FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: jayb on October 04, 2015, 12:32:15 PM
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I have been giving some consideration to a transmission change in my Shelby clone. The ATI Powerglide that is in there now was originally purchased for my Galaxie, where I plan to put another SOHC and two turbos to make 1800 HP or so. The ATI trans is supposed to be good for 2500 horsepower, so it was a good plan for the Galaxie, but is way overkill in the Shelby clone.
When I originally built the Shelby clone, the plan was to go to one of those street Lenco transmissions. But, at the time they were outlawed at Drag Week in all classes except for Unlimited. And I had the ATI trans just sitting there, so I bought a converter and put it in the car. I've been running it there ever since.
In the meantime, I've learned more about Lencos, and have learned to like them a little less. One thing that I don't like is that I've been told that they use a lot of power. This makes sense to me because they are a planetary gear setup, and as you go down the track, you are just subtracting more gears. Its not like a regular manual transmission where you are changing from one gear set to another; each module of a Lenco has a direct drive and an underdrive module, so when you shift the first gear module you might be shifting from a 1.37:1 ratio to a 1:1 ratio. This means that if you are running a four speed car, at launch you have three gear sets engaged. When you do the 1-2 shift, you reduce that to two gear sets, the 2-3 shift reduces it one, and the 3-4 shift gives you direct drive. All the gear sets engaged simultaneously will eat some power.
Yesterday one of the guys who did the machine work on repairing my Shelby block came by for a visit. He has a 67 Mustang with a 347 Windsor engine that runs mid 10s. He used to have a G-Force trans in the car, but it kept breaking, so he switched to a Lenco. (It surprised me that a G-Force trans wouldn't take the power required for a mid 10 second pass). He said that he didn't see a loss of power when he switched to the Lenco, but he wasn't 100% sure because he didn't have back to back data to say definitively. I do know that when the Pro-Stock teams switched from Lencos to Libertys they picked up quite a bit, so at least compared to a Liberty the Lenco will eat some power.
He also told me about the issue with Lencos coming out of gear when letting off the throttle, which I didn't know about. I knew that Libertys did that but I didn't know Lencos did it too. So, if you are on the track and have to let off for a second your pass is over, driving around the pits and doing the burnout requires some special procedures, etc. After talking to him about his Lenco for a while, I kind of decided that it was not for me.
At Drag Week, Joel's trunk monkey Jeff (JericoGTX on the forum) mentioned that Liberty now offers a trans with a synchronized fifth gear, so that in fifth the transmission won't pop out of gear when you let off the throttle. I haven't been able to find any mention of that on their web site, though. If that option is available, at least freeway driving would be tolerable with that trans. But it would still be a pain around town.
A G-Force or a Jerico would be a better solution, but they aren't going to hold up in a 3250 pound, high 8 second car. I think my only options for a manual trans are the Lenco and the Liberty. Anybody else know of any other standard transmissions that will take 1000 HP and are streetable?
Next consideration is the clutch. Mike, the guy from the machine shop who visited yesterday, figures that it takes a whole racing season to really dial in the clutch setup. You've got preload pressure and centrifugal weights to worry about, you are drilling holes in the scattershield and have the car up in the pits to make adjustments, etc. etc. This is a problem for me because I just don't know much about modern clutch setups, so I'd be starting at the bottom of the learning curve. A friend of mine just spent $4K last year trying to figure out the clutch in his stock eliminator car. Doesn't sound like much fun to me.
As opposed to a manual trans, my ATI trans is trouble free. I just drive the car, on the street and on the track. At the track, I'm not constantly shifting gears; one shift at about 400 feet and I'm done. It is easy, easy, easy, and with so many other things to worry about on the car, its nice to not have to think much about the transmission.
But here's what I don't like about it. My datalogs from Drag Week say that the engine is turning 7700 RPM through the traps, but at 150 MPH, the driveshaft is only turning 7250 or so. I am losing 400-500 RPM in the torque converter. I don't like that one bit >:( Which is why I'm still thinking about going through the trouble of switching to a manual transmission.
