Holy converter slip batman

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Toluene56

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I guess 20% slippage on the big end is a bit much. Time for some hygard, maybe it will tighten it up some till I can get another one.
 
I tried it and the only difference I noticed was my wallet was lighter.
 
I have heard of building one with a higher number but using the slip to multiply torque up there. I know of one guy that tried it out, but it was unusable for what he was doing.
 
I tried it and the only difference I noticed was my wallet was lighter.
I dont expect anything, my fluid is due for change.. smells a little cooked. So I figured might as well.. cheaper than buying atf at the auto parts store.
 
I dont expect anything, my fluid is due for change.. smells a little cooked. So I figured might as well.. cheaper than buying atf at the auto parts store.



I went from using Dextron 3 in my powerglide to type F because of the smell. Some of that Dextron was smelling burnt right out of the bottle.
 
I went from using Dextron 3 in my powerglide to type F because of the smell. Some of that Dextron was smelling burnt right out of the bottle.
I think I have the b&m stuff in it. The fluid is blue.. smells God awful. But it's gotten pretty dark as well. I remember is smelled horrible brand new too.
 
I think I have the b&m stuff in it. The fluid is blue.. smells God awful. But it's gotten pretty dark as well. I remember is smelled horrible brand new too.



i may be mistaken but I’ve been told B&M fluid is type F with blue dye added. And 5.00 more a quart charged.
 
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Have always run Tractor Supply hydraulic fluid in my 727. It's what was recommended by the tranny builder. Tore it apart after 4 years of racing and the friction surfaces looked like they had about 100 miles on them. Only thing is it makes it a little hard to read on the dipstick.
 
i may be mistaken but I’ve been told B&M fluid is type F with blue dye added. And 5.00 more a quart charged.
I can believe it. Trans might be due for a refresh this winter... the fluid was pretty cooked.
 
Must be that blower is giving things down stream of the crank a bit of a workout.

Maybe some of that observed 20% “converter slip” is the high gear clutch pack slipping a bit.
 
Must be that blower is giving things down stream of the crank a bit of a workout.

Maybe some of that observed 20% “converter slip” is the high gear clutch pack slipping a bit.
I'm sure that's happening a bit too.
 
What's normal for slippage?
From what I've been reading over the interwebs, I see different amounts

Full boar mama Jama race car - (-)0-3%
Race car but not so mama jama - 0-5%
Sometimes race car Sometimes not - 5-10%
Usually when there is more than 10% all the race car people aren't happy. This is what I found in my wanderings.
 
From what I've been reading over the interwebs, I see different amounts

Full boar mama Jama race car - (-)0-3%
Race car but not so mama jama - 0-5%
Sometimes race car Sometimes not - 5-10%
Usually when there is more than 10% all the race car people aren't happy. This is what I found in my wanderings.
Okay cool, thank you for that info.
When I get my engine off the Dyno that will help me decide on a ring and pinion. I'm thinking I'll be looking at the not so mama-jama race car number.
Low 10s big block stroker
 
I don't know about converter slip % but, my cheep 3000 stall converter, when through the traps at 6000 rpm.
My high dollar 4200 stall converter, when through the traps at 5700 rpm. and picked up almost 2 mph nothing changed but the converter!
 
I don't know about converter slip % but, my cheep 3000 stall converter, when through the traps at 6000 rpm.
My high dollar 4200 stall converter, when through the traps at 5700 rpm. and picked up almost 2 mph nothing changed but the converter!

With 4.30s and 28" tires, the calculated 6000rpm is 116mph, which is what your tach would/should show if you had a clutch, which would be zero% slip.
If your 3000TC trapped at 108, that would be 108/116=.931 or ~6.9% slip.
If your 4200TC gained 2mph, say 110, that would be 110/116 =.948, or 5.2%
Fun with math
EDIT
If your powerpeak is at 5400, then 6000 is somewhat off the pipe; and 5700 is more like it. The 4200 is also converting less power into heat, leaving more power to gain speed, which should translate to a slightly quicker ET.
 
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4.56s 26" slicks at the time of converter change
Also 1/8 mile trap/ track.
 
5600 esh with my now 28" tires and 4.56 gears.
would like to go back to my 26" slick, now that i have learn a thing or two, about making this thing hook better. or step up to 4.88 with my 28" slicks.
but that take money i don't have so i live with what i got.
 
Had exactly the same happen with a friend of mine, '70 challenger, 555hp 440 motor on the day, weight around 3800lbs all in, changed converter from a hughes 3500 stall to a used 10" TCI super street fighter, approx 4000+stall in his car however in the traps he's pulling 6700rpm+ and hitting the limiter and its still pulling he says, 727 was just rebuilt with all new clutches etc.

I worked out that 11.06@121 in 3800lbs with 3.73's/28" slicks/555hp should be around 5427+slip, 6700 is around 20% slip...wtf, got me on that one. If he's blowing through the converter why is it still pulling as he says and it ran its best mph and ET as well but thats cos his ran his best 60 as well.
 
Had exactly the same happen with a friend of mine, '70 challenger, 555hp 440 motor on the day, weight around 3800lbs all in, changed converter from a hughes 3500 stall to a used 10" TCI super street fighter, approx 4000+stall in his car however in the traps he's pulling 6700rpm+ and hitting the limiter and its still pulling he says, 727 was just rebuilt with all new clutches etc.

I worked out that 11.06@121 in 3800lbs with 3.73's/28" slicks/555hp should be around 5427+slip, 6700 is around 20% slip...wtf, got me on that one. If he's blowing through the converter why is it still pulling as he says and it ran its best mph and ET as well but thats cos his ran his best 60 as well.
Mine is still pulling as well.. its not completely blowing through the converter, but 20% is a lot.
 
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