O/T for sure: when did Pro Stocks switch from Lencos to stick transmissions?

[machoneman]

Did NHRA ban Lencos or was it merely the fact that modern stick trannys ate less hp?

Remember well the old days when pulling a Lenco for adjustment and/or a gear change was a regular feature. All those fish scales to test the draw on each section was pretty cool too!

[Rory428]

Pretty sure the reasons the Pro Stock teams switched from Lencos to geared transmissions was less internal drag as well as lighter weight. I was talking to a fellow Ford racer, who until recently raced a Comp Eliminator Ford Probe, as well as a 8 second 67 Fairlane, and he told me his old Lenco 5 speed was about 8 hundreths slower in the 1/4 mile than his current Liberty clutchless 5 speed. In Pro Stock, that .08 can mean the differance between qualifying in the top 1/2 of the field, and not qualifying at all.

[machoneman]

Thx Rory! I had heard some of the same but wasn't sure. Yes, that lesser drag and reduced weight does make a diff!

[BattlestarGalactic]

I've heard that a lenco can be a 1-3 tenths slower then a gear transmission.  We have a few running in our group, as it is a much cheaper alternative to a Liberty Equalizer.

I didn't watch drag racing that much growing up.  I do vaguely remember air shifters then they went back to a handle.  I have no time line for any of it though.

[machoneman]

Air shifters were a neat addition to a Lenco. In Pro Stock's heyday though (70's) I don't ever remember seeing those teams using an air shifter, just the multiple levers. Perhaps that invention came a bit later.

[gt350hr]

  It was in the late '90s. Planetary transmissions are never as efficient as "normal" gear to gear transmissions. The Lenco became the "standard" because it was virtually bullet proof at the "in the day" power levels. Manual transmissions could not stand up to the power. Jerico and Liberty pioneered they technology to shift better and be more durable along with faster serviceability. A modern Liberty can get a gear ratio change in about 30 minutes or less which is a MUST with today's 45 minute turn around requirements. Lencos ( with 5 forward speeds are over two times as long as a Liberty 5 speed. NHRA only restricts the amount of forward gears to five max.

[Posi67]

My 10 year old rulebook indicates that Lenco's were still legal however I do recall a rule change at some point that air shifters were not permitted. Warren Johnson was one of the supporters of shifting gears manually. More research needed to find the time  line. 

[cjshaker]

Not a fan of air shifters. Might as well use a neutermatic.