Anybody got any useful suggestions on how to overcome the manual transmission hurdles that I've detailed here?
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I'll be the nay-sayer...
With all the respect in the world, most every race has been last minute with an engine hot off the dyno. If you continue that trend, that means minimal clutch testing, minimal practice driving the car, not to mention a suspension that will be shocked much differently.
I personally think that researching a more efficient AT would match your needs better, if those needs stay the way it has been.
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With all the respect in the world, most every race has been last minute with an engine hot off the dyno. If you continue that trend, that means minimal clutch testing, minimal practice driving the car, not to mention a suspension that will be shocked much differently.
I personally think that researching a more efficient AT would match your needs better, if those needs stay the way it has been.
That's a fact, Ross; despite my best efforts it seems to be a last minute deal every year. Point for the automatic, that's for sure.
Maybe I should just be talking to the converter folks...
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Ive seen c4's capable of over 1500 hp
And My427Stang Makes some good points
They make some amazing converters for the pro mod guys
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Jay,
Unfortunately, I would stick with the glide if I were you. You start adding more gear reduction to a car that I believe is still somewhat traction limited. Your not gonna go any faster unless you can get the power to the ground.
I would just pull some more gear out of the car to bring the Rpms down a little. Go to a 4.10 or 3.89 gear or try a different converter/ converter company. I believe you still have a few tenths to find in current setup. The glide is one of the most efficient transmissions made. I also wondered why run the the gear vendors in a car with that much power. I'm sure it eats some horsepower itself.
My plan for my truck was just to build a stout engine and automatic trans. Run a 3.89-4.10 gear and 30-31 inch tall tire with no O.D. With converter slippage the 70-80 mph cruising rpm should be very tolerable on the street. Less gear reduction should make it a little easier for the chassis setup to get the power to the track. Anyway, just my two cents worth.
After following drag week coverage this year I see I will have to put a roll bar in my truck and run bottom 11's to mid 10's to have a chance at the 32 car field bracket race on the final day.
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is there not a lockup convertor available for the 'glide to bring the revs down at the top end?
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First---my 1.5 cents worth. I, too, would look further into the converter situation.
Second, I'd like to know more about the 'popping out of gear' with the Lenco. I don't see that there is anything inherent in a planetary set-up such that a coast situation doesn't work. But maybe I just don't know.
TIA for any further enlightenment.
KS
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Ive seen c4's capable of over 1500 hp
Where? From what I've been told pushing over 900 HP in a C4 is asking for trouble...
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is there not a lockup convertor available for the 'glide to bring the revs down at the top end?
The lockup converters that I know about won't take the horsepower. But maybe there are some I don't know about that would work. More research, I guess...
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I'm no expert on Lenco's, but I do know there is one in Larry Larson's Nova and he's done ok at Dragweek, must be streetable somehow.
(http://i1235.photobucket.com/albums/ff437/red0wl/Larry%20Larson%201.jpg) (http://s1235.photobucket.com/user/red0wl/media/Larry%20Larson%201.jpg.html)
Horsepower drag was only one reason NHRA Pro Stockers went away from the Lenco and the resulting ET improvement - overall weight reduction was one and the desire to keep the engine in a narrower powerband was another.
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Jay,
Who is supplying your converters? I use Ultimate Converter Concepts. They have built a lot of converters for the guys on the 460 sites I frequent. A lot of the 460 guys making 1000+ hp are using aftermarket glides and UCC converters. I told UCC what I was trying to do with my truck and I've been very happy with the results. They use something called a mechanical diode in the converter that is supposed to help with lockup on the big end. They are expensive but I believe ya get what ya pay for when it comes to converters. A lot of low nine, eight, and seven second N/A and nitrous drag cars using their converters and glide transmissions. I've also heard that much past 800 hp the C4 transmission is unreliable.... They need to be freshened often at that power level if they hold up at all, just not enough clutch pack holding power. I don't think that would be a wise move in a drag week environment.
