Big Stall Time

John Robinson said:
With a lock up why would you want a tight converter? Tight converters hurt more parts......
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The tighter the converter the less difference there is between lockup and fluid coupling, so there will be less of a shock on driveline parts and the engine whenever it locks. However like Forrest stated earlier, I would say that locked shifts are probably more of a shock to the drivetrain than anything.
 
Josh:

What is the stall on the V10/V10 compared to the V10/Diesel?

I've got the 15 blade left cut and it's just a bit too tight with a 66/71/16. Not sure how a looser converter would drive and plow snow this winter. I suppose go through more clutch packs.

Paul
 
Iv'e broken a billet input and a stock intermediate shaft with a real loose converter and locked up shifts. I like them as tight as we can get them and still light the charger(s) good. With my old v10 stator converter I had before, I could floor it right when it hit 3rd gear and have easy 60+psi and lock it up manually and the dramatic drop in RPMs it would spin the tires on dry assphalt.
 
I think its best to get the tightest converter you can with reasonable spool. At least for a street truck.

Eric
 
Went with a stock stall, it's two steps looser from where i'm at now and should have a nice medium between lighting the charger and still putting some power down in fluid coupling.
 
John Robinson said:
With a lock up why would you want a tight converter? Tight converters hurt more parts......
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I think there's a case for this and also that lock up hurts parts. In my case building boost against the trans for 18 seconds or so isn't good for any thing in the drive train i'm sure. Further, the 60' is all in fluid coupling, the tighter the converter is the harder that 60' is on the driveline I'd think.
 
NickTF said:
I think there's a case for this and also that lock up hurts parts. In my case building boost against the trans for 18 seconds or so isn't good for any thing in the drive train i'm sure. Further, the 60' is all in fluid coupling, the tighter the converter is the harder that 60' is on the driveline I'd think.
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I could see both logics, but the "tighter" the converter, the easier it is on parts. Less slipping, less heat. Like releasing a clutch and accelerating in gear vs. slipping it then full release at a higher, more power making rpm. Lowering stall and increasing fluid coupling efficiency is a good thing. But I do agree with the previous post stating as much stall as your turbo/gearing needs. I'm only running a Wicked 62 and a 1500 stall triple from PTC. Working great, but when I upgrade the turbo, I will have them give me a little less fin angle for a higher stall speed. I could not see a reason to go over a 1900-2000 stall for a cummins that is driven on a regular basis.
(Redonkulous sized turbos excluded)
 
Mine's a v10/v10 modified. However, I'm a very special case- very light, manual VB, full line pressure all the time, 71/74/.9 and unported head. When I go to lockup I lose 150rpm at WOT. If the engine is lugging <2000rpm, it's ~200rpm.
 
joefarmer said:
Mine's a v10/v10 modified. However, I'm a very special case- very light, manual VB, full line pressure all the time, 71/74/.9 and unported head. When I go to lockup I lose 150rpm at WOT. If the engine is lugging <2000rpm, it's ~200rpm.
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From what we've seen on the stall on Brandon's truck, and also on the little D100, light weight REALLY seems to make the converter seem tighter...the factory 1st gen converter in the D100 seems awful tight compared to the other 1st gens I've been in.

Chris
 
Signature600 said:
From what we've seen on the stall on Brandon's truck, and also on the little D100, light weight REALLY seems to make the converter seem tighter...the factory 1st gen converter in the D100 seems awful tight compared to the other 1st gens I've been in.

Chris
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That all makes perfect sense. I would expect a lighter vehicle to make the converter seem tighter. It's all about load after all. Light vehicle huge tq or heavy vehicle less tq (generally speaking) it's all the same. With my 4x4 tank (compared to an s10 or other 1/2 ton conversions) I should be able to get the stall speed i need. With my current converter it's right on the ragged edge. Two steps up and I should be good hopefully even for more compressor in the future should I decide to do that:ft:
 
NickTF said:
That all makes perfect sense. I would expect a lighter vehicle to make the converter seem tighter. It's all about load after all. Light vehicle huge tq or heavy vehicle less tq (generally speaking) it's all the same. With my 4x4 tank (compared to an s10 or other 1/2 ton conversions) I should be able to get the stall speed i need. With my current converter it's right on the ragged edge. Two steps up and I should be good hopefully even for more compressor in the future should I decide to do that:ft:
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Correct...that why I was throwing it out there;)

Chris
 
Brake stall on a stock V10 converter is spec'd right at 2500RPM - that's where it was before I had the tranny built on my '98.

New diesel-spec converter has a fairly high stall (been almost 5 years can't remember) built to tighter tolerances for good efficiency - revs like it's in neutral half the time but still gets 11/14mpg on 10K lb. truck.

