I would love to see some pictures. I was thinking that I’m going to have to notch the frame and am already planning that. I’m not going to redo the axel because it’s straight and it was a bitch to get it that way.
Matthew
RX-7 GSL-SE axle brake caliper orientation
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Mattk
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D P
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Re: RX-7 GSL-SE axle brake caliper orientation
So, to revive a year+ old thread, I started into my new rear-end this winter and thought that I would give my 2 cents worth to anyone who is considering this upgrade. There is lots of good info on this site, but there are still some details missing or deleted over the years. Who knows if I got them right, but here's my take on it. If this can help you, great, if not, no loss to you. (I'm not normally one to write on the internet in more than one sentence)
First off, any information listed is for reference only, and should not be assumed as accurate or correct. Please make your own measurements and judgments. Consult an expert if you are unsure; I am not one.
The stock Datsun rear-end is ~48.5" wide from the outside of each drum. I have a set of 14x7 +10 Panasports that I want to fit with lets say, wider than average tires on them. Based on test fits and a bunch of squinting, I figured if I made the new rear-end 3/4" narrower per side than the stock axle, with longer wheel studs, I could always space them back out, but it's harder to go the other way. So I settled on making it 47" wide.
The RX7 rear-end (1984 GSL-SE vented rotor version) measured up at 58.5" wide. Which means, lucky me, I get to end up with 11.5" of scrap steel.
It took me some time to track one of these rear-ends down, and the one I ended up with was a little worse for wear cosmetically, but was in good shape where it matters. I stripped it down and removed every bracket and widget on it with exception of the breather. I left the one mounting point on the middle-rear that you may see in the photos as I thought I may use it, but no, don't bother, cut 'er off too. Earlier on, I didn't take as may photos, so the timeline jumps around a bit, but here is what I started with, and then once stripped down (RX7 on top of the stock one).
The calipers turned out to be in good shape once they were scrubbed up. They were rebuilt and powder coated with Hawk pads installed. Same with the backing plates & brackets.
Narrowing the tube is fairly easy once you know how much you want to cut out. Grind the welds off the outer flanges, knock 'em off, mark the same distance from the end of the tube, cut, grind and hammer the flanges back on. Here you can see the welds missing, the tube already cut and smoothed out, and the flange hammered back on for mock up.
So far, this is all quite ordinary, however, you may notice that my brake caliper orientation is not as "ordinary".
Cue taking an operational car and making it not so functional, but hey, it's winter.
The spring perches sit 35" apart centre to centre.
The "up tilt" of the pinion angle is 5 degrees. You need to measure this for yourself to ensure it's right.
Once you're confident on the stock bracket locations, get out the grinder and do your worst. You'll need most of the brackets, and you've come this far, so take 'em all.
You'll have this pile left over when you're done.
Next, we do the centre section. What I can say is that I did a bunch of research on this before I tore into it and low and behold, some information I got off the internet was wrong (gasp). Refer to the FSM and don't trust all the self-described "experts" on the RX7 forums. However, once I opened it up it was pretty obvious that the RX7-keyboard-warrior was lost in left field.
I debated going torsion Miata, but my wallet won on this account. I'm not racing, and I've put 800kms on the car so far, so I don't think I'll wear the RX7 LSD out. I don't know the mileage of the car it came out of, but for how crusty it was on the outside, it was wonderful on the inside. I will vouch for the people that say these things last. Like lots of other accounts, my LSD shims measured like new.
The factory break-away torque is supposed to be around 35ftlbs, and when I checked mine, I was at 33. Not bad for being 35 years old.
First off, any information listed is for reference only, and should not be assumed as accurate or correct. Please make your own measurements and judgments. Consult an expert if you are unsure; I am not one.
The stock Datsun rear-end is ~48.5" wide from the outside of each drum. I have a set of 14x7 +10 Panasports that I want to fit with lets say, wider than average tires on them. Based on test fits and a bunch of squinting, I figured if I made the new rear-end 3/4" narrower per side than the stock axle, with longer wheel studs, I could always space them back out, but it's harder to go the other way. So I settled on making it 47" wide.
The RX7 rear-end (1984 GSL-SE vented rotor version) measured up at 58.5" wide. Which means, lucky me, I get to end up with 11.5" of scrap steel.
It took me some time to track one of these rear-ends down, and the one I ended up with was a little worse for wear cosmetically, but was in good shape where it matters. I stripped it down and removed every bracket and widget on it with exception of the breather. I left the one mounting point on the middle-rear that you may see in the photos as I thought I may use it, but no, don't bother, cut 'er off too. Earlier on, I didn't take as may photos, so the timeline jumps around a bit, but here is what I started with, and then once stripped down (RX7 on top of the stock one).
The calipers turned out to be in good shape once they were scrubbed up. They were rebuilt and powder coated with Hawk pads installed. Same with the backing plates & brackets.
Narrowing the tube is fairly easy once you know how much you want to cut out. Grind the welds off the outer flanges, knock 'em off, mark the same distance from the end of the tube, cut, grind and hammer the flanges back on. Here you can see the welds missing, the tube already cut and smoothed out, and the flange hammered back on for mock up.
So far, this is all quite ordinary, however, you may notice that my brake caliper orientation is not as "ordinary".
Cue taking an operational car and making it not so functional, but hey, it's winter.
The spring perches sit 35" apart centre to centre.
The "up tilt" of the pinion angle is 5 degrees. You need to measure this for yourself to ensure it's right.
