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what is free-wheeling a TH400?

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Old 12-22-2004, 12:53 PM
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Default what is free-wheeling a TH400?

I saw this mentioned in a few TH400 posts?
Old 12-22-2004, 03:47 PM
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If you use a reverse valve body pattern, it will not have engine braking in manual 2nd gear. I am not sure about manual 1st gear. This is not desirable for street use, and it can be dangerous. It also does not use the vacuum modulator, which is hard on the front pump, sealing rings, and it can have very hard shifts. Stick with the forward pattern which offers engine braking. Use the Trans-Go Performance Shift kit. When setup properly it can give you smooth part throttle shifts and firm WOT shifts.
Old 12-22-2004, 06:38 PM
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I've used the transgo 1&2 kit and it's great for an automatic th400.
I now run a th400 with a turbo action reverse manual vb with no engine braking.
When I first set the trans up there was a guy on another site that burned up his intermediate sprag.
He would coast in first while going fast and apparently it allows the direct drum to free wheel so fast it slings the lube off the sprag. In stock form the band would clamp it and stop the drum.
Old 12-22-2004, 08:40 PM
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Default vb

Originally Posted by Pro Built Automatics
If you use a reverse valve body pattern, it will not have engine braking in manual 2nd gear. I am not sure about manual 1st gear. This is not desirable for street use, and it can be dangerous. It also does not use the vacuum modulator, which is hard on the front pump, sealing rings, and it can have very hard shifts. Stick with the forward pattern which offers engine braking. Use the Trans-Go Performance Shift kit. When setup properly it can give you smooth part throttle shifts and firm WOT shifts.
l make a rev. vb with compression braking. in fact l made one today. worked great on the dyno
Old 12-22-2004, 08:45 PM
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Kilgore...you make these for production? i need a new rmvb with a brake for my TH400...art carr products suck ***
Old 12-23-2004, 08:26 AM
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I just bought a TH400 with a reverse manual valve body. The car is street driven some, but mainly raced. Am I correct in understanding that as long as I don't coast in 2nd gear, I won't cause any damage to the tranny? If I come to a complete stop at lights in 3rd, and then shift to 1st, will I be alright?

Also, if I am cruising along at 35mph or so in 3rd, and want to pull it down to 2nd to pass or take off, I won't do the tranny any harm as long as I put it in 2nd and then put the power to it?? Just trying to understand exactly when the damage occurs. Thanks.
Old 12-23-2004, 08:46 AM
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Originally Posted by BLK02WS6
I just bought a TH400 with a reverse manual valve body. The car is street driven some, but mainly raced. Am I correct in understanding that as long as I don't coast in 2nd gear, I won't cause any damage to the tranny? If I come to a complete stop at lights in 3rd, and then shift to 1st, will I be alright?

Also, if I am cruising along at 35mph or so in 3rd, and want to pull it down to 2nd to pass or take off, I won't do the tranny any harm as long as I put it in 2nd and then put the power to it?? Just trying to understand exactly when the damage occurs. Thanks.
i too am lost on this as well..i have heard with teh reverse vb you dont want to "freewheel" the tranny..they say 1st and second have no engine braking so if you shift from third to second it will be like neutral..so how in the hell do you like you said downshift to 2nd if your racing someone or want to pull it down to pass..if its like neutral then it will go nowhere or what? if u have to wait till you shift it to give it power then that sucks *****.guess i am just totally missing something here.
Old 12-23-2004, 12:48 PM
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Default freewheeling

Originally Posted by redbandit98
i too am lost on this as well..i have heard with teh reverse vb you dont want to "freewheel" the tranny..they say 1st and second have no engine braking so if you shift from third to second it will be like neutral..so how in the hell do you like you said downshift to 2nd if your racing someone or want to pull it down to pass..if its like neutral then it will go nowhere or what? if u have to wait till you shift it to give it power then that sucks *****.guess i am just totally missing something here.
the turbo 400 and 350 have one-way clutches in first and second. that means if you down shift to second at, say 40mph, all you have to do is open the throttle until you lock the one way and off you go. the bands in the trans are for compression braking. the rear band is also for rev.
Old 12-24-2004, 06:40 AM
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Originally Posted by john kilgore
the turbo 400 and 350 have one-way clutches in first and second. that means if you down shift to second at, say 40mph, all you have to do is open the throttle until you lock the one way and off you go. the bands in the trans are for compression braking. the rear band is also for rev.
thanks man..i just read somewhere that if you were say driving along at 40 or whatever and downshifted from third to second while giving it hell the tranny ... just couldnt grasp the concept of a tranny getting messed up from downshifting..so you can downshift all you want even at wot as long as youre at a reasonable speed and no harm will be done..the damage would occur if you were going 120 and slid it into 1st or second without any throttle and therfore the "freewheel" effect..am i correct?
thanks man



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