TH400 RBMVB Downshifting
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Teching In
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TH400 RPMVB Downshifting I just had my TH400 built with all Coan racing parts including Forward drum and supersprag and Transbrake but i dont understand the whole dont downshift and worse still the big writing on the transbrake instructions that say " Dont neutral or downshift transmission during shutdown – Leave in high gear only'....now that is all well and good but i have a Twin Turbo LS1 and i dont really fancy letting it idle in high gear for a minute or so before shutting down.....am i gonna stuff my trans?I like to be able to drop my car back into second gear and light the tyres at 70mph...did i stupidly buy race only components?...i would not ask this question on our Aussie LS1 forum...I need USA input
Last edited by nurse; Mar 28, 2007 at 07:15 AM.
Launching!
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when you downshift to a lower gear it launches the internal parts of the tranny into the stratosphere regarding RPM. You aren't going to do any damage to the rotating assembly letting it coast down. 
For a greater explanation call Mikes in Lancaster, CA. He built my Ultimate Vasco 400 that is on it's 6th season without a rebuild, he can explain it better.
For a greater explanation call Mikes in Lancaster, CA. He built my Ultimate Vasco 400 that is on it's 6th season without a rebuild, he can explain it better. I just come to a complete stop before I downshift but I would also like to know the rules on when I can and cant downshift.I have had all these dang bikes pullin up next to me lately and I wouldnt be able to do much in 3rd gear.
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Do not downshift during shutdown in meaning do not downshift after reaching a high speed. Downshifting at a high speed off the throttle may possibly cause you to lose control of your car and will possibly damage parts....A reverse shift pattern will require you to downshift to get to neutral...
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Originally Posted by modracr62
Do not downshift during shutdown in meaning do not downshift after reaching a high speed. Downshifting at a high speed off the throttle may possibly cause you to lose control of your car and will possibly damage parts....A reverse shift pattern will require you to downshift to get to neutral...
Thats why they always leave the front band out with a RMVB!
The front band gives it engine braking and makes the engine rev/wheels slow down when downshifted. A RMVB trans should not have engine braking.
Originally Posted by SuperZ
I just come to a complete stop before I downshift but I would also like to know the rules on when I can and cant downshift.I have had all these dang bikes pullin up next to me lately and I wouldnt be able to do much in 3rd gear.
You have to know your car well to be able to do this because mine will go sideways at 90+ when I do this.
Thread Starter
Teching In
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Wow guys thanks for the response..i have no engine braking btw...I think i will still down shift because i cant resist droping my car back to second and lighting them up when it is required...and that is often
What I have gotten from the whole debate is do not downshift after going through the traps at 1xx MPH.
I roll about 40 45 MPH and downshift to second and mash the throttle. I have not noticed any excessive wear doing this.
Carl Rossler built the tranny though and I could not tell you exactly what he does inside of em.
I roll about 40 45 MPH and downshift to second and mash the throttle. I have not noticed any excessive wear doing this.
Carl Rossler built the tranny though and I could not tell you exactly what he does inside of em.
BTW this is not the first, second, third, or even fourth time I've seen and/or been a part of discussing how to drive a RMVB th400 in this forum. Maybe search and find more opinions.
Problem is there are too many opinions. Driving a RMVB th400 is not like piloting the space shuttle. Well unless you're going like 200 mph and you downshift to coast and the direct drum explodes through the floorboard. I have a pic of that somewhere believe it or not.
Problem is there are too many opinions. Driving a RMVB th400 is not like piloting the space shuttle. Well unless you're going like 200 mph and you downshift to coast and the direct drum explodes through the floorboard. I have a pic of that somewhere believe it or not.
