DRAGRCR RED EYES

[AMRCN HP]

Stumbled across this thread... had my Redeye out to the track for the first time Friday night. Experienced exactly the same on the 1-2 shift. Car is bone stock with a drag pack and diff brace and me at 230lbs. Only 550 miles on the odometer at the time.

I made 4 passes. First pass was 1.48 60’ 10.47@132.45 with DA 1470’. Hot lapped a second pass for best of night with 1.47 60’ 10.44@132.66. Thought my last pass would be my best but was 1.46 60’ 10.45@133.15 with DA 1000’. Car nosed over really hard on the 1-2 last pass, just like your video.

I was logging using HPTuners and a channel file from Curt but a generic layout file so couldn’t see a lot of parameters. But what I did see was the car really shortshifted the 1-2 on the last pass - it shifted at 5500rpm. On my fastest pass it completed the 1-2 shift just under 6100rpm.

This was my first time out with a stock tune car in a long time so I chalked it up to over-protective torque management. The car felt really strong on that last pass, so maybe it forced an earlier shift?

Don’t know if this helps, but thought I’d share...

Paul...

 

[DRAGRCR]

X

 

[Dutchman]

I have a '19 Redeye and have noticed the same hiccup between shifts on the street with the stock tires during wide open runs. Not a great feeling when your pulling onto a busy highway. Dare I say a safety concern?

@DRAGRCR Maybe it's time to start a survey of all Redeye owners. To gain visibility of what percentage of owners are experiencing this hiccup issue between shifts.

 

[AMRCN HP]

What were the 1/8th ET and speeds on your runs? I was thinking this hiccup hurts me in the 1/8th but maybe I get some back in the second half. I have not run the 1/4 yet and I have same mileage as you, something like 570 miles now.

See below...

Pass 1 - 6.69@104.90
Pass 2 - 6.67@105.06 (best)
Last - 6.69@105.16

 

[DRAGRCR]

X

 

[DFW_Redeye]

Quick question for Ron - are you running a differential brace?

 

[Speedy!]

@AMRCN HP you wanna share your log with me and I can see if I can tell what it was doing? If the right PIDs were logged it'd be pretty obvious?

For you guys having this problem, what rear gear does your car have? 2.62 or 3.09?

The only time my car ever acted like the video Ron posted, I hit the rev limiter but torque mgmt would do it too. Rev limiter is easy enough to solve and it shouldn't be hitting it bone stock. Torque mgmt manipulation takes a little more thought as it is there to protect the car. Taking out some to fix an issue like presented is one thing, but take out too much and you're over stressing the trans.

Ron's video shows his 2018 Demon performing perfectly and it had 3.09 gears. His RE with 3.09s is falling over. I've got a 2019 RE calibration and a 2018 Demon calibration on my laptop, I'll look later today to see if I can see any differences in trans settings, torque mgmt, etc.

 

[Speedy!]

Took a quick look at the tunes between a 2019 RE and 2018 Demon. The tune is the Demon crate tune but I think the trans settings are the same in non crate and crate. The non crate tune I have didn't include the TCM unfortunately.

There are probably 100 differences so I focused on areas I thought would impact shifts. The Demon tune has firmer shifts for sure. The big difference I found was a setting called "Max Torque Limit Slip". On the RE it was 339 ft/lbs. On the Demon 959 ft/lbs. I bet that's the difference.

The other table I looked at was "trans torque intervention 1-2" and they were the same at WOT and only minor difference in a small spot at lower torque input. Nothing that would be noticeable.

The minimum spark torque reduction tables were identical, so the timing pulled is the same between the two.

I'm betting it's that max torque limit setting.

 

[DRAGRCR]

X

 

[AMRCN HP]

@AMRCN HP you wanna share your log with me and I can see if I can tell what it was doing? If the right PIDs were logged it'd be pretty obvious?

For you guys having this problem, what rear gear does your car have? 2.62 or 3.09?

The only time my car ever acted like the video Ron posted, I hit the rev limiter but torque mgmt would do it too. Rev limiter is easy enough to solve and it shouldn't be hitting it bone stock. Torque mgmt manipulation takes a little more thought as it is there to protect the car. Taking out some to fix an issue like presented is one thing, but take out too much and you're over stressing the trans.

Ron's video shows his 2018 Demon performing perfectly and it had 3.09 gears. His RE with 3.09s is falling over. I've got a 2019 RE calibration and a 2018 Demon calibration on my laptop, I'll look later today to see if I can see any differences in trans settings, torque mgmt, etc.

Sure, PM me your email and I can send you the logs for all 3 passes.

Paul...

 

[AMRCN HP]

BTW, 3.09 gears in my car with MT 315/50/17’s...

 

[Demoniccat]

3.09 here with the new nitto 555Rlls 315/35/R20 right now, probably going to a set of the MT 315/50/17 with set of wheels soon for track.

 

[EricG]

I have 2.62s fwiw

 

[Speedy!]

@AMRCN HP got your logs. There weren't any torque mgmt or transmission PIDs captured in the logs, but what I do see is the car shifted from 1-2 around 6100RPM on the first two runs and shifted early at 5400 on the last.

 

[jgilj]

@AMRCN HP got your logs. There weren't any torque mgmt or transmission PIDs captured in the logs, but what I do see is the car shifted from 1-2 around 6100RPM on the first two runs and shifted early at 5400 on the last.

Speedy’s the man!

 

[Speedy!]

LOL, I dunno about that. I'd like to see a log with some good trans data in it to understand why it shifted so early in the RPM range. That usually only happens if the tires break loose, which wasn't the case here.

 

[jgilj]

LOL, I dunno about that. I'd like to see a log with some good trans data in it to understand why it shifted so early in the RPM range. That usually only happens if the tires break loose, which wasn't the case here.

Speedy your a walking talking encyclopedia!

 

[Marc W]

LOL, I dunno about that. I'd like to see a log with some good trans data in it to understand why it shifted so early in the RPM range. That usually only happens if the tires break loose, which wasn't the case here.

I don’t know Jack but do you suppose that when the TM nanny pulls timing, that the tcm sees that as a signal to shift?

 

[Speedy!]

I'd think that unlikely but honestly with as sophisticated as these cars are anything is possible. I log transmission data in my logs that Mike from OST taught me about that show when it's commanding full power based on driver input vs reducing torque for torque mgmt or doing something due to ESP (electronic stability). Those things make it obvious what's going on and when and is a big reason I log all my track runs.

 

[TNREDEYE]

I don’t know Jack but do you suppose that when the TM nanny pulls timing, that the tcm sees that as a signal to shift?

Whenever I try to spin the tires in street trim(w 315/35/20 05Rs) it feels like the car will sense the rear tire acceleration to be happening at a rate that is 'too quick'. It seems to have little to do w how quickly the engine is revving, or at what rpm, it's much more like it's reading a driveshaft speed that's increasing too quickly as compared to what the car thinks it should be. In the car it very clearly feels like the engine is pulled way back and then the trans immediately shifts. Once the shift happens the power comes back pretty quickly and the tires are pretty well stuck.

My car has never done that w the 17" MT's on it at the dragstrip though so I'm at a loss as to why some cars do it on an otherwise good run and others don't.