Why is a non-lockup converter better ...

[ijames]

than a lockup converter run not locked up? Obviously if it's a lockup and the clutches can take it and you lock it up, you will have zero slip. But what about if you don't lock up the lockup converter? Will it perform the same as a nonlockup, or is there something about having the clutch in there taking up space that makes the lockup converer inferior to a true nonlockup? This is all assuming a 200-4R, and comparing say a CPT (true art carr) nonlockup to something like a one disc vigilante that can't be locked at wot. Inquiring minds want to know .

 

[PaCemkr86]

that was just the choice for back in the day, when they werent making badass locking converters that lasted.. like they are now a days

 

[bison]

A non lockup converter will be a lot lighter and work much more effectively than a non locked lock up converter. If your car is faster than 11.0 then you will usually be better off with an efficient non locking converter. Good non locking converters are typically at least $800 and some are as much as $1200.

 

[turbojimmy]

A non lockup converter will be a lot lighter and work much more effectively than a non locked lock up converter. If your car is faster than 11.0 then you will usually be better off with an efficient non locking converter. Good non locking converters are typically at least $800 and some are as much as $1200.

FWIW, a good lock-up can be just as much if not more expensive.

I understand the lighter argument, but I don't understand 'much more effectively'. What's more effective than a 100% lockup? Or does a lighter, non-LU converter couple more effectively all the time, negating the benefit of the lockup at 90+ MPH?

Is there any real benefit to a lockup converter for a non-DD car? I just drive my car around town, rarely on the highway and get to the track a few times a year. I put around 2k per year on the car. I'm a little frustrated, actually, with my non-locking lock up converters.

Jim

 

[ijames]

Jim, that's kind of why I asked the way I did, I've not heard of that many people with lockup converters that really do hold up locking at wot once you get to the low 11's and certainly not in the low 10's. There are converters that will do it, but the clutches wear pretty fast so to me it just doesn't seem to be worth the bother. So given that you won't be locking at wot anyway, I wondered if there really was a performance advantage to the true nonlockup compared to a lockup that you just don't lock. If you aren't going to lock at wot there isn't much of a price difference between the lockups and nonlockups. There is a weight difference, but I didn't know if there really was an efficiency difference or not.

 

[turbojimmy]

Jim, that's kind of why I asked the way I did, I've not heard of that many people with lockup converters that really do hold up locking at wot once you get to the low 11's and certainly not in the low 10's. There are converters that will do it, but the clutches wear pretty fast so to me it just doesn't seem to be worth the bother. So given that you won't be locking at wot anyway, I wondered if there really was a performance advantage to the true nonlockup compared to a lockup that you just don't lock. If you aren't going to lock at wot there isn't much of a price difference between the lockups and nonlockups. There is a weight difference, but I didn't know if there really was an efficiency difference or not.

I have a 5-disc Vigilante which was pretty expensive and is supposed to hold up to WOT locks. Someone posted in another thread I started that he's trapping 139 MPH with a 5-disc Vigilante locking at 90 MPH. My converter was installed last fall and has never held up under a WOT lock. It will lock solid around town (which is annoying at 35 MPH) but not at 90 MPH WOT. I'm still trying to sort it out. Since I've invested in the 5-disc I need to stick with it, but once the sting of the Vigilante's price tag wears off I may sell it in favor of a non-LU.

Not to threadjack, but I'd also be interested in what needs done to the trans in order to install a non-LU. Is the change permanent?

Jim

 

[Grumpy]

Carl we have 3 low/mid 9 sec cars here with Vig lock ups .. so far so good ... 2 are driven on the street (needed the lock up for gas mileage :biggrin: ) we have Bruce's 9/11 in Melissa's car but haven't locked it up at the track "yet"

 

[NJ Torque]

Both my GNs have nonlockup Art Carrs and love em! The cars get driven about 5k a year if not more.

