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Re: 727 and burnouts
[Re: Tempest]
#1960205
11/30/15 01:29 PM
11/30/15 01:29 PM
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Joined: Jun 2008
Posts: 10,847
Oakdale CT
gdonovan
I Live Here
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I Live Here
Joined: Jun 2008
Posts: 10,847
Oakdale CT
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Just to reiterate, I'm talking about street driving, not track and heating tires. The trans is a built 727 with a MVB. Its been my IMPRESSION this is more of a problem with slicks since it is the shock of the slicks suddenly stopping the drivetrain motion that damages the sprag assembly. It could be a problem on the street with sticky drag radials. Average street tires are too slippery for the drivetrain shocking. That being said; I still make sure I'm not in first when letting off the loud pedal on the street out of habit.
"I think its got a hemi"
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Re: 727 and burnouts
[Re: Tempest]
#1960760
12/01/15 07:15 AM
12/01/15 07:15 AM
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Joined: Dec 2010
Posts: 208
Norrland, Sweden
Swedcharger67
enthusiast
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enthusiast
Joined: Dec 2010
Posts: 208
Norrland, Sweden
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This is the way I understand the function of the 727.
You have 2 scenarios:
1. Gear shifter is in manual low (L)
2. Gear shifter is in D, first/low gear is active.
In case 1 the low band apply protects/locks the sprag, while in case 2 the sprag is active (no low band apply).
I believe the danger in case 2 is that while doing a burn out in low gear (shifter in D) a slight disturbance in the engine (like hitting the rev limit, misfire, fuel problem, or pedal the throttle) will/may cause the sprag to start free wheeling...and now a moment later when/if the full engine power is restored, the sprag will, with full power, slam back into locked position, and this causes a huge load on the sprag, and may destroy it.
So, never a burnout with the shifter in the D-position. A burnout in manual low (L) is a lot safer, if I understand things correctly.
Martin, 67 Charger, 512 cui, E85, MegaSquirt MS3X sequential ignition & injection
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Re: 727 and burnouts
[Re: Swedcharger67]
#1960790
12/01/15 10:29 AM
12/01/15 10:29 AM
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Joined: Nov 2013
Posts: 595
Nashville, Tennessee
Tempest
OP
mopar
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OP
mopar
Joined: Nov 2013
Posts: 595
Nashville, Tennessee
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This is the way I understand the function of the 727.
You have 2 scenarios:
1. Gear shifter is in manual low (L)
2. Gear shifter is in D, first/low gear is active.
In case 1 the low band apply protects/locks the sprag, while in case 2 the sprag is active (no low band apply).
I believe the danger in case 2 is that while doing a burn out in low gear (shifter in D) a slight disturbance in the engine (like hitting the rev limit, misfire, fuel problem, or pedal the throttle) will/may cause the sprag to start free wheeling...and now a moment later when/if the full engine power is restored, the sprag will, with full power, slam back into locked position, and this causes a huge load on the sprag, and may destroy it.
So, never a burnout with the shifter in the D-position. A burnout in manual low (L) is a lot safer, if I understand things correctly. The question was regarding a reverse manual valve body trans.
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Re: 727 and burnouts
[Re: Tempest]
#1960795
12/01/15 10:48 AM
12/01/15 10:48 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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The question was regarding a reverse manual valve body trans. [/quote] You start in second or high gear... heavy car.. start in second... my car is light so I start out in high gear... speed of the tire is what your after to heat it up 
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Re: 727 and burnouts
[Re: Tempest]
#1961076
12/01/15 04:59 PM
12/01/15 04:59 PM
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Joined: Jan 2003
Posts: 25,728
Rio Linda, CA
John_Kunkel
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 25,728
Rio Linda, CA
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Just to reiterate, I'm talking about street driving, not track and heating tires. The trans is a built 727 with a MVB. LBA or no? Since most street burnouts don't involve a water box, trying to start a burnout in 2nd (depending on tires) will be a non-starter (pun intended) so you're stuck starting in 1st. If no LBA, you're laying with fire.
The INTERNET, the MISinformation superhighway
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Re: 727 and burnouts
[Re: John_Kunkel]
#1961117
12/01/15 06:18 PM
12/01/15 06:18 PM
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Joined: Nov 2013
Posts: 595
Nashville, Tennessee
Tempest
OP
mopar
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OP
mopar
Joined: Nov 2013
Posts: 595
Nashville, Tennessee
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Just to reiterate, I'm talking about street driving, not track and heating tires. The trans is a built 727 with a MVB. LBA or no? Since most street burnouts don't involve a water box, trying to start a burnout in 2nd (depending on tires) will be a non-starter (pun intended) so you're stuck starting in 1st. If no LBA, you're laying with fire. Not sure on the LBA? I did not have the trans built. The car has a line lock and enough HP to kill the tires in 2nd, so I guess I will just have my fun in 2nd from now on. I'm still just wondering how we did all those street burnouts back in the day with 727's never having issues. I will do them in 2nd from now on. I like my feet!
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Re: 727 and burnouts
[Re: Tempest]
#1961138
12/01/15 06:51 PM
12/01/15 06:51 PM
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Joined: Dec 2010
Posts: 208
Norrland, Sweden
Swedcharger67
enthusiast
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enthusiast
Joined: Dec 2010
Posts: 208
Norrland, Sweden
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Maybe I'm missing the point in this discussion but even the standard 727 has LBA in manual low (L) as far as I understand.
