Single or Multi disk Stall? im lost...
Oct 22, 2016 | 08:54 AM
#21
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Back when my truck was still a street truck, I ran a triple disk that was build by Precision (Vigilantly). I did have Chris @ Circle D open it up one day for a slight adjustment but nothing significant.
You can clearly hear in the video below of me doing WOT lockup in 3rd gear at the track. On this particular pass, I had it lock up at 105 mph which was right at the 1/8 mile. Also, I did some roll racing with the truck and was locking the clutch in 3 and even in 4th gear when I was consistently fighting off Z06's on the highway. Through all of that I never hurt the converter or any hard parts in the trans (it was a level 4 4L80e trans that was built buy FLT back in the day when Vince was still there, but I did eventually burn up some of the internal trans clutch packs. Cost of racing.
You can clearly hear in the video below of me doing WOT lockup in 3rd gear at the track. On this particular pass, I had it lock up at 105 mph which was right at the 1/8 mile. Also, I did some roll racing with the truck and was locking the clutch in 3 and even in 4th gear when I was consistently fighting off Z06's on the highway. Through all of that I never hurt the converter or any hard parts in the trans (it was a level 4 4L80e trans that was built buy FLT back in the day when Vince was still there, but I did eventually burn up some of the internal trans clutch packs. Cost of racing.
Oct 23, 2016 | 02:38 AM
#22
Seems my link didn't work how about this. Sounds like 3 shifts but the last is just the converter being put on lock down.
http://vid622.photobucket.com/albums...ids/1007-1.mp4
http://vid622.photobucket.com/albums...ids/1007-1.mp4
Oct 23, 2016 | 05:23 PM
#23
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From: Kansas City
This is gonna sound dumb but how do you lock up a stall converter? From what some of u guys are saying it's something you you can choose to do or not do. Is it just hitting a certain rpm in a certain gear? Someone break it down Barney style for me please lol
Oct 23, 2016 | 11:54 PM
#24
2x, stall lock up for dummies please
Oct 24, 2016 | 02:13 AM
#25
There is a actually a clutch disk or three or five in the front of the converter housing. I'm no trans guy but I believe during normal operation the typical oil flow in the converter keeps the clutches disengaged. An electronic solenoid in the valve body is actuated by the ecm to stop a particular circuit of oil flow allowing the clutches to engage.
*Note* I could have it backwards where the solenoid actually opens to allow oil flow to lock. Either way, thats how it works.
On a typical non lockup style converter, a really tight one at the top of high gear can slip as little as 4-5 percent. Some combo's, like mine for example (procharger) like a little more slip as I need rpm to make power. Through some testing of my own, so far I think my truck runs best with somewhere around 8-10 percent although its best ever pass showed 4 percent through the trap.
On a lock up converter, it does exactly as implied and locks the **** up. 0 percent or it's on its way to being burned up. Turbo combos specifically can respond nicely to this as in some cases the extra load on the engine can help spool the turbo. I'm no nitrous guy but I believe those respond well to lock up too.
This is all tuneable in the ecm. You can lockup the converter any time you want and even keep it locked during the shift if so desired. The down side to this and the reason you don't see that many people doing it......this basically eliminates the converter to soak up some of the shock "power" from the motor and it can break hard parts in the transmission.
*Note* I could have it backwards where the solenoid actually opens to allow oil flow to lock. Either way, thats how it works.
On a typical non lockup style converter, a really tight one at the top of high gear can slip as little as 4-5 percent. Some combo's, like mine for example (procharger) like a little more slip as I need rpm to make power. Through some testing of my own, so far I think my truck runs best with somewhere around 8-10 percent although its best ever pass showed 4 percent through the trap.
On a lock up converter, it does exactly as implied and locks the **** up. 0 percent or it's on its way to being burned up. Turbo combos specifically can respond nicely to this as in some cases the extra load on the engine can help spool the turbo. I'm no nitrous guy but I believe those respond well to lock up too.
This is all tuneable in the ecm. You can lockup the converter any time you want and even keep it locked during the shift if so desired. The down side to this and the reason you don't see that many people doing it......this basically eliminates the converter to soak up some of the shock "power" from the motor and it can break hard parts in the transmission.
Oct 24, 2016 | 01:02 PM
#26
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Ohhh ok, I think I got it now. So to recap, as far a physical parts causing it to lock up there would be no real difference between a multi disc set to stall at one speed and a multi disc set to stall at a higher speed right? Cuz that percentage of slip that ur talking about (8-10) is set while tuning the ecm? So basically when I get my truck tuned if it likes 6% then I'll have 6% slippage at a certain rpm? Home I didn't butcher that too bad lol.
Oct 25, 2016 | 12:23 AM
#27
No, the percentage of slip is built into the converter. It is what it is and depends on things like fins/fin angles/stators and other **** I don't know about. However, you should note, that just because you buy a 3200 stall converter from Jegs doesn't mean that it is going to stall to 3200. The efficiency of the converter is directly related to how much power the motor makes. If your doing a pretty hardcore setup (mine for example) it may take the converter builder a try or two to get the stall (shift extension numbers) and up top slip numbers where they need to be.
For example, if you took the converter out of a 400 rwhp N/A truck that had a stall speed around 3400 rpm and put it in my truck, it would probably stall closer to 7000 rpm.
Matter of fact I have a good story to show this. Back when I was swapping converters trying to get it close, I'd take the belt off the blower and transbrake it with no 2 step to see where it would end up. The last converter I used, it would stall around 3000 without the belt on the blower. Once the blower was hooked back up, it would stall around 6400 rpm. At the time, my motor in N/A form made right at 600 horsepower on an engine dyno without the blower. Never dyno'd it with the blower but based on weight/mph it was probably somewhere a little North of 1000 at the tires.
For example, if you took the converter out of a 400 rwhp N/A truck that had a stall speed around 3400 rpm and put it in my truck, it would probably stall closer to 7000 rpm.
Matter of fact I have a good story to show this. Back when I was swapping converters trying to get it close, I'd take the belt off the blower and transbrake it with no 2 step to see where it would end up. The last converter I used, it would stall around 3000 without the belt on the blower. Once the blower was hooked back up, it would stall around 6400 rpm. At the time, my motor in N/A form made right at 600 horsepower on an engine dyno without the blower. Never dyno'd it with the blower but based on weight/mph it was probably somewhere a little North of 1000 at the tires.
Oct 25, 2016 | 09:17 AM
#29
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I'm guesstimating that after I'm done that I will be around the 5-550 mark, somewhere around there. I was planning on just going with like a 3200 stall. So that stall could potentially stall higher huh? Well **** me sideways, that sux lol
Oct 25, 2016 | 11:09 AM
#30
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Well, this is going to hurt.
You'll hear from time to time about a loose stall, or a tight stall. Each power adder likes a different stall.
You can have a tight 3200 stall and a loose 3200 stall. The difference is the slip% that is built into the converter. A loose 3200 will slip more, rev easier and is more suitable for turbo's and procharger's.
A tight 3200 will have less slip% built into it and will not slip near as much as a loose 3200 and is much more suitable for a pd blower.
Make sense, somewhat?
You'll hear from time to time about a loose stall, or a tight stall. Each power adder likes a different stall.
You can have a tight 3200 stall and a loose 3200 stall. The difference is the slip% that is built into the converter. A loose 3200 will slip more, rev easier and is more suitable for turbo's and procharger's.
A tight 3200 will have less slip% built into it and will not slip near as much as a loose 3200 and is much more suitable for a pd blower.
Make sense, somewhat?