 

[Limited87]

My personal thoughts are I dont think the Vigilante is worth the $1100 (1000+60 pump kit+shipping) bucks vs. real Art Car non-lock ups you can pick up relativley inexpensive. Unless you are real adement about keeping 26 inch tall tires on the car which the Vigilante will help you possibly stay with.

I have both converters in seperate cars. The extra 10 pounds of weight the Vigilante has plus the annoying rattle they all have some worse than others with the clutches inside, I just cant justy them over the AC for the money.

Performance wise they may be good for a tenth or two and of course some more mph. I feel as others do, they are little harder on the crank of the car with the added extra weight plus the huge load/drag it see's when the converter fully locks at 90mph.

turbojimmy there is a non-lock up valve that needs installed. Once it is installed it is set up for non-lock up converter and cant go the other way unless it is changed back. The valve runs like $40 bucks from most builders.

Just my 2 cents.

 

[GSX-PKV]

Maybe it depends on how you use the car. I launch my car at the strip by just brake torquing to "load up" the converter. I have a single disk Vigilante lockup converter and it works great on the strip, street and Interstate highways. My car has always had great MPH through the traps and I think the lockup converter really helps.

 

[bison]

FWIW, a good lock-up can be just as much if not more expensive.

I understand the lighter argument, but I don't understand 'much more effectively'. What's more effective than a 100% lockup? Or does a lighter, non-LU converter couple more effectively all the time, negating the benefit of the lockup at 90+ MPH?

Is there any real benefit to a lockup converter for a non-DD car? I just drive my car around town, rarely on the highway and get to the track a few times a year. I put around 2k per year on the car. I'm a little frustrated, actually, with my non-locking lock up converters.

Jim

A lockup meant to be locked up in a 700hp car is usually around $1200 not including the other internals that would not necessarily need to be replaced to prevent failure if a ratio changed occured while locked.

Much more effectively means just that. If your not locking a lockup to gain performance then you are spinning a much heavier less efficient converter that is built around being locked at WOT. Having a lock up unlocked will generate much more heat in the trans as only a small % of the oil will go through the cooling circuit. It will typically give up too much performance when unlocked. A good non locking converter will be very efficent. 5% or less slip if built correctly for the application. The converter will do a great job of holding the engine in the powerband where it can provide the most efficient power where a lockup could pull the engine down too much if the gearing isnt optimal. or its locked too early.

I have seen the effects of a really good non locking converter in a TSO car. PM me if you want sources.

I myself dont see the benefit of buying a lockup to gain fuel economy. Its a few mpg at most but costs $300 or more initially than your typical non locking converter and isnt as efficient as a 5 disc when locked which is yet more $ or a good non locking unit. The non lockers are much more forgiving when built correctly and they are not as hard on the trans internals either.

 

[Bent6]

One topic that hasn't been addressed is heat - a converter's worst enemy. A non-lockup converter will generate more heat due to the slippage. This is why all modern cars with AT have lockup converters. The advantage of a non-locking converter is the fact that it's lighter which makes the turbo spool a little faster. Today's modern non-locking converters are much efficeint than those from 7-8 years ago but they will cost you about 300-400 RPM (aka MPG) at cruise and will generate a good bit more heat. If you rarely drive your car any further than the local cruise-in or it's for strip only, then a non-lockup is the best way to go.

There is no reason to run a lockup converter if you aren't going to use it. There is no magic ET number where a non-locking converter has advantage over a lockup. A GOOD lockup converter can be just as good if not better than a non-lockup. My race car makes in excess of 1300hp and runs in the 7's with a LOCKUP converter. Granted, it is a race only unit capable of withstanding up to 2k HP but it is worth a good 2 tenths and 3-5mph or more. My point is, some would have you to believe lockups are for the street only and non-lockups are for the track but a good lockup unit such as the Vig can work on the track and work well.

I am in the process of building a street car that should make around 700hp and be good for deep 10s and I will be using a lockup converter. This car will mainly be a street car and may even be driven on short trips with occasional track action. While a non-lockup might give better all out track performance, the trade offs in heat generated aren't worth it to me in this application.

