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I can already deadhook 1st. And you don't want a torque converter above peak torque. These motors have such low peak torque. I've stalled mine to about 2k, but can't leave in boost....not 1-2 psi. I mean real boost. That would likely drop at least .25 off the 60ft.
Peak torque is like 3500-4500rpm depending on tune.
Isn’t our stall around 2400? A 3400 stall would do wonders.

When you say stalled to 2k but can’t leave in boost what do you mean? Wheel spin and can’t hook? Or Hooks and then bogs? Or it doesn’t build any boost? can you flash stall with the brake, hold brake floor it lift brake right as it hits 2k might build more boost off the line.
 

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It doesn't build boost. The aftermarket tunes have a launch mode that lets them leave like a 2 step.
I know how LC works on manuals and DCT but how would it work with a converter. Set limiter in 1st while braking to stall speed so you can just keep it floored? How would this build more boost as apposed to just modulating throttle to keep it at stall speed manually yourself? LC seems like more of a consistent convenience as apposed to an actual improvement. And seems in either case a high stall 3400ish converter would do wonders.
 

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Gotta love forum theories this is why I stoped looking here.
here’s one of the test hits where I was trying to get the transmission to shift early and hit throttle cut in first losing a lot of momentum. Car still trapped 108mph in the 1/8th on a flat slope. If you wanna compare the other car trapped 105. (Dragy leaderboard adds 2 mph to the 1/8th after you post the timeslip for some reason)
3 mph in the 1/8th that’s a biiig difference in power View attachment 97508
Your times are super impressive. Your build gives some of us something to look towards. 👍🏼
 

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I know how LC works on manuals and DCT but how would it work with a converter. Set limiter in 1st while braking to stall speed so you can just keep it floored? How would this build more boost as apposed to just modulating throttle to keep it at stall speed manually yourself? LC seems like more of a consistent convenience as apposed to an actual improvement. And seems in either case a high stall 3400ish converter would do wonders.
If you're familiar with a 2 step rev limiter, it doesn't just limit rpm, it usually intermittently cuts spark to each cylinder. This allows unburnt fuel into the hotside of the turbo which spools the turbo. You can build 5,10,20, 30 psi depending on the platform and the setup. It also can advance or retard timing to assist in building the boost. Usually it's retarded for a manual and advanced for an auto. Think of this as a lean spool mode that the VR30 uses but you're not moving and have an intermittent spark cut. If you had this feature you wouldn't need a torque converter at all to cut some wicked times. If I had more free time is start looking over the schematic to see if I could build a momentary spark cut off the ignition harness....just too busy unfortunately. It would really put us WMI JB4 users on par with tuned cars.
 

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That is weird shows you at 111 on dragy.

3mph is a lot. Same difference between your 1st run and 2nd run despite identical ET are also 3 mph difference in trap which is odd.
Especially since the slower Trap run has slightly higher MPH in the 1/8th but then you picked up 3mph on the back end but with no difference in ET on the 1/4, only change is road slope.
mid you lookat both passes the real reason that makes 3mph difference in the trap speed is that I lost power during 1st one at top of 4th and had to shift into5th. You can hear it in the video as well, that is not because of the slope.
 

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I can already deadhook 1st. And you don't want a torque converter above peak torque. These motors have such low peak torque. I've stalled mine to about 2k, but can't leave in boost....not 1-2 psi. I mean real boost. That would likely drop at least .25 off the 60ft.
I used to leave at 15 psi consistently when I was on stock turbos. My RWD friends tuned by ams do 10 psi with a really good lc that one ran 10.90 on the street with stock diff
 

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I used to leave at 15 psi consistently when I was on stock turbos. My RWD friends tuned by ams do 10 psi with a really good lc that one ran 10.90 on the street with stock diff
On another platform I couldn't get better than mid 12s in a stick shift turbo car. Put a tire on it and went high 11s. Put a 2 step on it and went mid to high 10s 🤣 2 steps/launch modes rule! I have no doubt if I could leave on 10 pounds my JB4 car would run a bottom 11.
 

