410/411 disc brake mod

[Paul G.]

Wow, what a read! There is a lot of information there Beelsebub, and many others contributed good info too. Worth a bump if nothing else :)

 

I have a '66 Datsun 411 wagon with aging drum brakes. This setup looks like quite an upgrade while I am mostly just looking to upgrade as needed to have parts available. I didn't give mine extra go so I don't really need extra stop. I've have some ideas about alternate parts to use but it may be more appropriate in its own thread. I would like to keep the stock 13 inch wheels.

[mklotz70]

It would keep it much more concise to keep the info in this thread....so share away :)

[Paul G.]

Shoot, just clicked the wrong button and lost my typing

 

The 411 brakes seem to be a pain to get parts for at every turn. I would like some upgrades/changes to allow more available parts to be used. Since front drums are getting rare I'm guessing some type of disc front, drum rear, conversion to "normal." I figure it would be best to start at the beginning...

 

Master Cylinder:

The Wilwood "High Volume Master Cylinder" is available in 3/4, 7/8, and 1 inch bores (p/n 260-6764 in 3/4 inch size.) The price is right at $62.10 list. The 2-1/4 inch attach pattern matches the 411. A new pushrod would have to be made and the correct bore chosen based on the rest of the brake system. Yes, it is still a single brake system but at least the reservoir is decent size and rebuild kits are available.

 

Rear Brakes:

I'm at a bit of a loss here but rear wheel cylinders in 3/4 inch bore seem more available. Just how close to converting the back brakes to 510 can I get? Even though this is my first area of concern it is the end I know the least about. I need a new left rear adjuster as mine is super stuck (in part because previous owners butchered the 1/4 inch square drive.) My right rear wheel cylinder is slightly leaking. I should repack the rear bearings while I'm in there.

 

Front brakes:

I started by looking for rotors that would fit the hub. I found a couple of possibilities. The 1980 Datsun 510 has a 225mm OD solid rotor with a 73mm hub bore that matches the 2-7/8 inch 411 hub. It would need to be redrilled for the 4.5 inch wheel bolt pattern and I don't know if it could be installed over the hub (it was originally designed to be installed on the inside of a hub and has a 4 bolt 95mm hole pattern.) Another option I found is the 1980 Fiesta rotor. The OD is 220.3mm. It comes drilled for the the 4.5 inch bolt pattern and is designed to be installed over the wheel studs. The hub bore is a bit small at 71.9mm but either the 411 hub could be turned, or the rotor could be bored, to fit.

 

I had a couple of idea for calipers. If the Fiesta rotor is used the caliper may work too. Wilwood makes some relatively inexpensive calipers like the Dynapro 2 piston caliper. New and complete these list for $116.80. Using a compact caliper should make it easier to stay away from everything else up there. Anyway, it appears that the front of the 411 is about the worst for parts availability. It actually looks easier to get the parts by going back to the 410 hydraulic dimensions all the way around (and all those vintage parts would be expensive!)

 

I've been looking over at datsunparts.com for stock brake parts because that is about the only source I've found. Has someone set up an interchange guide to help determine what parts actually fit these old 411's? I have a '66 WPL411. I'm just looking to get a working system made up of available parts.

[mklotz70]

Interesting info. You've got quite the challenge on your hands trying to get them to fit behind the 13" rims.

 

Something I learned years ago from someone on one of the yahoo forums.....if you're going to modify parts...it would be best to mod the "hard part". Meaning that instead of modifying the rotor to fit the hub, mod the hub to fit the rotor. That way, when it comes time to replace the rotor, you can do so without any more custom machining. Obviously, that is dictated by how close the diameters are and if you can take enough off the hub to fit(safely) :)

 

Do the SSS discs fit behind 13" rims?

[mklotz70]

Just a few more pics. I've actually been a bit active with the 411 stuff...selling the last kit and getting ready to turn some hubs for a previous buyer. Anyway...one of the questions asked was if there was an option that would fit behind stock 13" rim. Basically, the SSS setup is about the only way you're going to do it. Here's a some pics of turning the center out of a used rotor....practicing for a new one :) This buyer likes the idea of not having to send me his hubs...I can turn the rotors out and ship them with the kit. I also will be turning a set of hubs because that guy wants to be able to swap out rotors down the road without having to have them machined. Pros and cons each way, so it's up to the owner.

 

 

 

 

 

 

The pics in the rims are the G20 parts inside a 13x5.5" aluminum rim. It's kinda close...not sure the tape on weights would clear, but it clears the rim just fine.

 

 

 

 

 

 

 

 

The problem with fitting the stock 411 rim is the vent holes...more specifically, the way they are stamped. You can see the difference between the 510 rim and the 411 rim. The 411 rim is stamped into the area that the caliper wants. The G20 setup for the 411 will fit behind the stock 510 rim just fine. Does anyone know if the stock 411 caps will fit the 510 rim?