 

[PaCemkr86]

One topic that hasn't been addressed is heat - a converter's worst enemy. A non-lockup converter will generate more heat due to the slippage. This is why all modern cars with AT have lockup converters. The advantage of a non-locking converter is the fact that it's lighter which makes the turbo spool a little faster. Today's modern non-locking converters are much efficeint than those from 7-8 years ago but they will cost you about 300-400 RPM (aka MPG) at cruise and will generate a good bit more heat. If you rarely drive your car any further than the local cruise-in or it's for strip only, then a non-lockup is the best way to go.

There is no reason to run a lockup converter if you aren't going to use it. My race car makes in excess of 1300hp and runs in the 7's with a LOCKUP converter. Granted, it is a race only unit capable of withstanding up to 2k HP but it is worth a good 2 tenths and 3-5mph or more. My point is, some would have you to believe lockups are for the street only and non-lockups are for the track but a good lockup unit such as the Vig can work on the track and work well.

I am in the process of building a street car that should make around 700hp and be good for deep 10s and I will be using a lockup converter. This car will mainly be a street car and may even be driven on short trips with occasional track action. While a non-lockup might give better all out track performance, the trade offs in heat generated aren't worth it to me in this application.

i totally agree with you.. see my post at the top

 

[brian]

I wondered if there really was a performance advantage to the true nonlockup compared to a lockup that you just don't lock. If you aren't going to lock at wot there isn't much of a price difference between the lockups and nonlockups. There is a weight difference, but I didn't know if there really was an efficiency difference or not.

IMO, as well as a few other builders here...There is a performance advantage to be had in going non lock.
If you do not lock your lock up converter, you will see significantly more slippage than a n-l.

My personal car was over one tenth quicker in a 10.7 car, in the 1/4 with a CPT converter over a Vig. Not alot, but quicker none the less.
Another customer of mine, picked up nearly 3 tenths and 3 mph in a low 10 car. He also wasted the clutches in 2 seperate Vig multi disc converters before going n-l.

The trans does not need all the H.D. billet parts as mentioned earlier. As a builder, I wish every customer, street or strip used a non lock up.
The heat issue is not nearly what people think either. Just running a good cooler will be enough in most applications. I personally would rather have a non locker all day.

As a note on lock ups, you never get full coupling, or 100% lock up at WOT .In a customers car that was running at the Nat`s. Their lock up converter saw as much as 43% slippage during a run, and just before the traps would see 5% (locked up, which is very good) slippage as recorded on there BigStuff ecu.

 

[ijames]

Thanks for the input, guys. Basically I want the lockup for gas mileage since my car is 98% street driven, but I've seen a few too many people have issues like Jim (plus the trans and engine wear and tear, plus I'm a cheapskate on some things ) to be willing to pay the extra bux for a lockup converter that I can lock at wot. I just wanted to know if I was giving up a bunch of performance by using a lockup converter and not locking it, compared to a nonlockup. Sounds like I'm carrying some extra converter weight and giving up some efficiency but not a huge amount, and I guess I'm willing to give up .1 or .2 seconds to get the gas mileage. Only real issue is the lack of fluid cooling not locked up but that would only be for a few seconds a pass anyway, from 90 mph on up, and that just doesn't seem to me to be that big a problem (and Brian seems to agree).

 

[TurboDave]

IMO, as well as a few other builders here...There is a performance advantage to be had in going non lock.
If you do not lock your lock up converter, you will see significantly more slippage than a n-l.

My personal car was over one tenth quicker in a 10.7 car, in the 1/4 with a CPT converter over a Vig. Not alot, but quicker none the less.
Another customer of mine, picked up nearly 3 tenths and 3 mph in a low 10 car. He also wasted the clutches in 2 seperate Vig multi disc converters before going n-l.

