Talk me into a transmission change...

[cjshaker]

Eric, Jay is talking about the lost RPM that he's seeing at the top end. Lost RPM is lost speed and ET. A Gear Vendors used in that way would probably cause the convertor to slip more, just making the problem worse, but that's just a guess.

I've been studying up a bit over the last few months on different manuals for my next build. I still have more learning to do, but have figured out a few things. I don't think the Liberty is the way to go for anything but a strictly flat out straight line racing car. A slipper clutch isn't ideal for the street, but if it's used properly (read: judiciously) it won't give you any problems. Just don't consider it a 10 year clutch. Once a slipper clutch is dialed in, and it isn't that difficult with good guidance, it is a solid design that only requires minimal adjustments that are also easy. Slipper clutches also make driveline breakage much less of a problem because it softens the torque application.

I was also considering a Lenco. The things are bullet proof, easily rebuilt and not complicated (but there are some tricks to learn). There are guys running Lencos on the street, with differing approaches. Air shifting on the Lenco, which I believe will hold them in gear, is a consideration, but after seeing the solenoid setups used for air shifting, that thought would disappear quickly for me. Some guys just hold them in gear so they don't pop out on the street, or push the clutch in before deceleration which stops the momentum from pushing them out of gear. I don't like the idea of riding a clutch because it wears out the thrust bearing, not to mention the throw-out bearing...and your leg. Holding it in gear is not that big of a deal. Remember, if you have to get off the throttle for a second at the track, the run is basically aborted, or at a minimum you're going to lose a lot of ET, which basically means the run is worthless in the style of racing that you do. Edit: Since I never remove my hand from the shifter while I'm running hard, it would just be natural for me to hold it in gear until the next gear change, so having to let off wouldn't be that big of a deal.

While checking out Lencos and the advantages and drawbacks, I found this guy from Australia some time back. I REALLY liked this shifter design he came up with for the Lenco. It's been a few years since he designed it and from what I've found out, he's in the process of applying for patents to be able to sell in the U.S.. At least that's what he said on Yellow Bullet in his only posts earlier this year. I believe that his design keeps the Lenco from jumping out of gear, but I'm not 100% certain about that. Either way, it gave me ideas that it shouldn't be that difficult to design something that would hold them in gear until you "released" or "unlocked" them somehow.

https://youtu.be/07_y-svxn0M

Just some things to consider. You know where my vote lies

[e philpott]

for what he's asking the ATI Power glide with Lock-up torque converter would probably work best  , would basically work like it is now except for the Lock up , it sure would hold the power ...... either way it's fun spending Jay's money

[427Fastback]

I will never own anything that has a lenco trans but I find that V-gate style shifter very interesting.....OK..I find the mechanics of it very interesting..

[IDOIT4SPEED]

hi this will be my third season drag racing with a lenco st1200  they have some odd features. four speeds forward, four speeds in reverse.  they can be leak prone they do not have a vent, installed a remote fill tank with a vented cap, no more leaks. they use cheap 10/30 oil for lube. they do not jump out of gear. they have no engine braking except in high gear. they have sprags in the planetary gear sets. in my car if I drive in low gear at 4500rpm about 15 mph, and lift off the throttle the engine will go to idle and the car will coast as if it is in neutral. it will do this in all gears except high gear where all clutch packs are locked up and is in direct drive. with this in mind if you have to lift during a race in the lower gears, your run is over. gas pedal games in high gear only. driving around I find myself throttling and coasting all the time. also the shift levers can be pulled in any order when just driving around.   mike

[jayb]

Hey Mike, welcome to the forum and thanks for the clarifications on the Lenco.  I must have misunderstood when we talked on Saturday about the transmission jumping out of gear.  So, let's say you are running down the track in second gear and you lift, and the engine goes to idle.  I assume that you can get right back on the gas without damaging the transmission?

Sounds like the part throttle operation (throttle, coast, throttle, coast) would be kind of annoying but at least livable on the street.  Do you ever get any street miles on your car?

Also, you mentioned that it is a heavy transmission.  Any idea how much it actually weighs?

[shady]

Hey Jay, so I had a talk today with a friend of mine who has an all steel 55 chev. with a N.A. bbc in it. It's making over 1100 hp. & runs mid 8s. he is running a lenco 4 sp. with an adj. singe disc clutch. says it jumps out of gear in all but 4th. drag races it mostly, but is street driven & is street legal. If you want I can get you a phone # and you could talk to him about the set up & all the nuances.

[jayb]

Well, that's interesting.  Maybe under certain circumstances they will come out of gear, or maybe he just means that the sprag is free wheeling in that case.  Thanks for the offer, if I decide to go forward with the Lenco I'll get back to you for your friend's number.

[cjshaker]

I'm not sure how Mike's is set up, but there are plenty of videos showing all the levers popping forward when letting off the gas, putting them in neutral. Making a locking pawl for each lever would not be overly difficult. Something with a release lever on the grip like the V-Gate or the one shown in the video. I'm surprised I haven't seen something like that already.

