let it happen. It also makes perfect sense to me now as well.

Thanks everyone for helping me to actually look at my shifting more closely! I think I have finally made the stupid car so it will run what it should. The only crappy thing is I now have no launch control which will make it harder for me to launch it.
I might try to make a race track only map which has the low load point at around 1-5k have -5 degrees of timing which should help it spool a TON while I floor it at the line before the launch. I tried it out a little bit and bot it to build 20psi stuttering. Im figuring I can get 5-7psi without stuttering with timing only. Ill keep yall informed!

 

Cool, hope the new shifting works. Sounds like it will drop your time substantially.

 

If anyone has the Zeitronix software or wanted to download it I will post up the logs. It is really funny when you look at the two and how different they actually are.

 

definatly post an update on here, as I think there is good info to be had.

I also seem to have an issue with my AEM EMS system using one cluth switch for both launch rpm control and wot shift cut.

If I use the bottom switch to launch, you effectively lose the wot shifting limiter since it's only switched at the very bottom of the clutch pedal travel, and frankly, I don't think I even push the clutch down that far during a shift to even hit it.

if I use the top switch (currently doing this), the launch control has a tiny touch of lag..sometimes the engine will sit on the second launch rev limit for a bit while im trying to slip the clutch out. that's not a big deal at all. But I feel it does slow down the car between shifts in that the clutch engages a bit and can be accelerating the car while the clutch pedal is on the way up. I always wondered how much et was lost becuase of this.

unfortunatly, the ems does not have 2 seperate secondary rev limits, that would be ideal.

first for launching, second for shifting. you can set the ideal shifting limit to the rpm the engine will be at when the next gear is engaged. (within a couple hundred rpm, as each gear ratio to next is not even).

oh well..some comprimise as always.

 

I need to run to work right now but tonight I will post up my findings from the Zeitronix so you can compare the two runs. It is a staggering difference with the Utec. I now shift without the 2-step at all... just bounce it off the rev limiter and the car just SHOOTS forward. I think the problem was it was cutting power even with the clutch partially engaged and kept cutting power for a millisecond after it was engaged. Like I said before, you can see in the logs that it was actually slowing the car down physically by the RPMs in the next gear being much lower than they should have been so not only was it losing boost and bogging but actually slowing it down as well. I will also post up a log from shifting more like a normal human being. I finally got the boost sensor so it is funny on how much boost you lose if you let off the gas between shifts. I will try to make another log shifting the same way I did at the track but with the boost sensor installed to see how much boost i was losing at the track.

Doing it this new way I only drop to about 18-19psi where as lifting off the gas drops it to about 1 psi. Ill post all these logs and try to get another one tonight with the launch control.. I suspect that it will kill the boost as well.

I am assuming you have the Zeitronix software also... you will need it to look at the logs. You could get it from Zeitronix.com if you dont have it already. Ill post em up tonight for ya to look at.

 

Thats what I was getting at with only lifting just enought to keep off the limiter betweeen shifts. Glad you got it figured out.

 

Ok well here are some logs for ya... One is the rough difference from shifting while lifting the gas completely (Not slamming gears as fast as I possibly could but pretty quick) compared to shifting without lifting the gas with no launch control turn on (Or any other type of stuttering device aside from the primary rev limiter). It also shows my boost between shifts and how long respool takes conventially shifting (Amplified for most because I have the GT35r.. obviously the stocker would respool MUCH faster but you can still see the difference).

Another log is showing the runs that I made at the track which resulted in a 12.2. You could compare that log with the new way of shifting. You can also calculate the time difference of shifting by measuring how many frames it took me to shift both ways. The run at the track was no lifting the gas but it was using the launch control/flat ****ing method.

Just for the info as well.. the Utec uses the top clutch switch (If you ever look at where it is you will know why it is the TOP switch... your clutch pedal needs to literrally hit the stop at the highest point. The top switch is actually where the clutch pedal sits so it couldnt get any higher. I think that if you could use the bottom clutch switch it may perform much better but the Utec doesnt give that ability right now.

I will try to run outside real quick and turn on the launch control and do some flat shifting with it turned on while I can log the boost as well. This should let you know how much boost is lost when using this method. My guess is it will be in between the not-give-a-**** type shift (Bouncing off the rev limiter) and the 'normal' style shifting (Lifting the gas between shifts).

I will be at the track tomorrow so I guess this will put all my theories to rest and finally lay out whats real. Im honestly guessing a HUGE difference in track times and I will be shooting for an 11.49 but would be plenty happy with an 11.6 or so. This is also at 25.5psi of boost so it isnt much at all for this turbo. I will also try to wire up a switch/button so I can still use my launch control for the launch but switch it off after I launch it... this would help me get consistant launches. I also remembered that the 60' time is not only the launch but also the shift from 1st to second so we will see if that changes tomorrow (If I can get any good launches ). Im hoping I can drop it down into the 1.6's or so. Anyways heres the logs (You need the Zeitronix software to read em)...

