2nd Gear Launch, When to Hit Lockup?

[IOWA LLY]

I tried searching and didn't find much. So I apologize if this has been covered before.

I'm going to the drag strip again this Friday and will be running a manual lockup switch for the first time. I ran a 6.72 at 106MPH last Friday but couldn't back it up. I believe one of the reasons is lack of consistency in allowing the TCM to handle lockup on its own.

My question is this, how long should I wait to hit the switch after releasing the brakes? Is there enough "delay" in actually achieving lockup that I can hit it right away? My truck takes off like a rocket now when it locks up, but the TCM wont lock it until its a ways out. I leave the line in 2nd gear at around 32-3400 RPM and 50 PSI of boost. I feel like I could hit the switch almost right away but I would like to hear some other opinions.


Thanks.

 

[quinton]

I lock mine right off the line. Mine is manual switch. No problems here.

 

[gl4787]

Launching in first I always hit the lock up as soon as I left the line and it always locked perfectly right into 2nd. I'll be going to a second gear launch next time I hit the strip and would like to know also.

 

[Chevy1925]

sounds like that converter isnt coupling for shit if lock up makes that big of a difference. id hit it right out of the hole and see how you like it. you may or may not blow the tires off but only one way to know!

 

[quinton]

Curious what you're setup os

 

[Evan@InglewoodTrans]

sounds like that converter isnt coupling for shit if lock up makes that big of a difference. id hit it right out of the hole and see how you like it. you may or may not blow the tires off but only one way to know!

Unfortunately for now even the most efficient higher stall converters with medium duty pumps still can't wait to be locked to start putting power to the ground in high HP applications. That's in the process of changing though and there will be some new high efficient options to choose from for drag race applications.

 

[IOWA LLY]

Curious what you're setup os

Still my old 2011/2012 pulling setup. 3.42 gears, billet wheel HX 60 with a 3" compressor inlet. 3.6" turbine exducer. That's why I need so many RPMs on the line. Make she most power from 3100-3500 once lit though. That's why it pulls so much harder after it locks I think.


Sent from my iPhone using Tapatalk Pro

 

[IOWA LLY]

I lock mine right off the line. Mine is manual switch. No problems here.

1st or 2nd gear launch? Can you feel much delay from when you flip the switch to when it locks? Or does it feel like it locks almost instantly?


Sent from my iPhone using Tapatalk Pro

 

[IOWA LLY]

sounds like that converter isnt coupling for shit if lock up makes that big of a difference. id hit it right out of the hole and see how you like it. you may or may not blow the tires off but only one way to know!

I'm switching converters right now.


Sent from my iPhone using Tapatalk Pro

 

[quinton]

1st gear, will be doing second gear soon. With the first gear start it locks almost instantly, hard to tell because it shifts into second also. With second gear it should lock as soon as you flip it. I've played with it in gears driving down the road under throttle and locks when I flip it under any throttle position.

 

[Chevy1925]

Unfortunately for now even the most efficient higher stall converters with medium duty pumps still can't wait to be locked to start putting power to the ground in high HP applications. That's in the process of changing though and there will be some new high efficient options to choose from for drag race applications.

are they that bad to be putting that much boost out and still be lazy daisy like that off the line? im guessing its converters that need a stall over 3k or are lower ones still the same?

 

[gmduramax]

James I don't think there'll ever be a converter that couples as good as being locked up. I literally take my foot off the brake and lock the converter.

 

[IOWA LLY]

James I don't think there'll ever be a converter that couples as good as being locked up. I literally take my foot off the brake and lock the converter.

2nd gear launch?



Sent from my iPhone using Tapatalk Pro

 

[gmduramax]

2nd gear launch?



Sent from my iPhone using Tapatalk Pro

First gear 3500 stall converter 80mm single. I have lots of traction. Had a shitty 60 foot but
60 1.62
330 4.54
660 7.0 @100

 

[Ne-max]

I got it at the 60ft mark or when I am comfortable taking a hand off the wheel. My truck does not like lock up out of the hole. I've been cutting 1.55 60fts lately. 2nd gear starts. Dhd lock up

 

[SickLL7Crenshaw]

I hit lock up approximately 35-40ft out of the hole. We fisnlly pulled a 1.56 60' out of my old CC/SB Gold truck, modded stock/s480 setup with a 1055. 6900lbs. 2nd gear launch.

 

[prostreeter600]

From personal expierence I would say it depends on your power level and if your launching on top of your chargers . If the tires hold I would say lock it up as soon as you launch it if your on top of your chargers when you launch . I tried locking mine up as discribed but my tires wouldn't hold . I had to put it on the automatic lockup mode . My best 60' has been on tune 3 with 2nd gear launch . Tune 4 and Tune 5 netted slower and slower 60' due to tire spin.

 

[nmband13]

I hit my DHD lockup in the first 30ft and cut 1.55-1.58. Any longer than that and 60' turns into 1.6-1.63...my lockup takes approx .2 seconds to lockup, quicker than I can hit lockup and put my hand back on the steering wheel. I can't leave the line above 40psi/2900rpm otherwise it'll spin all 4 M&H radials on a minor prep track. I don't know how you leave at 3200rpm/50psi without blowing the tires clean off.

 

[IOWA LLY]

I hit my DHD lockup in the first 30ft and cut 1.55-1.58. Any longer than that and 60' turns into 1.6-1.63...my lockup takes approx .2 seconds to lockup, quicker than I can hit lockup and put my hand back on the steering wheel. I can't leave the line above 40psi/2900rpm otherwise it'll spin all 4 M&H radials on a minor prep track. I don't know how you leave at 3200rpm/50psi without blowing the tires clean off.

Are you launching in second gear? I have 3.42 gears also. That helps I'm sure.


Sent from my iPhone using Tapatalk Pro

 

[IOWA LLY]

I switched to a Suncoast 1053-2 last week. Last night I ran 3 consecutive 6.6 second passes. Ranged from 6.60-6.64. I like this converter the best of everything I've ran so far. Cut a 1.58 60' time on street tires. Before my best 60 was a 1.66.

I had to lower my launch RPM because he first pass we blazed the tires with this converter. 3200-3300 seemed to be the sweet spot.

Lockup was basically just done by feel as soon as it got out of the hole. It's hard to be scientific about it.


Sent from my iPhone using Tapatalk Pro