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With the power some of the JB4 cars put down it really has to be the launch that is holding it back. I can't even spin the damn tires on a cold road with the factory runflats in my AWD. On the stingers they found a way to let them launch harder buy putting a switch on one of the brake wires to fool the factory nannies. Before doing this even with factory launch control they have a hard time breaking 1.9s .
On another platform I couldn't get better than mid 12s in a stick shift turbo car. Put a tire on it and went high 11s. Put a 2 step on it and went mid to high 10s 🤣 2 steps/launch modes rule! I have no doubt if I could leave on 10 pounds my JB4 car would run a bottom 11.
 

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With the power some of the JB4 cars put down it really has to be the launch that is holding it back. I can't even spin the damn tires on a cold road with the factory runflats in my AWD. On the stingers they found a way to let them launch harder buy putting a switch on one of the brake wires to fool the factory nannies. Before doing this even with factory launch control they have a hard time breaking 1.9s .
That's what I've been bugging Terry about. We need a form of launch mode or a 2 step. I can deadhook 1st with my LSD upgrade on my drag radials, but can only leave in may 1-2 psi of boost.
 

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2019 Q50 Luxe RWD
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Carolina >>>>>>

We fast fast here

Minus me. I'm regular.
 
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Discussion Starter · #34 ·

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Did I see something on the Dragy that you cut a 4.0 0-60?
Yeah my best is 4.08 when I was still getting dialed in this past summer. That was the only time I had a sub 2 second 60ft. Ran 12.10 on that run in 2300+ DA

I've gone 12.04 since then but both the 60ft and 0-60 were worse. I don't think these guys are gonna let me borrow the drag pack so my 11 second goal will be unachieved until the next car. Unlikely to keep trying on these tires
 

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Yeah my best is 4.08 when I was still getting dialed in this past summer. That was the only time I had a sub 2 second 60ft. Ran 12.10 on that run in 2300+ DA

I've gone 12.04 since then but both the 60ft and 0-60 were worse. I don't think these guys are gonna let me borrow the drag pack so my 11 second goal will be unachieved until the next car. Unlikely to keep trying on these tires
Congrats on the 0-60! The Dragy app showed you were JB4 so I was scratching my head but it makes sense now. :ROFLMAO:
 

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Congrats on the 0-60! The Dragy app showed you were JB4 so I was scratching my head but it makes sense now. :ROFLMAO:
Yea it captures the moment in time and I hadn't updated it at that point, I never surpassed that 4.46 on JB4, not even close hah
 
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If you're familiar with a 2 step rev limiter, it doesn't just limit rpm, it usually intermittently cuts spark to each cylinder. This allows unburnt fuel into the hotside of the turbo which spools the turbo. You can build 5,10,20, 30 psi depending on the platform and the setup. It also can advance or retard timing to assist in building the boost. Usually it's retarded for a manual and advanced for an auto. Think of this as a lean spool mode that the VR30 uses but you're not moving and have an intermittent spark cut. If you had this feature you wouldn't need a torque converter at all to cut some wicked times. If I had more free time is start looking over the schematic to see if I could build a momentary spark cut off the ignition harness....just too busy unfortunately. It would really put us WMI JB4 users on par with tuned cars.
Any luck with this? I'm admittedly ignorant on how a 2 step rev limiter works other than what you describe above. Is this how EcuTek tune effectively operates to reduce turbo lag/spool-up time on launch (if not, how?)? I'm AWD and basically looking for boost/power on demand without brake boosting or messing around with a complicated launch control procedure. Right now boost doesn't hit target until 3,500-3,800RPM or so (no brake boost). Current mods are just JB4 w/ FW+EWG and HKS LDPs, but have FI CBE on order and have inquiries into dealerships/vendors on AMS/Infiniti HX, expansion tank, intakes. From there make a decision on EcuTek or stick w/ JB4, possibly add WMI to JB4 (thanks to all the pioneering work of Ddnspider on the WMI, I MAY be brave enough to attempt!). Thanks everyone.
 

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I would suggest that any JB4 users who want a launch mode or 2 step mode go on n54tech to the q50/60 thread and bombard Terry/Ando requesting it. So far he's ignored all of my probably dozen requests.
 

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I would suggest that any JB4 users who want a launch mode or 2 step mode go on n54tech to the q50/60 thread and bombard Terry/Ando requesting it. So far he's ignored all of my probably dozen requests.
Thanks. Just posted on n54 quoting you. Feel free to add on. Seems like something BMS could address, especially with EWGs? If not I may take the plunge to EcuTek.
 
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