The trans does not need all the H.D. billet parts as mentioned earlier. As a builder, I wish every customer, street or strip used a non lock up.
The heat issue is not nearly what people think either. Just running a good cooler will be enough in most applications. I personally would rather have a non locker all day.

As a note on lock ups, you never get full coupling, or 100% lock up at WOT .In a customers car that was running at the Nat`s. Their lock up converter saw as much as 43% slippage during a run, and just before the traps would see 5% (locked up, which is very good) slippage as recorded on there BigStuff ecu.

Can I respectfully take exception to a couple of points?
First, I find it amazing that a 10 second car would waste a multi disc vig.!! I've been pounding the snot out of mine for well over 8 years now, and it still performs as well as it did the day it was new. Granted, I don't run a 10 second car, but still pound it pretty good with a mid/high 11 second machine.

As for not needing billet parts. I disagree, to a point. Once into the very low 12's or firmly into the 11's, there are one or two billet parts that are needed to negate the breakage that IS going to occur. The intermediate drum's input shaft in particular. It was the only way I was able to COMPLETELY stop my twice annual breakage. That and the planetary carrier.

I also find it strange that there are multi disc converters suffering "43%" slippage!! Or were you referring to singel disc units? If so, that I can believe.

Now that my regular heavy duty racing days are over, I certainly understand that I no longer need the strength of my multi disc Vig. but I certainly also WOULD NEVER run it as a daily driver on a non lock up converter. That makes no sense what-so-ever.

 

[bison]

IMO, as well as a few other builders here...There is a performance advantage to be had in going non lock.
If you do not lock your lock up converter, you will see significantly more slippage than a n-l.

My personal car was over one tenth quicker in a 10.7 car, in the 1/4 with a CPT converter over a Vig. Not alot, but quicker none the less.
Another customer of mine, picked up nearly 3 tenths and 3 mph in a low 10 car. He also wasted the clutches in 2 seperate Vig multi disc converters before going n-l.

The trans does not need all the H.D. billet parts as mentioned earlier. As a builder, I wish every customer, street or strip used a non lock up.
The heat issue is not nearly what people think either. Just running a good cooler will be enough in most applications. I personally would rather have a non locker all day.

As a note on lock ups, you never get full coupling, or 100% lock up at WOT .In a customers car that was running at the Nat`s. Their lock up converter saw as much as 43% slippage during a run, and just before the traps would see 5% (locked up, which is very good) slippage as recorded on there BigStuff ecu.

I agree with nearly all of this unless the trans is shifted while locked. In that case the trans will need billet internals or breakage will more than likely occur at the input, planet, or sun gear in the front of the trans. A non locker can definitely go a lot further without billet internals. I also agree that non lockers are the best way to go these days coupled with a good external cooler for the reasons you stated. They are just way more efficient than they were 10 years ago and more more forgiving on the transmission. Ive seen under 5% slip with a PTC non lockup converter in a TSO car. Ive never seen a vig 5 disc slip that much up top. Usually its around 1% even in a heavy 9 second car. Could there have been a problem with the converter or the lockup circuit?

 

[turbojimmy]

I agree with nearly all of this unless the trans is shifted while locked. In that case the trans will need billet internals or breakage will more than likely occur at the input, planet, or sun gear in the front of the trans.

Just some more fuel for the fire: I sheared the front off my input drum leaving a stoplight (in a 'sprited' manner, on drag radials). I never let the car shift with the converter locked.

Jim

 

[Bent6]

Not a good idea to shift while locked up. I also agree to an extent that 100% full lockup may not be achieved at first on FAST HEAVY cars. On that converter with 43% slip - are you sure that was a lockup? Maybe the data was wrong. I also agree that with a good cooler, a non-locker will be OK but if you ever roll on the highway for any distance, a lockup is worth it's weight (no pun intended).

 

[TurboDave]

As I eluded to (I think) I never let it shift while locked either. All of my breakage occured with the stock converter of all things.