I've been off-and-on considering a disc brake conversion for a while now. I intend to keep the I-6, so I don't really need to upgrade to V8 spindles/steering. However, I already have an 8" diff installed, so it would be nice to have 5 lugs up front.
My questions pertain to the proportioning valve. I currently have a new single bowl / manual brake master cylinder installed (which I intend to keep). First question- do I need a proportioning valve (I assume yes, but the item description says "proportioning valve required for some applications")? Second question- does the proportioning valve go on the front or rear brake line? Finally, what all will I need to do for the installation of the valve?
Thanks as always!
__________________ '65 coupe, 200ci, T5spd, Silver Smoke Gray, Std Red Interior '03 convertible, V6, auto, Silver Metallic, Black Top '14 coupe (on order- ETA 05/30/13), Sterling Gray, 5.0, 6spd, Track Pack, Glass Roof, Brick Red interior
Given the conversion is "at the wheel," I'm not anticipating changing the master cylinder or the distribution lines.
So, the proportioning valve is used to keep the rear brakes from locking up (do discs require more pressure to activate)?
What is involved with installing the valve? I'm guessing I need to cut the rear brake line and somehow install threaded ends for the valve (does that require a flaring- or some other kind of- kit)?
__________________ '65 coupe, 200ci, T5spd, Silver Smoke Gray, Std Red Interior '03 convertible, V6, auto, Silver Metallic, Black Top '14 coupe (on order- ETA 05/30/13), Sterling Gray, 5.0, 6spd, Track Pack, Glass Roof, Brick Red interior
So, the proportioning valve is used to keep the rear brakes from locking up (do discs require more pressure to activate)? About double the pressure. Without the valve, the drums will lock before the discs would even get warm.
What is involved with installing the valve? I'm guessing I need to cut the rear brake line and somehow install threaded ends for the valve (does that require a flaring- or some other kind of- kit)? Not really. Disconnect the rear line from the divider block. Attach the line to the outlet on the valve. Use a short standard replacement line to connect the valve inlet to the divider block.
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Amateur restorer. (Well, once in a while I have been paid for it)
I understand the benefits of having the dual MC, but is it absolutely necessary? I mean, there is a single line running to the rear brakes- seems like the valve could just be installed in that line.
As far as Chockostang, I've heard nothing but good things- but I haven't seen an "at the wheel" conversion on either his or the discbrakeswap site- plus, once I do the write-up, the CJ route will end up costing about $600.
__________________ '65 coupe, 200ci, T5spd, Silver Smoke Gray, Std Red Interior '03 convertible, V6, auto, Silver Metallic, Black Top '14 coupe (on order- ETA 05/30/13), Sterling Gray, 5.0, 6spd, Track Pack, Glass Roof, Brick Red interior
+1 on the "1 word.. Chockostang.."
I talked to him the other day about doing the conversion on my 66 and he knows the ins and outs of any combination you want to do.
As a side note I tried to find a better price (even did it piece by piece) and he came in WAY under even with shipping included.
I guess I will call Chockostang and get his advice first.
Regarding the reimbursement for writing instructions, I've submitted four sets of instructions and been paid for all four, so it seems to be a pretty good program as far as I'm concerned!
__________________ '65 coupe, 200ci, T5spd, Silver Smoke Gray, Std Red Interior '03 convertible, V6, auto, Silver Metallic, Black Top '14 coupe (on order- ETA 05/30/13), Sterling Gray, 5.0, 6spd, Track Pack, Glass Roof, Brick Red interior
I understand the benefits of having the dual MC, but is it absolutely necessary? I mean, there is a single line running to the rear brakes- seems like the valve could just be installed in that line.
As far as Chockostang, I've heard nothing but good things- but I haven't seen an "at the wheel" conversion on either his or the discbrakeswap site- plus, once I do the write-up, the CJ route will end up costing about $600.
I consider the dual MC necessary. You could get by without it but there's a reason every car on the road since 1967 has one.
I'm not sure if I understand what you mean by "at the wheel" but the chockostang swap is all OE style parts which will replace what you have now without having to replace your spindles like most swaps out there. For the most part it's as simple as removing the 4 bolts to the drum brake assy and the hose, then start mounting the bracket, dust shield, rotor, caliper and connect the hose. Swap out the MC and install the proportioning valve inline with the rear brakes, bleed brakes and you're pretty much done. The only issue I've run into was rounding off some nuts trying to remove brake lines from the distribution block so I'm waiting on a brake line kit from Classic Tube so I can finish up. Keep in mind that you're working on a 47 year old car so if it's your only transportation make sure you have a backup plan in case you end up having to order something.
I consider the dual MC necessary. You could get by without it but there's a reason every car on the road since 1967 has one.
I completely understand the argument. Considering my single MC is brand new (along with the brake lines and rear drum cylinders)- and the fact that I've driven single MC Mustangs for years with no issues- I just do not consider it necessary.
I'm not sure if I understand what you mean by "at the wheel."
By "at the wheel," I mean pretty much exactly what you described- I want a kit that bolts on at the wheel using the same 6 cylinder spindles and steering linkage. Again, everything up front in my car is solid- so I just don't see the necessity to upgrade to V8 parts.
__________________ '65 coupe, 200ci, T5spd, Silver Smoke Gray, Std Red Interior '03 convertible, V6, auto, Silver Metallic, Black Top '14 coupe (on order- ETA 05/30/13), Sterling Gray, 5.0, 6spd, Track Pack, Glass Roof, Brick Red interior
The problem as I understand it is that a drum brake requires some residual pressure in the line to give you a solid feel at the pedal, hence the installation of a residual brake valve in the master for Drum brakes. Disk brakes need all pressure relieved.
Soo, when I put a Drum Drum dual master cylinder in, I had to go through the extra step of removing the brake line seat and removing the rubber residual valve and spring for my disc brake circuit.
Sooo, it is likely that your old drum-all-the-way-around death trap baby food jar system has a residual valve that could make your discs drag - not good. Grab a 70 Maverick disc/drum master for peanuts and be glad you have a backup system.
My 2001 VOlvo blew a front hose last week on a hill (No Chit!!) - mfg defect I was very glad that I had the rear brakes on a separate circuit with my son in the front seat besides me. It may be ok with you not to have a backup system but would your passengers make the same decision knowing there are 40+ yr old components in it?
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Proportioning Valve Question...
I was very glad that I had the rear brakes on a separate circuit with my son in the front seat besides me. It may be ok with you not to have a backup system but would your passengers make the same decision knowing there are 40+ yr old components in it?