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I'm no expert on Lenco's, but I do know there is one in Larry Larson's Nova and he's done ok at Dragweek, must be streetable somehow.
Well, if I wanted to deal with the trans popping out of gear every time I took my foot off the gas while going from one track to another, I could run a Liberty or a Lenco at Drag Week, but I just would rather not. At that point I'd live with the automatic.
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Jay,
Who is supplying your converters? I use Ultimate Converter Concepts. They have built a lot of converters for the guys on the 460 sites I frequent. A lot of the 460 guys making 1000+ hp are using aftermarket glides and UCC converters. I told UCC what I was trying to do with my truck and I've been very happy with the results. They use something called a mechanical diode in the converter that is supposed to help with lockup on the big end. They are expensive but I believe ya get what ya pay for when it comes to converters. A lot of low nine, eight, and seven second N/A and nitrous drag cars using their converters and glide transmissions. I've also heard that much past 800 hp the C4 transmission is unreliable.... They need to be freshened often at that power level if they hold up at all, just not enough clutch pack holding power. I don't think that would be a wise move in a drag week environment.
I've been using Neal Chance Racing Converters; haven't looked at UCC. I'll check them out.
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Yikes, a tough question for sure.
-As noted, last minute dyno sessions and little track testing time IMO almost rule out any stick tranny save a Lenco (later). Larry Larson or other high hp Lenco users should be grilled.
-no true stick tranny as stated will survive 1,800 ponies, for sure.
-mechanical diodes could save lots of convertor slippage and they ain't cheap. Yet, no idea on their longevity before replacement and that can't be cheap either.
-Lencos would not, under a high hp engine as planned, require a 'lot' of clutch tuning when compared to a true stick tranny/slipper clutch setup. Yet, it would require some.
-Now, once dyno testing is done, I'm sure you slap the motor in and go with your 'Glide. Bluntly, no time for clutch testing =no Lenco in my book!
Maybe......investigate the mechanical diode, add same if warranted, change gearing as noted and keep the 'Glide. I do like the Lenco idea though and with 1,800 hp the hp loss IMO would be negligible. Keep in mind those 1970's 750 hp Pro Stockers of the era lost only a tenth with a Lenco due to internal power absorption (or gained a tenth when switched back to a stick tranny). With almost 2.5 times the hp, I doubt you'd loose even that tenth. Then again, one never misses a shift with a Lenco and they are easy to repair...although they never break, they just need occasional clutch pack replacement. One more benefit: changing gear ratios, 1st or high gear or both is a snap.
They also allow a MN guy to use his fish scale more often!
Btw, you should peruse the Top Alcohol and Pro Mod sites (no kidding!) for Lenco, Bruno, Coan and other trick tranny setups, opinion, etc. JMO!
http://www.insidetopalcohol.com/showthread.php?17696-Transmission-Bruno-or-lencodrive
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Second, I'd like to know more about the 'popping out of gear' with the Lenco. I don't see that there is anything inherent in a planetary set-up such that a coast situation doesn't work. But maybe I just don't know.
TIA for any further enlightenment.
KS
That was a new one on me too, Ken; maybe I just didn't understand what Mike was saying. I'm going to have to ask him about that to confirm...
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isn't the popping out of gear for the "clutchless shift" models only and not the regular face plate deal ?? ..... road racers don't have a problem...... manual wise you have to have something face plated at the minimum or you can't hit the gears
B&M does have a PG with lock up converter that's supposed to be a 3000 hp transmission , big money but makes all other PG's look like toys
I don't get how the Lenco pops out of gear anymore than a Gearvendors
for the soft lock clutches you need a data logger to speed up the learning curve , having Tim Hyatt's phone number sure wouldn't hurt either for a good base line and technical info
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The face plate lugs should be similar to the one below. This is what I have planned for my toploader when the time comes. Notice the lugs have a tapered edge to hold them together to prevent popping out of gear.