 

 

 

 

This isn't the g20 setup, but it's the 411 rim...you can see how the way the vent hole is stamped to encroach upon the caliper space.

 

[mklotz70]

In pursuit of an option for the stock 13's....I spent a bit over $80 on s/y calipers and new rotors to do some testing. These are 9 1/8" rotors/calipers off a Geo Metro(I've got the year, just don't have it handy). I can open up the center of the rotor just like the g20 rotor and it will slip right over the hub. I don't know if there's space for a bracket, but I didn't get that far. Basically, even with the small rotor, the caliper still hit the vent on the stock rim. Tons of clearance on the other rims, but no go on the one that counts. So....there's no point in pursuing that option any further. Reason: If the tiny rotors won't fit, you wouldn't gain anything by going any smaller...better to go with a SSS setup. If you have to change rims, even to use the Geo setup, you might as well go with the bigger/better G20 setup that fits the other rims anyway. From my side, I can't see anyone buying the Geo setup.....so I guess that $80 is going to end up on a shelf somewhere....maybe I can use it to mock up something else sometime. In case you're wondering...I bought two calipers since I wanted a matched set and if it worked, I'd need left and right. I could take them back to the yard and trade them for something else...I probably should...just didn't have the time. Same with the rotors....but after I got the one pretty dirty....anyway....the reality is, they're a pretty sweet little setup...I kinda wanted to keep them as an option for something else. ??? who knows :) You can see just how closely the Geo caliper and the Pulsar caliper match up! The difference is in the bracket that holds the pad. The Pulsar bracket will not fit over a vented rotor.

 

 

 

The top hub is the 1200...just as a comparison...about the same size as the 510. I was checking the Geo stuff against the 1200 to see if there was a cool vented option for it...nope...for the same reasons I wouldn't pursue it for the 411.

 

 

 

 

 

The slotted rotor is from the 1200 disc upgrade I did with Morrisun....again...since it doesn't fit behind the stock 13...it's not as good a choice as going with the g20 stuff for the 410/411.

[bananahamuck]

bump............................. to keep this where i can find it easier

[AZhitman]

 

Do the SSS discs fit behind 13" rims?

 

WRL411's (411 SSS) had 13" wheels from the factory. Mine wears 14's now, but the OEM 13's (that fit the OEM discs) are tucked away in storage.

[jeremiahnz]

Hi Guys,

 

Been watching this thread for a while.

 

Firstly, thanks for the awesome work, it is great that you have gone to so much effort on this. Anyway I thought I would try to offer some input (which may not be useful)

 

A couple of things I have been thinking about:

 

1) I am quite keen on not having to turn down the hubs to keep my 410 restorability as high as possible, but also don't want to have to bore out rotors each time they get replaced. I believe that the rotors therefore need to be 73mm bore

2) The welded ears on the brackets may cause cert issues - I understand in NZ that typically certifiers like to see either dowels or bolts through anything like this (based on discussions with a guy who works closely with a certifier on a regular basis)

3) If the rotor height was not as great, potentially the ears on the brackets would not be needed as the rotor would effectively sit further forward, therefore the caliper wouldn't need to be set back, and the custom bearing spacer may not be required. Given that the thickness of the bracket by which the caliper is recessed is 3/8 and the bearing spacer increases front spacing of the rotor by 1/8, a total of 1/2inch or 13mm would be the minimum height reduction of the rotor. Anything greater then that in reduction would mean forward spacing of the caliper.

 

I am not sure if the above is all correct, but thought I'd through it out there. I have also put together the attached table of rotors comparing some G20/P10 Primera rotors to some Vannette C20 rotors, that may do the job.

 

Let me know what is off the mark here and I will go look for alternatives.

[mklotz70]

Great info. I'm sure the 410/411 guys welcome any and all advancements and work on these models. I'm pretty much done with them.....not enough interest for me to make another batch.

 

I understand all you're concerns....luckily, here in the US, we don't have to worry about some of them. You're right about the rotor moving out.....keep in mind that as it pushes the caliper out, wheel clearance becomes more of an issue.

 

With the vented rotor.....it's going to be quite some time before it's worn out. Another option would be to find a Wilwood style setup....separate tophat and rotor. You could modify the top hat once, then just replace the rotor when needed. That would probably be the best choice. By moving the rotor/caliper further out, I don't think you'll need the longer spacer on the spindle. That was done purely to get clearance at the tierod nut.

 

Please feel free to carry on your work on this thread....it will help the poor search engine find the info later :)

[jeremiahnz]

Thanks for your reply. Based on what you have said it sounds like it is worth looking into. I presume higher positive offset mags could always help with any caliper clearance issues?

 

In your opinion do you think I would be best to start with the 245mm Dia, 35.5mm deep, 10mm thick rotor, or the 232mm dia, 22mm deep, 18mm thick rotor?

 

Again, thanks for all your work on this. It is really the only decent resource I could find anywhere on brake upgrades for these cars.