Wish I had that converter in the drag truck! :doh:
 
does anyone know the factory stall rpm in a commonrail? i am running a suncoast 91% convertor and all i have been told is that it is tighter than stock. i would like to know what the rpm stall for that convertor is as well as the factory. i think i need to get a loser convertor. driving on the street, pulling a trailer and racing it does wonderful but sled pulling i really need to leave the line around 15-20# boost and the brakes wont hold the truck past about 5-8 and i am breaking front driveshafts. i know the truck is making some decent power but i do believe this is a lot of the reason i am having trouble with breaking stuff. if i had a loser convertor that would let me build boost to 15# before it wants to lockup and move that would be great. i can get the other convertor suncoast offers but all i can get out of anyone is it is looser than stock and talking to suncoast all they said it is for big turbo applications. it would spool better in low but be terrible on the street and for racing plus be a lot harder on transmission internals especially the input shaft. any info or help on the subject would be greatly appriciated. thanks
 
SMOKIN-U said:
does anyone know the factory stall rpm in a commonrail? i am running a suncoast 91% convertor and all i have been told is that it is tighter than stock. i would like to know what the rpm stall for that convertor is as well as the factory. i think i need to get a loser convertor. driving on the street, pulling a trailer and racing it does wonderful but sled pulling i really need to leave the line around 15-20# boost and the brakes wont hold the truck past about 5-8 and i am breaking front driveshafts. i know the truck is making some decent power but i do believe this is a lot of the reason i am having trouble with breaking stuff. if i had a loser convertor that would let me build boost to 15# before it wants to lockup and move that would be great. i can get the other convertor suncoast offers but all i can get out of anyone is it is looser than stock and talking to suncoast all they said it is for big turbo applications. it would spool better in low but be terrible on the street and for racing plus be a lot harder on transmission internals especially the input shaft. any info or help on the subject would be greatly appriciated. thanks
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How often do you sled pull and how often do you tow heavy?
 
tow very rarely heck i drive the truck almost daily and tow every once and a great while. when i can keep the truck together i will try to hit at least one pull a week. i have learned to drive around my charger its not that bad at all. i just want something that will perform better on the track with out breaking crap!
 
Cummins Driver said:
I think stock stall would do you just fine.

The thing with going to loose is that you lose a lot of efficiency that is nice to have when daily driving. Especially if you pull a trailer. But if you dont, then i think a stock stall should be a pretty good stall for your setup.

Im willing to bet a stock stall converter will run up to 2100-2200rpm without a lot of problem in 4hi. 4 low is makes it much harder to hold back because of the gear reduction so a looser stall is needed if you need that RPM in 4 low(for sled pulling).

If the stock stall converters in these things were 1400-1600rpm, then the stock tranny would actually be alright!

And the looser of a converter you have, the harder it will be on shafts and parts when it locks. It has to make up more RPM difference to lock than a tighter converter so it shock loads the driveline harder. Probably not enough to hurt much, but it will be a little harder on stuff IMO.

Eric
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You hit the nail on the head on that one. I have a truck that's strictly for DD and towing with a VERY loose converter on it, the hard lock up broke the input shaft the other day and now I'm without a truck. Towing with it is HORRIBLE when compared to the 5 speed in the 12 valve because there's so much slipping, anything passed 2/3 throttle when the converter isn't locked brings the engine to about red line when towing but it feels like I'm hardly moving.:bang Once the converter locks though it's nice and fast but the lock up is extremely hard and rattles your teeth out.

I can see how a loose converter would be good for a big laggy turbo or if you are racing it but as a daily driver that tows then it's a lot better to have a nice tight converter.
 
I have an adjustable potentiometer on the dash which I will use to dial in exactly where overdrive comes in and then lock up occurs. That should save me some headache. This has turned in to a useful thread:Cheer:
 
Stall is so dependent on the truck. I believe the %ratings came from DTT years ago, and they would test them on Bill's truck, and determine the %. I am thinking the from the DTT days a stock one would be around 87% or so.

Back to the stall I ran a 10 bladed stator from Goerend, it was great on the street, and great with a sledpuller 68/65/14. Jump to the 66/71/14 or the 66/74/14 and it was still great on the street, but not very good at the sled. I could still get it to about 2200 under full boost. I stick a scheid lighting on it, and I could not get it lit at the sled. It would go to 1400 and stop. Several have mentioned it is charger dependent.

I would say a v10/v10 has about a 1700 no boost stall, but under boost I could probably hit 3000 if I wanted.
 
I know my converter only flashes to about 1200rpm under no boost. Then it has to build boost from there, and once it lights, it pulls real hard. It just wouldnt be too fun with a bigger charger.

Eric
 
Goin to be swapping in the new stock stall speed converter from Goerend this weekend. I hear the crossmember is fun ha! I'll report back on how it goes, thinking it should really make this charger alot more fun to drive and race!!!:ft:
 
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