(http://i12.photobucket.com/albums/a232/jaredaebly/Mobile%20Uploads/Faceplated%20Toploader_zps2mzqadbe.jpeg) (http://s12.photobucket.com/user/jaredaebly/media/Mobile%20Uploads/Faceplated%20Toploader_zps2mzqadbe.jpeg.html)
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isn't the popping out of gear for the "clutchless shift" models only and not the regular face plate deal ?? ..... road racers don't have a problem...... manual wise you have to have something face plated at the minimum or you can't hit the gears
B&M does have a PG with lock up converter that's supposed to be a 3000 hp transmission , big money but makes all other PG's look like toys
I don't get how the Lenco pops out of gear anymore than a Gearvendors
for the soft lock clutches you need a data logger to speed up the learning curve , having Tim Hyatt's phone number sure wouldn't hurt either for a good base line and technical info
According to Liberty when I spoke with them about this a few years ago, all of their 1000+ HP transmissions will come out of gear on decel.
A Gear Vendors overdrive uses a cone clutch, completely different design than a Lenco.
I wasn't aware of that B&M transmission Eric, I'll look into that one.
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the lock up is built for the application in the ATI , the more horse , the more lock up clutches ...... the more the lock-up clutch's , the more require extra adapter plates to allow room for the extra long converter , it spaces the trans back for the extra clutches in the lock up unit
it's not B&M but ATI
http://www.atiracing.com/products/trans/pg/index.htm
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My opinion:
Use a tranny that is reliable and consistent. You're talking about racing, not just having fun. I know at your level this may sound crazy, because you have certainly raised the bar, but it's still simpler and better to increase hp or reduce weight, rather than monkey-ing around with fancy, and more complex (broken), transmissions. You have so much power to weight that, in my mind, mechanical efficiency is not the prime consideration. Putting the power to the ground consistently is. If mph at the traps were the issue, then I might say something different.
If you can get a lock-up convertor to work, great. If not, focus on hp and weight, or a different conventional torque converter.
JMO,
pauiie
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Dragzine on Pro Mod 'Glides:
http://www.dragzine.com/tech-stories/drivetrain/how-3000-hp-capable-pro-mod-powerglides-are-built-at-ati/
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Aren't there any 9-second Super Stock cars running C6's? Seems to me that's the wavelength to be on.
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Ring out the combo you have now.There IS more in it.
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Seems simple for me....
If you want to keep racing it like you do, stick with what is already working for you transmission wise. Just tinker around with the converter for changing mild effects.
If you wanted to just drive it around and weren't so serious about ET's a c6 is a no-brainer. Don't believe the c6 is used in racing? try visiting the 460 forum sometime :P Some of those boys have obnoxiously powerful car with a c6 behind it.
otherwise I'm with LimaBean, I mean, your car is fantastic, but it is still kinda sorta a new build, tuning wise.
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Ring out the combo you have now.There IS more in it.
I'm on the side of Lima Bean's advice, but for the purposes of this discussion...
Aren't there any 9-second Super Stock cars running C6's? Seems to me that's the wavelength to be on.
