2nd gear launch

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roccodart440

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I accidentally launched in 2nd gear the other day at the strip. It actually worked really well and put my ET exactly where is needed to be.

I was wondering if this is ok to do or if this would be harmful to the transmission.
 
If it is a manual valve body, I think you're ok......BUT.....Back in 2013 I ran my 10 second car in Sportsman for a season (12.0 bottom dial). I had to do all kinds of awful things to my car to get it to run consistent 12.0x's, one of which was I launched in second gear all season. At the end of the season, last race before the division finals my transmission burned up the clutches and went kaput (trans was 7-8 years old). A friend of a friend rebuilt it for me in 2 days and I got it back in the car for the division finals race....but....yeah, that was my experience with launching in second gear.
 
If it is a manual valve body, I think you're ok......BUT.....Back in 2013 I ran my 10 second car in Sportsman for a season (12.0 bottom dial). I had to do all kinds of awful things to my car to get it to run consistent 12.0x's, one of which was I launched in second gear all season. At the end of the season, last race before the division finals my transmission burned up the clutches and went kaput (trans was 7-8 years old). A friend of a friend rebuilt it for me in 2 days and I got it back in the car for the division finals race....but....yeah, that was my experience with launching in second gear.


I do have a manual VB.

What were your gears, converter and race weight?
 
About half a second.

If it were me I'd unhook the secondaries on the 4 bbl and see how close that gets you to your E.T. instead of leaving in 2nd gear. I'm not a trans guro so I'm not sure if it would hurt anything or not, we'll let them chime in. I just think that leaving in 2nd would build more heat and increase the wear and tear on the trans and convertor and make them fail sooner rather than later.
 
If it were me I'd unhook the secondaries on the 4 bbl and see how close that gets you to your E.T. instead of leaving in 2nd gear. I'm not a trans guro so I'm not sure if it would hurt anything or not, we'll let them chime in. I just think that leaving in 2nd would build more heat and increase the wear and tear on the trans and convertor and make them fail sooner rather than later.
I agree, pulling the secondaries would be a safer way to slow down...and just a side note, I tried this too in my search for a 12.0 ET years ago. Unhooking the secondaries got me almost half a second (about 4 tenths).
 
I'm no transmission guru either but i thing the biggest problem would be heat! And, getting it out of the transmission between rounds.
The converter is making a lot more heat.
Some may say that its no different then a 2 speed auto. but I would bet that even the tallest first gear set up in a two speed is still lower the 2 gear in a 3 speed(727/904)
AKA a clutch that is engaged before the launch has a better chance of staying engaged then one that has to slip into gear or clutch engagement.

I think the 2nt gear clutch is not the concern or issue
 
On poorly prepped tracks where I was traction limited, I’d start in 2nd gear. I’d ET around the same time but would be reving real high as I crossed the traps.
727 RMVB with a TB and 3:55 gears.
Trans heat was never an issue for me but I wasn’t one to “hot lap” either. Lol
 
So let’s say I’m racing the 1/4 mile.
I’d normally be shifting to 3rd at the 1/8 mile.
Now let’s say I’m racing the 1/4 but starting off in 2nd gear. I’d still be shifting into 3rd around the 1/8th mile, effectively running out of gear well before the 1/4.....
I guess running 6PSI of boost and a 150 shot of Nitrous would effectively pull me through the torque converters torque multiplication in 1st gear..... and in 2nd and 3rd for that matter with both power adders.
Ultimately I’m trying to cover 1320’ in two gears as opposed to three gears.
It’s not like I set up the rear gear ratio, tire diameter for a PG 2sp trans.....
I’m “ideally” set up for a 3 speed, pending track prep....
 
My trans brake will work in first or second. My car went 6.52 with a 1.50 60' leaving in second. At the time it was going low 6.40's and low 1.40's.
 
My trans brake will work in first or second. My car went 6.52 with a 1.50 60' leaving in second. At the time it was going low 6.40's and low 1.40's.
Soooo
Would you be RPM higher, at the finish line when you launched in 2nt instead of 1st?
 
I am missing something here ....
How does leaving in 2nd raise your rpms ? If anything you should be running less rpms at the end .

Run this by me again .
 
I am missing something here ....
How does leaving in 2nd raise your rpms ? If anything you should be running less rpms at the end .

Run this by me again .

It doesn't. It would either be the same RPM or lower because you made a slower ET run. You will still shift at the same RPM's which occur at the same speeds. Everyone runs a slower ET when launching in 2nd gear, hence less RPm through the traps.
 
I'll try disconnecting the 4barrels. I do not have a cage and the car goes 10.90's. This is why I need to slow it down.

WOuld this cause a lean issue?
 
I'll try disconnecting the 4barrels. I do not have a cage and the car goes 10.90's. This is why I need to slow it down.

WOuld this cause a lean issue?
I don't think so, I have a wideband on my car, and the AFR stayed about the same.
 
I'll try disconnecting the 4barrels. I do not have a cage and the car goes 10.90's. This is why I need to slow it down.

WOuld this cause a lean issue?

No cage or no roll bar? Need a roll bar at 11.49 and a cage at 9.99 last time I checked. If your doing 10.90s and need to go 11.50's, def unhook the 4 bbl. We did this with my wifes car and it was darn near spot on 6 tenths slower. If when you unhook the 4 bbl it still a tad quick can always add some weight in the trunk. We also wired the 4 bbl shut as I've heard that at times they can slightly open going down track due to the air, but not sure if that's true or not.
 
We also wired the 4 bbl shut as I've heard that at times they can slightly open going down track due to the air, but not sure if that's true or not.

The theory is right, as the butterfly is off set to hold it closed..........However, if it did open it would not shut until you turned the ign off:steering:
 
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