Presumably a manual valve body has it too?
From my point of view it should be perfectly safe to start in manual low (L) and shift up when needed???
Martin, 67 Charger, 512 cui, E85, MegaSquirt MS3X sequential ignition & injection
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Re: 727 and burnouts
[Re: Swedcharger67]
#1961221
12/01/15 08:41 PM
12/01/15 08:41 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Maybe I'm missing the point in this discussion but even the standard 727 has LBA in manual low (L) as far as I understand.
Presumably a manual valve body has it too?
From my point of view it should be perfectly safe to start in manual low (L) and shift up when needed??? On the LBA .. he would have to figure out who made it and see if it it LBA... my old TA valve body is a RMVB with a trans brake... it is not a LBA.. the stock valve body is a LBA.. but you never know for fact on a aftermarket RMVB... he can test it... put it in low gear.. run up to 20 or so MPH and decell the engine... if its a LBA it will slow the car with the engine... if not LBA the car will just coast
Last edited by MR_P_BODY; 12/01/15 08:54 PM.
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Re: 727 and burnouts
[Re: Swedcharger67]
#1961286
12/01/15 10:14 PM
12/01/15 10:14 PM
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Joined: Jan 2003
Posts: 25,728
Rio Linda, CA
John_Kunkel
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 25,728
Rio Linda, CA
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Maybe I'm missing the point in this discussion but even the standard 727 has LBA in manual low (L) as far as I understand.
Presumably a manual valve body has it too? You presume wrong; I'll go out on a limb and opine that the majority of RMVB's don't have LBA. Easy to test, place the shifter in low, roll up to about 20 mph and throttle back to idle; if it has LBA the car will nose over under compression braking, if not, the car will just freewheel and coast with no braking effect.
The INTERNET, the MISinformation superhighway
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Re: 727 and burnouts
[Re: John_Kunkel]
#1961308
12/01/15 10:54 PM
12/01/15 10:54 PM
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Joined: Dec 2010
Posts: 208
Norrland, Sweden
Swedcharger67
enthusiast
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enthusiast
Joined: Dec 2010
Posts: 208
Norrland, Sweden
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I see, thanks for the good info.
It just seems very odd to me that the LBA-feature in the stock valve body would most likely be missing when investing in a RMVD. Maybe there is a technical reason for it...difficult oil routing in the VB, faster shifting, less drag or other?
Martin, 67 Charger, 512 cui, E85, MegaSquirt MS3X sequential ignition & injection
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Re: 727 and burnouts
[Re: John_Kunkel]
#1961333
12/01/15 11:29 PM
12/01/15 11:29 PM
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Joined: Jun 2008
Posts: 10,847
Oakdale CT
gdonovan
I Live Here
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I Live Here
Joined: Jun 2008
Posts: 10,847
Oakdale CT
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Maybe I'm missing the point in this discussion but even the standard 727 has LBA in manual low (L) as far as I understand.
Presumably a manual valve body has it too? You presume wrong; I'll go out on a limb and opine that the majority of RMVB's don't have LBA. Easy to test, place the shifter in low, roll up to about 20 mph and throttle back to idle; if it has LBA the car will nose over under compression braking, if not, the car will just freewheel and coast with no braking effect. My manual valve body which has been in the car for 25 years has no engine braking in first gear. Turbo Action unit.
"I think its got a hemi"
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Re: 727 and burnouts
[Re: Mr.Yuck]
#1961369
12/02/15 12:20 AM
12/02/15 12:20 AM
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Joined: Sep 2015
Posts: 1,096
Australia
ozymaxwedge
super stock
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super stock
Joined: Sep 2015
Posts: 1,096
Australia
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I typically start in 2nd then hit 3rd at 5k and roll out of it and up to the line. You tires will spin faster Exactly how to do it at the track or on the street  If you have the power to start in top well do it. I have belted piss out of my 727's without a failure, street, strip, slicks, radials, strokers, nitrous and wheelstanding 9's. I have killed convertors, diff centres and axels though. A car with a bit more HP may have a positive affect on trans as it have the wheels spinning with ease rather than struggling or labouring. Love burnouts. Is there a burnout thread ?
1963 Plymouth Max Wedge
1971 Barracuda
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Re: 727 and burnouts
[Re: Tempest]
#1961370
12/02/15 12:20 AM
12/02/15 12:20 AM
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Joined: Jan 2003
Posts: 8,018
Tulsa OK
Bad340fish
master
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master
Joined: Jan 2003
Posts: 8,018
Tulsa OK
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I always started my burnouts in first before I got a line lock, it never really free wheels against the brakes and I shift to 2nd quickly. It took me 20 years to finally put a line lock on my car and now that I have one I start my burnout in 2nd gear. This is with a turbo action non apply manual VP
68 Barracuda Formula S 340
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Re: 727 and burnouts
[Re: Tempest]
#1961376
12/02/15 12:24 AM
12/02/15 12:24 AM
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Joined: Sep 2015
Posts: 1,096
Australia
ozymaxwedge
super stock
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super stock
Joined: Sep 2015
Posts: 1,096
Australia
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Hey Tempest might be time to sweep the floor in there, it's looking a little untidy
1963 Plymouth Max Wedge
1971 Barracuda
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