Most of the fast Ford FE Stock & Super Stock racers have been running the ProTrans, C6 case with custom internals based loosely on the torqueflight. I'd certainly talk to them, not sure if anyone is running them past the 1000hp level. Their website can be kind of hard to find, lots of companies with the same name. Here's a link:
http://www.protransracing.com/index.html
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I don't have a super stock car but I do have a 2550 lb all moly falcon with a c6 and a 482 pond motor. it ran 9.45 and I know theirs more in the car. but when I was getting into this stuff long ago that was all their was for the fe, other than a 4speed. this off season I am looking to upgrade to a p/g I am going to swallow my ford pride and just do it, im to the point where I just want to go rounds and put chevys on the trailer. the learning curve is finding the right convertor combination that the car likes as we all know. that being said Im pretty safe in saying jay that you have had your engine dynoed also. it was the best 1000 bucks I have ever spent on this car stuff, barry did it for me when he built this motor for me. what is the greatest is I called coan told them all the car weight hp etc etc and sent them dyno sheets and wow that convertor doesn't miss a beat it locks up where it should and I only had to buy 1. I believe you should play around with different convertor stalls(obviously) before you spend all that money on a stick tranny jmho. no offense stick guys. a friend of mine uses frank lupo convertors and I am very impressed with those also just food for thought. plus if you do get rid of that glide you have I would definitely be interested in it. :)
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One issue I'd see in Jay's situation, switching to something like the ProTrans, is I don't know that there is an aftermarket SFI C6 case ( and bellhousing ), that means adding a transmission shield and flexplate shield and that means probably adding more weight along with the hassle and drivetrain clearance issues. It would be a question I'd ask.
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Hmmmm, to me this appears to be a perfect time for Jay to get his dyno to attach to the output shaft of a transmission or 1350 yoke.
"The Great Transmission Comparo"
(sure would put a heck of a lot of myths about consumed HP to rest)
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that's what stinks about the c6 also is the flex shield for the fe isn't even close to fitting and its a tci, I had to cut off half the tabs and re weld to fit the fe, also the transmission shield that ati has is about the same bad fitment for the fe also, (at least its aluminum) :) also the weight savings on the powerglide as opposed to c6, that's a big chunk saved because you can just have them build it in the sfi case and no more shields :D
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Jack Miller uses the gear vendors to control down track rpm on his PG
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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 ;)
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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 :)
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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..
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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
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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?
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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.
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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.
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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.
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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.
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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...
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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.
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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.
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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.
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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
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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.
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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.
Interesting info on the staying in gear. Guess I need to research it better. But I can vouch for the messing up sprags by unloading them and hitting them hard again with throttle. Some of the old flathead trannys will freewheel when off the gas, you need to bring up the rpms and engage them without "hitting" them hard. It's just the nature of sprag bearings or clutches.
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jay; I still think playing with convertors is a better cheaper idea. I love stick cars don't get me wrong. but the steel lenco with the steel planetary gears etc etc and bellhousing wow that's heavy and we haven't put the clutch in yet :o I had the chance to buy one in my early 30s it was a 4 speed with a reverser and wow it was heavy. I couldn't justify the cost to weight,
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I don't think you really need a Lenco or Liberty to handle that power. There are cars with T56's going 7's and they are much more easily streetable.
I would forget about automatics, they are just no good. As you've found out the torque pervertor is a power sapping deal that wastes a bunch of RPM. The Powerglide is a terrible street tranny and it's awful high first gear requires a very high stall speed with attendant slippage.
It also kills the launch and traction. Watching your runs on the live feed it leaves more like a school bus than a drag car. I think that is a couple tenths right there. A much higher stall speed will help but then you will be doing 5000 on the highway with tranny temperatures pegging the gauge.
The stick would be faster, get better mileage and more fun to drive. It can also be push started so no need to change the starter in the rain in a Piggly Wiggly parking lot.
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I don't think you really need a Lenco or Liberty to handle that power. There are cars with T56's going 7's and they are much more easily streetable.
C'mon Tom, a T-56 is not going to handle the 830 ft-pounds of torque delivered by my engine. The Magnums will handle 700 ft-lbs, but not reliably with slicks and side-stepping the clutch. I'd like to see a reliable, streetable 7 second car with a T-56. Maybe not so much a car, but a go-cart?
You can put a T-56 in YOUR 8 second street car and see what happens ::)
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Although I'm in the auto trans camp for your situation, Jay, some of the modified TKO's and T-56's are not wimps. The REM polished and cryo treated TKO 600's are rated (and dyno tested) for 700 lb-ft of torque. I think it would be easy to add another 15% capacity to the T-56.
