[DeTomaso] Working on dual MC conversion like Goran (Hemi Pantera) did, Anyone have ideas?

[richard boschert]

Ken,
I have the whole SAAC manual brake twin master cylinder conversion with the pedals.
If you want to go  without power assist you MUST change the pedal ratio!The power booster makes a huge difference in pedal effort required.I cannot emphasize how much effort it will take to stop the car without power assistance. 

I have the wilwood 6.25 to 1 pedals.I dont remember the piston sizes on my wilwood superlite calipers,but they were not that large.I originally had twin 7/8 bore masters,but i dropped down to 3/4 bore masters,due to the pedal effort.Pedal travel is minimal.Effort is still high but manageable.It is really too high for 99 percent of the people in a street car.
The online calculator i used took in all kinds of factors. Car weight as well as weight bias front to rear,center of gravity,rotor size ,caliper piston size,etc.For what its worth my car weighs 2700 lbs so it allowed a larger bore master as it assumes it will be easier to stop with less mass vs a stock panteras 3200 pounds.

It came up with the 7/8 bore masters under high effort,race car and 3/4 bore masters under moderate effort race/street.Im actually tempted to try 5/8 bore masters,as it is really a street car.

I don't think you could go a small enough bore size in the master cylinder with the stock pedal ratio.I do not know what the stock pantera ratio is but most cars have a power assisted ratio around 5 to 1.By the time you got the bore size down to a usable leg effort the pedal travel would be very far.Probably so far you could not lock up the brakes before the pedal hits the floor.They may not even make a brake master that small.
The unexpected HUGE  plus of going with the SAAC setup or making your own plate with better ratio pedals vs the stock mounting plate and pedals is a drop in pedal effort for the clutch,and more room for your feet!
Without a power booster in the way and wilwood pedals,the clutch master is now a normal straight pushrod versus the stock jackshaft offset master cylinder.I can also now wear normal shoes versus before i had to wear narrower driving shoes.The clutch is so much easier to use now and i had the effort reduction kit.To me this is as a big a selling point or more so than  the weight reduction which was my original reason for doing the conversion.
Hope this helps make your decision on what to do.
Richard


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   Ken,
   I have the whole SAAC manual brake twin master cylinder conversion with
   the pedals.
   If you want to go  without power assist you MUST change the pedal
   ratio!The power booster makes a huge difference in pedal effort
   required.I cannot emphasize how much effort it will take to stop the
   car without power assistance.
   I have the wilwood 6.25 to 1 pedals.I dont remember the piston sizes on
   my wilwood superlite calipers,but they were not that large.I originally
   had twin 7/8 bore masters,but i dropped down to 3/4 bore masters,due to
   the pedal effort.Pedal travel is minimal.Effort is still high but
   manageable.It is really too high for 99 percent of the people in a
   street car.
   The online calculator i used took in all kinds of factors. Car weight
   as well as weight bias front to rear,center of gravity,rotor size
   ,caliper piston size,etc.For what its worth my car weighs 2700 lbs so
   it allowed a larger bore master as it assumes it will be easier to stop
   with less mass vs a stock panteras 3200 pounds.
   It came up with the 7/8 bore masters under high effort,race car and 3/4
   bore masters under moderate effort race/street.Im actually tempted to
   try 5/8 bore masters,as it is really a street car.
   I don't think you could go a small enough bore size in the master
   cylinder with the stock pedal ratio.I do not know what the stock
   pantera ratio is but most cars have a power assisted ratio around 5 to
   1.By the time you got the bore size down to a usable leg effort the
   pedal travel would be very far.Probably so far you could not lock up
   the brakes before the pedal hits the floor.They may not even make a
   brake master that small.
   The unexpected HUGE  plus of going with the SAAC setup or making your
   own plate with better ratio pedals vs the stock mounting plate and
   pedals is a drop in pedal effort for the clutch,and more room for your
   feet!
   Without a power booster in the way and wilwood pedals,the clutch master
   is now a normal straight pushrod versus the stock jackshaft offset
   master cylinder.I can also now wear normal shoes versus before i had to
   wear narrower driving shoes.The clutch is so much easier to use now and
   i had the effort reduction kit.To me this is as a big a selling point
   or more so than  the weight reduction which was my original reason for
   doing the conversion.
   Hope this helps make your decision on what to do.
   Richard