fmx to c6 conversion

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scvol

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I am attempting to convert my fmx to c6 transmission and am having some shift linkage issues. Does anyone know if there is a kit for the c6 trans to fit the original linkage or if the is a good way to get around this. I am to the point of either trying to fabricate a bracket to fit or possibly pulling the linkage off the fmx and seeing if it will fit on the c6 which will basically require two trans. rebuilds. I have already shortened my driveshaft and bought a new crossmember mount and ready to fire this baby up but have hit a slight snag and looking for some direction.

 

OMS

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I am attempting to convert my fmx to c6 transmission and am having some shift linkage issues. Does anyone know if there is a kit for the c6 trans to fit the original linkage or if the is a good way to get around this. I am to the point of either trying to fabricate a bracket to fit or possibly pulling the linkage off the fmx and seeing if it will fit on the c6 which will basically require two trans. rebuilds. I have already shortened my driveshaft and bought a new crossmember mount and ready to fire this baby up but have hit a slight snag and looking for some direction.
Are you looking for the trans to shifter linkage?

OR

The linkage to change column shift to floor shift?

 

scvol

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shifter to trans, kick down linkage to trans, and park safety linkage to trans. (not even sure if a c6 has the park safety set up). I have all the linkage other than where it hooks up to the transmission. I wish the bracket on the fmx would come off without dissasembling the whole trans. but I think that is the only way it will come off.

 

72HCODE

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well the correct C6 linkage would require the entire transmission to come apart as well. :(

I learned about it the same way, a random C6 was installed in my car so i found out the correct shifting linkage would be quite an effort to install.

the kickdown lever is a bolt on so that would be easy.

but if you want the correct linkage on the transmission so you can use the Transmission lockout then you have to take the entire trans apart to get to the sleeve to change out the system from another c6.

The shifter to the C6 is easy to change the FMX is curved and the C6 is basically straight that is a bolt on.

i had ti change mine as well. But i left the FMX shifter with the Neutral safety switch attached and working. i never liked the C6 neutral safety attached to the trans housing exposed to the elements.

 

whisnane

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The shifter linkage will nor interchange from a FMX to a C-6.You have to remove the valve body on both to change or replace the shifter linkage. C-6 trannys have a floor shift linkage and a column shift linkage.Find out which you have .Whisnane

 

scvol

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It is a floor shift. I got the shift and kickdown linkage on today with a few minor mods. I just have to figure out what to do with the linkage that hooked up from the steering column to old fmx that kept you from putting the vehicle in gear without turning key on. I may just remove it if the C6 has no way of hooking up. I just hate not having that hooked up for safety reasons.

 

Tnfastbk

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It is a floor shift. I got the shift and kickdown linkage on today with a few minor mods. I just have to figure out what to do with the linkage that hooked up from the steering column to old fmx that kept you from putting the vehicle in gear without turning key on. I may just remove it if the C6 has no way of hooking up. I just hate not having that hooked up for safety reasons.
Thats what alot of folks do but just hang on to it for future use if you do remove it.

 

72HCODE

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just pull the cotter pin and take the linkage out from the steering column bottom, I had to do that :( then just hang onto the parts.

 

scvol

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Thanks for all the help fella's! Do ya'll think I am making a mistake by changing my fmx to c-6? I have a slightly modified cleveland that dynoed right at 350 hp.

 

72HCODE

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well other then the FMX being a bit heavier then the C6 and slightly harder to get rebuild parts for there is no difference, in that the gear ratios are the same.

the car might be 50 pounds lighter. they say the C6 is less efficient then the fmx. I've read guestimates that claim a 55-65% Drivetrain loss with a C6 and claim 45-55% loss with a FMX.

I know that the FMX can take a lot of power as well, not as much as a built up C6 but i've seen people with FMX transmissions holding 450+ HP no problem.

People tend to go with what is known, the c6 has proven itself and has a larger aftermarket following in support.

the FMX you can rebuild it but that is about it. there is no shift kits or upgrades for it.

i'm on the fence, at some point i'm going to have to ditch my C-6 for either another C-6 or a FMX

If i go back to a FMX i have everything i need. As for the C-6 i'm still missing some of the correct parts for the shifter lockout, also if i went back to a FMX i would have to change out my driveshaft.

so i don't know, its really up to you, if you car is running and everything works, i would just leave it be, why have the headache the trans won't blow up with 350hp, if your taking it to the drag track or road course once a week its another story.

 

scvol

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Yeah, that was my thought to. I needed the fmx rebuilt, but nobody wants to touch it around here and like you said there is no upgrades for it. The fmx is original so I will definatly hang onto it and just have the driveshaft lengthened another 4" if I go back with it.

 
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