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And you think they would hold up in a drag application, when a G-Force and Jerico won't?
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I think it would. Look at all the GT500's, Vipers, etc. out there running very low ET's and making 1000+ hp. All those cars have the OEM version of that Mag T-56.
However, thinking about the cost and thinking about how consistent it would be, I still think you should stick with the slushbox.
A T-56 behind an FE takes a good bit of work just to get it to bolt up unless you're willing to go with all-hydraulic actuation. You're gonna be in at least $800 just for the bellhousing itself, as you take a Quicktime FE/T-56 bell and make it SFI approved. I don't necessarily know if a Soft-Lok or similar would work for you, you might have to go with a hipo twin disc. Either way, you're looking at $1200-$1300 at least there.
The trans would probably run $4000+. In a heavy drag racing application, I'd be tempted to face plate the gears or pro-shift them.
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http://www.astroperformance.com/advanced_search_result.php?manufacturers_id=29&categories_id=100&subcategories_id=293&inc_subcat=1&x=24&y=12
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Well, color me skeptical on that one, Brent. My guess is that those race transmissions are heavily modified, and I wouldn't know the first thing to do to get them to hold up. Pretty sure I'm sticking with the slip-n-slide at this point...
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I found a couple T56 trans rated at 1200hp/1000ftlbs. G-Force makes one and Rockland Standard Gear makes one called Tranzilla, Lol.
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Hmmmm.... I'll look at those. Thanks for the info.
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Pretty sure I'm sticking with the slip-n-slide at this point...
I knew this was an early April Fools joke! >:(
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Jay do you have a anti roll bar in the rear of the Shelby clone ?
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Jay try Joels on Joy in Micihgan. They do all the C4's for the Cobra jet race cars for Ford. The Mod motors with Blowers are putting out a 1000HP+.
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Jay do you have a anti roll bar in the rear of the Shelby clone ?
Yes I do, Jack. Its an adjustable anti-roll bar from S&W race cars.
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Jay try Joels on Joy in Micihgan. They do all the C4's for the Cobra jet race cars for Ford. The Mod motors with Blowers are putting out a 1000HP+.
Chris, Blair turned me on to Joel's transmissions a while back. I have one in my Mach 1. That is a 530", 850 HP engine and when I called Joel to talk about a C-4 for it, he didn't sound real confident that it would hold up over the long term, in my application (big cubic inches plus lots of street miles plus track time). So far it has done fine, but I don't have a whole lot of time on it at this point. In any case, though, based on what he said, I'm not sure I'd want to try one behind my SOHC.
In 2009 I had a brand new C-4 behind the 935 HP SOHC in my Galaxie, built by a local guy who is very good with race transmissions. It made it all the way through Drag Week that year, but gave up on my last pass (after I'd already made one good pass on the last day). Teardown showed that it was mostly junk at that point, and needed a complete overhaul with lots of part replacements. Maybe Joel's transmission would have done better, but based on prior experience I'm a little gun shy on the C-4 at this power level.
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I'm a stick guy at heart,way back in the mid 80's McLeod started doing adjustable clutchs for Stock Elem. My friend was on the list at McLeod so he got one (a few really) and we went testing,no data logging just ET and feel really. In 2 days we killed 3 disc's but we knocked something like 2ths off the 60ft time . So they work , the problem is,was back then, that was ONE track. Without a lot of Data and logging switching from track to track will take at least 1 pass as a base line,then another to see if you went the right way,then a third money pass (at least). At your class level with the other at track make ready do you have time for 3 passes? That of course assumes nothing HAS to be repaired.
Simple ,proven,seems to be the theme of Drag Week,except for the guy who redesigns a 50 year old basically one off NASCAR engine and drives it on the street 1200miles and races at 5 different tracks,FOR FUN.
Work with your converter guy and move to Texas for winter testing before you tear the car apart.