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Discussion Starter #1
Recently added a reverse manual valve body to my C4 and wondering if it's possible to shift past 3rd gear and lock-up trans momentarily and strip the splines in the converter. 2 weeks ago during an 1/8th mile pass my car felt like I shifted to neutral on a 2 -3 shift. Had no reverse or drive gears and was towed back to the pits. Pulled trans and converter spline was stripped and input shaft was basically ok. My car runs 7.50's in the 1/8 and don't think my power level contributed to damage.
 

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Just a bad convertor. Get a heavier made one.
 

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Discussion Starter #3
I don't know how factual it is but I've heard that pulling past 3rd gear on a reverse pattern valvebody it goes into reverse. I see how this could strip your splines or break an input shaft.
 

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Neutral comes before reverse.

Splines strip out.
 

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Discussion Starter #5
Just to clarify, It's a reverse shift pattern - PRN123. What happens in valvebody if it is pulled past 3rd detent????
 

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I agree with Stuart. Bad converter!
 

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Discussion Starter #8
Lets think out of the box here. A valve body controls shift by a stepped plunger opening and closing different passageways to divert fluid to the appropriate clutch packs and servos. Now if you push that plunger further in the bore you can change the path of fluid to an undesired component. I think it also depends on how the manufacturer modified the OE design of the body to make it a manual shift.
 

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Pretty sure reverse pattern valve bodies are custom made that way.

It may be the converter or might be a transmission problem. I snapped 2 input shafts with a sloppy 2nd to 3rd shift in the valve body but that was before I went to a manual shift valve body. It goes to neutral between gears momentarily and if you are running something with some power a bad thing happens when it finally hits 3rd. If your shifter is not aligned to the transmission detents just exactly right that might contribute to this problem.

If that stuff is under warranty the builder should make good on it.
 

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Discussion Starter #10
Converter was 6 yrs old(mostly street driving) and supplier has recently repaired and increased stall for $89. I have freshened trans and installed a hardened input shaft. Went to the track last saturday and ran great. Picked up 2 tenths and 60' went from 1.7x to a 1.61.
 
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