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Well guys transmission is all done and installed on the truck. I used the stock Dodge clutch master cylinder bought one new. I also installed a new GM NV4500 slave cylinder and bought a braided clutch line 4ft long and used a Russel AN3 adapter on the the slave the clutch is the HD 12”LuK clutch for the install and it’s really stiff to depress only goes half way down to floor but does disengage the clutch. I definitely could use some tips and advice. I figured I’d have to mess with it I did get all the air bled out.
 

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Full travel is only 1/2 way down? Thinking that the Dodge clutch master cylinder is bigger in internal diameter than stock clutch master cylinder used with the GM slave cylinder. Look up the internal diameter of both master cylinders.

Sorry about the duplicate posts...
 

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Do you have the same amount of leverage on the master? On my '68 I am using the master/slave combo for the transmission but i have more pedal pressure that i should and it engages/disengages with only ~1/3 of the pedals travel,I have decided it is due to the relationship or the pedals pivot the master cylinder rods location and the length of the pedal. I plan to eventually go with a smaller Dia. master as my left knee is a bit FUBAR...I can operate it now well enough but as time goes on I'm in doubt...
 
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Definitely need a smaller bore master cylinder.
For those with external cylinders and air onboard something like the works well. Only requires around 10-15 PSI.
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Discussion Starter #5
The master is 1 1/8” bore and I think the Chevy nv4500 slave is either 3/4” or 7/8” had trouble trying to find the information 😂
 

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1 1/8 is brake master cylinder territory.
For leverage /advantage the master needs to be a smaller bore than the slave.
Cheers Steve
 

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Ya I’m not sure if making the pedal linger would help or not I knew I’d be taking a gamble on this setup in hopes to shave off on build time. The booster is a cool idea but would be an expensive route I bet. I may have to buy another master cylinder if I can’t make this work I have a bad right knee but as hard as that pedal is I’d have a bad left knee to match after a month 🤣
 

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Discussion Starter #8
Ya I figured it was because of the mismatch I’m not sure what’s gonna be the best route to go as far as what’s gonna be easiest to fab in there and make work with the slave.
 

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The boosted clutch slave is one option, Nissan and Toyota use a boosted master. I
could not fit one around the brake master on the F350 as the Aussie brake master has a stand off piece moving the master away from the firewall..
You really need to find out the slave bore then find a master that has a smaller bore.
Pic is an 85 Toyota Landcruiser setup. Do not know what is going on with the multiple pics being inserted
Cheers Steve
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The master is 1 1/8” bore and I think the Chevy nv4500 slave is either 3/4” or 7/8” had trouble trying to find the information 😂
Use the Doreman site it should be listed there it was for the different Ford master's
 

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The Dodge W300 master has a bore of 28.58mm or 1-1/8" where a Chevy or Dodge NV4500 is around 18mm or 11/16". That means the master cylinder rod travels about half as far and the pedal will be stiffer which is what you found. I believe the slaves on these were all around 19mm or 3/4". Not sure why the older Dodge had a much large master bore.
 
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