[XR7]

I've never heard of Lenco's "popping" out of gear. They have a one way clutch, and a high and low for each gear, that is what is shifted on each unit, compounding each ratio. The lever on the main unit id basically just forward and reverse and nuetral. Yes... it is possible to have 4 reverse ratios depending on how many levers are pulled in when the main box is in reverse.

Like what was said, when you let out of the gas at the top of a gear, the engine will go to an idle and "free wheel" where there is no engine braking. It is still in gear... I have two friends that race with Lenco's in 8 second cars, neither has ever had them pop out of gear. I think in high gear, it does have engine braking (not 100% sure...). Another guy has one that he drives on the street a fair amount, as well as races, running low 9 second passes.

You can upshift or downshift, with or without the clutch! One thing wierd is when the car is parked and engine off, and in any forward gear, it will roll forward if on a hill for example, to stop that you put it in reverse, and it won't roll forward (it can roll backward though!).

If I were you Jay, I would call Lenco and talk with them, get info from the horses mouth. Another option may be the "Jeffco" trans, which is very similar to the Lenco by design.

For the Liberty equalizer clutchless 5 speed, you do have to hold the shifter to keep it in gear in 1-4, in 5th gear it will stay in gear without holding the shifter... but if you let out fo the gas it will go to nuetral in any gear (I think even in 5th but not 100% sure...).

Clutch tune can be tricky, it would take some time the first time, then after broken in and a baseline set-up, wouldn't be too hard to adjust for race or street duty. I can adjust mine by myself in between rounds, maybe 6-8 minutes. Some guys run a stiff enough tune that you wouldn't need to adjust between street and drag, other combos may need a pretty good adjustment if on kill at the track.

[jayb]

I wonder if the popping out of gear issue is related to a race Lenco vs. their street unit.  I think Mike has the street unit.  I'm sure XR7 is right, best to just call Lenco and ask...

[XR7]

I don't think so, two are the ST1200 street trans and the other is an old CS1 race trans that will support 3500 HP. I will admit I haven't driven any Lenco's, and even called and asked one guy with a ST1200 a few minutes ago, he said it has never popped out of gear. He said he has "peddled" it in 3rd gear, and it stayed in gear.

It may just be the "free wheel" thing and different people call it different things, nuetral or out of gear, etc.   Not sure...

I have never seen a video of the levers popping forward, all that would do is go from 1 to 1 to the lower ratio of that gear, or all gears (back into first gear) I don't think that is possible. You have to push (almost hit) the lever hard to get it to lock back into "low" gear (each gear lever), the forward/reverse/nuetral lever has detents to hold/latch it in, and you have to raise the selector to get it in and out of gear, so that isn't "popping" out of gear...

As for weight, I believe the 4 speed is 154 pounds and the 5 speed is heavier yet, they just get longer and heavier as you bolt on more (units) gears.

[shady]

I may see him again tomm. he pops in the local coffee hole usually every morning. I will ask him about the popping out, he may have meant free wheeling.
I know he's already had sprag issues, but I am pretty ignorant on these trannys.

[XR7]

My buddy with the old CS1 race unit has run his for over 25 years and I don't know how many "thousands" passes. He broke a sprag in the high gear unit and that is all he has ever broke. Lenco chewed him out and said the only time that breaks is because of doing the burn out wrong... (he was). Basically the high gear has to be engaged 1 to 1, and any or all other levers can be forward. He had 2nd and 3rd levers back, but not 4th. Now he uses 4th and 3rd back, and leaves second gear forward and it is like being in 3rd gear (ratio and wheel speed) during the burnout.

It is kind of strange that you can pull 4th gear lever (only) and really it will be like in second gear as far as the ratio. Each unit can have a different ratio, and all together add up to the first gear ratio, so you can have different "splits" depending on which ratios are used, and which levers are pulled back. Oh yeah... and 4 reverse gears if needed, LOL.

[IDOIT4SPEED]

Hey Mike, welcome to the forum and thanks for the clarifications on the Lenco.  I must have misunderstood when we talked on Saturday about the transmission jumping out of gear.  So, let's say you are running down the track in second gear and you lift, and the engine goes to idle.  I assume that you can get right back on the gas without damaging the transmission?

Sounds like the part throttle operation (throttle, coast, throttle, coast) would be kind of annoying but at least livable on the street.  Do you ever get any street miles on your car?

Also, you mentioned that it is a heavy transmission.  Any idea how much it actually weighs?

the throttle and coast thing might be good for rolling  burnouts. I have not tried that yet. once you get used to it its not bad to drive. the most annoying thing is how hard you have to hit the levers to get it out of a gear. I cannot push a lever to get it out of gear. a thick padded glove might help.  more later mike

[shady]

OK, talked to john this morning, he said if you leave off in 1st 2nd, or 3rd. tranny free wheels, levers don't move, 4th stays in gear. when free wheeling, you can bring rpms back up & re-engage but is a bit tricky as to not dickup the sprags. takes a bit of practice to street drive it. on the track, you can lightly lift to pedal it a bit, but not really get out of it. weight is 140#s. hope this helps.