Ill go get some of the other logs right now and post em up in a little bit. This will show the boost loss that I had during the track run (I didnt have the boost sensor at the track so you cant see boost in the track run so I am curious to see that as well)

 

Well I figured not lifting the gas would be the best way I didnt realize that by using the launch control it was ultimately killing me. I figured I would do it like I assumed everyone else did with some sort of EMS capable of flat shifting... turns out it definately doesnt work with the Utec

 

Well yet another problem with the damned problem I think I can still get my mid 11 passes later today but I just now figured out I can not run more than 25.5psi My wastegate spring apparently will not allow it. So... at 25.5psi we will see what i can run My ghetto VDO Guage still reads kinda strange but i turned the boost all the way up and it doesnt change anything at all. Oh well... I guess Ill just shoot for an 11.49.. just enough to get tossed out of the track

 

How did you do?

 

11.5 @ 123

I was quite amazed at the gain in MPH. I got a few new posts floating around now about the runs

And this is what I have noticed about the shift-no-lift (Good info for you DS Motorsports). If I raise the shift RPM stutter (Which happens to be the same as my launch option as it seems your stuck in as well) it works out fine....I have figured out that as long as you set it at about the same RPM as your shift point it works fine. The problem is, at least with the utec, if you set it alot lower the Utec cuts power for too long slowing the car down between shifts. If I get some time I will rewire the clutch switch so it uses the bottom switch instead and see if that helps. The boost itself doesnt actually go to low.. for me it stays over 14psi so the boost is ok, it just kills the power too long. I really think at the lowest switch it may work ok. Ill test it out if I get some time and let ya know. Right now I am not lifting the gas and just bouncing it off the primary rev limiter. Its a PINA though because I have a switch that enables the launch control to launch it consistnatly but I need to switch the button off right when I actually launch it. I just have a switch that I hold in my right hand while holding the shift knob and right when I launch it I switch the switch. Its kinda a b1tch but it seems to be working ok. Half of my launches I wait a little too long to switch the switch off but it is still close enough that it doesnt seem to matter much.

 

That run was also with a 1.76 sixty foot time at 25.5 psi running 12:1 AF/R with a 70-75 degree night with alot of humidity. The car was running quite well and no bad problems the whole night (Aside from one poor guy that crashed his 8 second car halfway down the track and me dropping my wierd clutch switch cut-off switch at the launch so I couldnt run once) but other than those it was a good night. I will be going to GLD alot more now. Night racing is SOOOO much nicer... cool outside. Less people, car seems to run smoother, etc...

 

I only need to lower my 60' time (Which i think is something to do with my launch) and I should be in the low 11's at the same boost. I doubt i will run the car at this low boost again though. I plan to raise it to 30 psi and shoot for the 10's next run. I think if I raise the launch RPM to 6.5 or so it will help alot. I need to slip the clutch ALOT to get it to start moving... after the first 10 feet or so the tires start spinning badly (My steering wheel is almost sideways to keep it going straight and smoke actually pours out of the front wheel well they spin so bad). The other problem that i cant figure out is why my front tires spin so badly but the rear tires BARELY spin. Anyways... if you know help me out! Otherwise I guess it is all trial and error.

 

Nice! One more run and you will need a cage!!I am glad you have your issues worked out, and I think you will run a high ten soon!!

What tires are you running and @ what psi? May be lower the psi buy3 and try that.

It may just be you are not hooking up, and not the launch method try different tires.

Congrats on your time!!

 

Im more than confident that if I had more time to run that day I would have hit an 11.49 or faster. I really think raising the launch RPM will help it out but even without changing anything I went from a high 11.6 to a mid 11.5 in three runs without changing anything. I would only assume that given two more runs down the track I would be there. Im not too interested in the 11.49 thing though. More concentrated on the 10.99 now

The tires are Sumitomo sumthing or other that has a very low treadwear rating so they should be sticky enough. Tire pressure was around 25psi or so all around. Even on these tires I know I could hit 1.6's or even high 1.5's so I am determined to do it

I also have plans to get a roll cage and all the other BS needed to run 'legally' at 10.0-10.99 in a month or so and I will probably only run the car two times before then. It wont take me more than 3 runs a day two times ti ensure i hit the 10.99 so I should be ok. I hear through the grapevine I can run it usually 3 times breaking the rules before I get tossed so I should be ok. Im still trying to figure out exactly what i need to 'legally' run 10's.... so far it seems I need the Roll bar (Or cage), a fire extinguisher, a fire jacket, a window net (Maybe??), and a flywheel scatter shield (Which I already have installed). If anyone has any more items I need let me know I will probably just ask the guy that will install the cage what i need for sure and just get it all done at once when I do. Ill have to remove the bumper metal to account for the extra wieght