Hi... new to forum. Single to Dual MC conversion question.

[bluefury361]

Funny how folks are so quick to "condemn" the single reservoir master cylinder. Last used as OEM in 66 ? Almost 55 years ago. An overwhelming percentage of brake failures were likely the result of rusty brake lines or lack of maintenance. Not checking the brake fluid level on a regular interval.
If your 55 or older car still has a single master cylinder, go look at the front end..... Any damage?
Although there may be an advantage to a dual system it's not as big a safety concern as some make it out to be.
Unless you have modified the engine for additional horse power, and will be driving aggressively, it might be wiser to spend the money elsewhere. JMHO

 

[ascari]

@bluefury361 - A 55 year old master cylinder is a 55 year old master cylinder, and if the fluid hasn't been changed in say half of those years I won't trust it. So it would have to go. A good quality dual MC will set me back 30 bucks. A good quality single "tea pot" MC as found on my -66 will set me back about twice that. So in fact I'm saving money going dual MC.

The brake lines are a different matter, if they don't look OK swap them out. Cost is the same for dual or single except for that extra two foot length from the MC and two fittings. To me it's a no brainer to go dual.

 

[bluefury361]

@bluefury361 - A 55 year old master cylinder is a 55 year old master cylinder, and if the fluid hasn't been changed in say half of those years I won't trust it. So it would have to go. A good quality dual MC will set me back 30 bucks. A good quality single "tea pot" MC as found on my -66 will set me back about twice that. So in fact I'm saving money going dual MC.

The brake lines are a different matter, if they don't look OK swap them out. Cost is the same for dual or single except for that extra two foot length from the MC and two fittings. To me it's a no brainer to go dual.

I understand the logic behind the swap. You missed my point. I would not use any 55 year old master cylinder. Just that the swap isn't all that necessary from a safety stand point.
Those purists out there might like to keep the OEM look. No reason not to.

 

[ascari]

OK I see what you're saying. Since I don't care that much about the original look it made sense for me to go dual using the -67 and upward unit. I am keeping the OEM MC in case I ever want to go back to bone stock. Or for my kids to haul to the dump when I'm dead, whichever comes first.

 

[Big_John]

I understand the logic behind the swap. You missed my point. I would not use any 55 year old master cylinder. Just that the swap isn't all that necessary from a safety stand point.
Those purists out there might like to keep the OEM look. No reason not to.

I agree with you with one caveat. The quality of replacement parts can be a little marginal these days. We've both had problems with new, offshore sourced, brake cylinders, so I think you'll agree that it can give you some pause for thought if old parts aren't able to be rebuilt or a previous owner has used off shore parts and the old stuff is gone.

Personally, I've done conversions to older cars, my '65 Barracuda being one. I also did a '62 D-100 because I drove it everyday and it didn't get pampered at all. I have had brake failures with a few cars over the years (high usage daily drivers with lots of winter miles), so I like having the dual master... Nothing like suddenly having a brake pedal drop to the floor... Once I didn't get a chance to pump the brakes and a Dodge Omni bounced pretty hard when I bumped it with the old NYB I had... LOL.

But, a limited use car with ALL components at 100% has a pretty low chance of failure, no doubt about that.

 

[bluefury361]

I agree with you with one caveat. The quality of replacement parts can be a little marginal these days. We've both had problems with new, offshore sourced, brake cylinders, so I think you'll agree that it can give you some pause for thought if old parts aren't able to be rebuilt or a previous owner has used off shore parts and the old stuff is gone.
.

I bought a full set of new wheel cylinders for the Polara, rears twice, and had issues with all, (Raybestes boxes but obvious lesser quality). I ended up using the seals and internal parts to rebuild the originals.
Good used cores are pretty available, if you don't have them, as are rebuild kits. A wire brush and a hone and your good to go with OEM parts. I haven't had any issues with remanufactured or new Master cylinders but the same applies to them.