[mklotz70]

You're more than welcome. I didn't really do it for the cars....I did it for the challenge of it. I enjoy the design phase.

 

Without being able to see or check out the two rotor options, I'd probably opt for the second one. The smaller diameter will help with wheel clearance, but more importantly, the 18mm thickness would be a vented rotor. The 10mm has to be a solid rotor. Plus....the 22mm deep is a shorter top hat, pulling the rotor/caliper away from the spindle more, which is what your original post was about. :)

 

I chat with Doug, the owner of the 410 wgn I did the upgrade on.....he absolutely loves the brakes!! In fact, they drive the wgn all the time now. They were the only club members to actually show up with a datsun at the Christmas party! LOL

 

For wheel clearance, wilwood makes rotors that might have more clearance on the front side. I shy away from wilwood stuff just because of the price. I'm usually trying to create an option that can be repeated by others with minimal money. It would be a lot easier to make brake kits for these rigs if I thought people would spend $1500 on them. :)

 

Please take pics and post them here. Someone else may see something that neither of us are. :)

[jeremiahnz]

Just checked the rotors at the shop, and the above measurements from the catalogue are incorrect.

 

The Vanette rotor PCD is not 114.3, it is 95 so that won't work.

 

I have spent a few hours cross referencing information to try and find a rotor that will work of the shelf but so far no luck.

[mklotz70]

try googling brembo's catalog.....I think they had a good reference.....okay...just googled it...there's a "dimensions" tab to search by....great stuff. :)

 

http://bremboaftermarket.com/En/Car_Disc_Catalogue/Catalogue_Search.aspx?SearchMode=Size

[jeremiahnz]

Hey Mike,

 

Just a quick question, was there a reason you didn't look at mounting the calipers around the front of the rotor?

 

A couple of options I have found

1) Evo 1-3 Rotors and 2 pot calipers - they are a 276mm rotor with a 45mm height.

2) 200sx s13 Turbo rotors - these are a 280mm rotor and 49.2mm height.

 

Both are 4x114.3 but require the centre hole to be turned out

 

There are some advantages and disadvantages to both. If there isn't any reason not to mount the caliper at the front of the rotor, the taller rotor would probably be a better option as otherwise you may need to run higher positive wheels.

[mklotz70]

Actually, the first 5 or 6 pages of this thread was a version for the front....which didn't even come close to fitting because of the A arms. Check post #109 in this thread for a pic of the arms.

 

Keep in mind that the taller rotor also moves the caliper bracket closer to the A arms and spindle. You have to keep enough space between the back of the rotor and the front of the spindle so you have room for a bracket. I like making them out of 3/8"....you could go thinner...your life, your call :)

[mklotz70]

Just checking interest....

 

I may be making a 411 kit....I'd just as soon make two than one. If anyone is still following this thread and is serious about getting a kit....pm me. I'll still probably to two kits, but I'll just put the extra up on ebay when it's ready.

[erichwaslike]

possibly

[mklotz70]

Cool......but I see you have a SSS...which already has discs.....you'd need to find some drum hubs since this kit does not work with the disc hubs. The spindles are about the same, just the hubs are different. I think the mounting holes in the spindle are different...pass through instead of threaded??? Might require different hardware which you'd have to come up with. I only do the kit for the drum cars.

[ppeters914]

Cool......but I see you have a SSS...which already has discs.....you'd need to find some drum hubs since this kit does not work with the disc hubs. The spindles are about the same, just the hubs are different. I think the mounting holes in the spindle are different...pass through instead of threaded??? Might require different hardware which you'd have to come up with. I only do the kit for the drum cars.

You've handled/measured both drum and disc spindles, but, FWIW, there were different part numbers.

 

ALL: 40014-10650: ASS'Y-SPINDLE, knuckle with nut (R.H.)

ALL: 40015-10650: ASS'Y-SPINDLE, knuckle with nut (L.H.)

1.6L: 40014-16555: ASS'Y-SPINDLE, knuckle with nut

 

Pete

[mklotz70]

even a small difference like the left or right hand threaded spindle nut would get a different part number. Threaded holes or pass through holes would have different part numbers too. That's cool you got the factory numbers :)

[gcmustang]

Mike if you ever need to I have the part number books for 410/411 also

[mklotz70]

Thanks Greg!! ....although I that probably won't happen until I actually own a 411......and you know how I feel about them :) Have you posted pics of your wgn yet?

[mklotz70]

The two kits that I have in the works are already spoken for, but if anyone else wants a set....please speak up before I lathe the spacers. It will take an extra week or two to get the brackets cut, but I'd much prefer to do all the lathe work at one time! :)

[fivehunsky]

The two kits that I have in the works are already spoken for, but if anyone else wants a set....please speak up before I lathe the spacers. It will take an extra week or two to get the brackets cut, but I'd much prefer to do all the lathe work at one time! :)

 

I just saw this and I am interested in any possibility of upgrading my 411 to front disks.. What do I need and how much will it cost me :)