TorqueFlite Burnouts

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D-50394 said:
It is a 727....
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I'd pull it down just for piece of mind. When I broke my 8 3/4 I pulled my 727, everything was good but it was worth the trouble to keep that little doubt out of my mind.
 
I run a full manual valve body in my 76 big block duster using a 727. Start burnouts in 3rd gear in the water box until smoke rolls off the tires, never had an issue. Safety first, scatter shields are worth it!
 
The problem with an automatic shift is that when the tranny shifts back to first on its own from second when the tires grab traction is the only thing holding the gear train is the sprag and it can only take so much abuse. U need to manually shift down to first b4 the tires get traction. Or just stay in first as the band will be applied while the shifter is in nanulal low. Kim
 
oldkimmer said:
The problem with an automatic shift is that when the tranny shifts back to first on its own from second when the tires grab traction is the only thing holding the gear train is the sprag and it can only take so much abuse. U need to manually shift down to first b4 the tires get traction. Or just stay in first as the band will be applied while the shifter is in nanulal low. Kim
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nanulal ???
edit: LOL!
 
The man I bought my 727 from a reputable builder told me to do everything in second. So when they signal me to come to the burnout box I am in second do my burnout in second. Pull up clean her out and drop in first and stage. No problems yet. 450 hp. small block going 11.0s Kevin.
 
I always start in 2nd and click it to 3rd, and that's with a 273, i am sure big blocks have the torque to do that.
 
so, here is a thought

i have an regular auto 727
it is the 1-2 shift that kills the sprag, correct?

why not just shift into 1st, and keep it there during the burn out?
 
No, it's the 2 back to 1 shift that kills the sprag when it shifts on its own. Shift it manually back to 1before it has a chance to on its own. Kim
 
diymirage said:
so, here is a thought

i have an regular auto 727
it is the 1-2 shift that kills the sprag, correct?

why not just shift into 1st, and keep it there during the burn out?
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hotrod360andy said:
Bolt in sprag anyone??
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I was told a bolt in sprag is just one that you put in a transmission that has spun the sprag in it and messed up the case. You can buy a good sprag that has more rollers.
 
Go back to post #2 and read. Over and over. That's ALL you need to do. You don't need a bolt in sprag. You don't need a manual valve body. You don't need anything special at all.

All you need to do is make SURE you are still spinning on the 1-2 shift. If you hook on the 1-2 shift, that's the possible problem.

Simply get the tires spinning in 1st in the bleach box, make the shift to 2nd in the box STILL SPINNING then come out still spinning and shift to 3. Real simple.
 
with my 340 and 10" slick i HAD to start in 1, not enough torque with a stock-esh converter.
Hit 6 grand shift to 2nt hit 6 grand shift to 3 and let it grab.
With my 408 i start out in 2n(because i can) shift to 3 and roll throttle back out to grab. same 727 and converter in both engs. when i rebuild it, it will get an alu drum, just for piece of mind... a bolt in sprag my not be a bad idea as well.
 
Cudafever said:
with my 340 and 10" slick i HAD to start in 1, not enough torque with a stock-esh converter.
Hit 6 grand shift to 2nt hit 6 grand shift to 3 and let it grab.
With my 408 i start out in 2n(because i can) shift to 3 and roll throttle back out to grab. same 727 and converter in both engs. when i rebuild it, it will get an alu drum, just for piece of mind... a bolt in sprag my not be a bad idea as well.
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I`m thinking about going manual, altho I hate to now that everything is working so well. It still has a harsher up shift to 3`rd if it`s not pulling hard tho.
 
Mind is also the no reverse band in first. Only the sprag to hold at the burn out/line.
#1 you can't get a better/ cleaner 1-2 shift.......you just can't!
#2 This 727 has been in my car for 20+ years now. fluid changed once a year, alway red.
But to be fair, any transmission built to hold up to 600 HP, will live a long time behind a 290 HP 340, and now 450 HP stroker.
Just remember, sprags fail under shock loads. even a transbrake transmission don't give a shock load to the sprag.....It is already lock up. So will disagree, but think about it. If my left foot is on the brake and right the gas........or trans brake is on and right foot is on the brake......the sprag is loaded and releasing the brake only lessend the load on the sprag not increase.(exception to this rule of course)
 
Here's the thing about this question. The real answer is you need to contact someone who builds these transmissions professionally and ask them. There are just to many variables to equate everyones experience to your transmission. Is it manyal shift? What if any shift kit is in it? Does it have a low band apply? A these ? Need to be answers to know.
 
My transmission was built by john cope, auto shift with low band apply. 727 was told to do burn out only in manual low. Have been doing that for 10 years with it. That being said I have a trans blanket on it.
 
One of the more memorable explosions:
KABOOM! This ‘Cuda’s Transmission Explosion Ventilated Just About Everything In The Car

cuda-xmsn-2.jpg
 
Killer6 said:
In manual low, the low/reverse band is holding the drum unless the valve body &/or separator plate are modified to block it's operation in low, coming out of first by manually
shifting to second releases the band then hits second gear.......the transition between gears "hits" the sprag like a neutral drop.
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I found that way interesting too. stock drum better have a rev limiter at below 6000.
aftermarket (steel not cast) 8000 rpm max.
All alu. 8800 rpm max.
These are all to distortion not fail, because if i'm going to spend big dollars on a part like this...........i want some fudge factor figured in.

my next rebuild will have one of these.....just can't decide on the all alu. or the steel.......
 
Cudafever said:
I found that way interesting too. stock drum better have a rev limiter at below 6000.
aftermarket (steel not cast) 8000 rpm max.
All alu. 8800 rpm max.
These are all to distortion not fail, because if i'm going to spend big dollars on a part like this...........i want some fudge factor figured in.

my next rebuild will have one of these.....just can't decide on the all alu. or the steel.......
Click to expand...
I do not recall who makes it, but there is an aluminum 727 drum on the market that has a steel sleeve on the outside so you do not get all the aluminum in the trans fluid and the associated maintenance.
I just wish someone would make one for the 904. But Tcs tells me it may be coming.
 
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