Once you're confident on the stock bracket locations, get out the grinder and do your worst. You'll need most of the brackets, and you've come this far, so take 'em all.
You'll have this pile left over when you're done.
Next, we do the centre section. What I can say is that I did a bunch of research on this before I tore into it and low and behold, some information I got off the internet was wrong (gasp). Refer to the FSM and don't trust all the self-described "experts" on the RX7 forums. However, once I opened it up it was pretty obvious that the RX7-keyboard-warrior was lost in left field.
I debated going torsion Miata, but my wallet won on this account. I'm not racing, and I've put 800kms on the car so far, so I don't think I'll wear the RX7 LSD out. I don't know the mileage of the car it came out of, but for how crusty it was on the outside, it was wonderful on the inside. I will vouch for the people that say these things last. Like lots of other accounts, my LSD shims measured like new.
The factory break-away torque is supposed to be around 35ftlbs, and when I checked mine, I was at 33. Not bad for being 35 years old.
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D P
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Re: RX-7 GSL-SE axle brake caliper orientation
33ft/lbs of breakaway torque is not enough. The LSD works with a stack of clutches (friction discs and plates) within a housing, compressed together. The clamping force that the housing / springs provide sets this torque. So, more clamping = larger smiles. There are several ways to go about increasing this.
#1 - The most "proper" (read: expensive) way: Mazda sells 0.1mm (4 thou) oversized friction discs that you can replace your existing discs with to make the whole clutch pack wider relative to the housing, thereby increasing the pressure on the pack. This is super. Except my discs were near perfect, you'd need to buy multiple discs, and they're expensive. So this is a non-starter for me.
#2 - The forum recommendation: Some people recommend milling down the inner face of the housing, in essence making the inside dimension of the housing smaller achieving the same results as above. I'm not a fan. It's hard to do this in your garage, which means you're paying a machine shop, and if you haven't noticed a theme yet, that sounds expensive. Also, how much do you cut off? Get out the dart board; but don't take too much off of your unobtainium LSD. Also, if that didn't sound positive enough, since you're shrinking the size of the housing, that means the distance between the two carrier bearings has changed, and now you're into setting gear lash. While I like a challenge, as they say, "Ain't nobody got time for that". This whole idea seems fraught with headaches.
#3 - The best (read: cheapest) way: Shim stock and a pair of scissors. To help state the obvious, the clutches work by having one plate stationary relative to the housing (the friction plates) and ones that are stationary relative to the axle (the friction discs). How the pack is assembled, it goes housing, to the spring, which then presses on the first item which is a friction plate. Since the housing, spring & plate are all stationary to one another, adding in some material here is muy bueno. Since shim stock is cheap, it's easy to play around with various amounts. I got a roll of 5 thou sheet, as it's easy to cut with scissors. Make several shims by tracing your disc ID and OD, and you're in business. I settled on two spacers, one on each side of the pack, for a, you guessed it, 10 thou increase in "size". This increased the breakaway torque to 110ft/lbs and cost me $10. Winning.
The red arrow shows you where the shim goes on the one side, rinse & repeat for the other side. I didn't take any photos while I had it apart (and don't mind the clutter).
#1 - The most "proper" (read: expensive) way: Mazda sells 0.1mm (4 thou) oversized friction discs that you can replace your existing discs with to make the whole clutch pack wider relative to the housing, thereby increasing the pressure on the pack. This is super. Except my discs were near perfect, you'd need to buy multiple discs, and they're expensive. So this is a non-starter for me.
#2 - The forum recommendation: Some people recommend milling down the inner face of the housing, in essence making the inside dimension of the housing smaller achieving the same results as above. I'm not a fan. It's hard to do this in your garage, which means you're paying a machine shop, and if you haven't noticed a theme yet, that sounds expensive. Also, how much do you cut off? Get out the dart board; but don't take too much off of your unobtainium LSD. Also, if that didn't sound positive enough, since you're shrinking the size of the housing, that means the distance between the two carrier bearings has changed, and now you're into setting gear lash. While I like a challenge, as they say, "Ain't nobody got time for that". This whole idea seems fraught with headaches.
#3 - The best (read: cheapest) way: Shim stock and a pair of scissors. To help state the obvious, the clutches work by having one plate stationary relative to the housing (the friction plates) and ones that are stationary relative to the axle (the friction discs). How the pack is assembled, it goes housing, to the spring, which then presses on the first item which is a friction plate. Since the housing, spring & plate are all stationary to one another, adding in some material here is muy bueno. Since shim stock is cheap, it's easy to play around with various amounts. I got a roll of 5 thou sheet, as it's easy to cut with scissors. Make several shims by tracing your disc ID and OD, and you're in business. I settled on two spacers, one on each side of the pack, for a, you guessed it, 10 thou increase in "size". This increased the breakaway torque to 110ft/lbs and cost me $10. Winning.
The red arrow shows you where the shim goes on the one side, rinse & repeat for the other side. I didn't take any photos while I had it apart (and don't mind the clutter).
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D P
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Re: RX-7 GSL-SE axle brake caliper orientation
One point of note for option #3 above. I have not seen any internet chatter about doing it this way. Perhaps someone out there has done this in the past, but I couldn't find anything, which I find a tad odd.
So, perhaps I've overlooked something and this will not work (I'm not at the test-drive phase yet). However, the best I can squint while thinking about it, I believe it should work. But if it doesn't, keep your I-told-you-so's until I discover it the hard way.
So, perhaps I've overlooked something and this will not work (I'm not at the test-drive phase yet). However, the best I can squint while thinking about it, I believe it should work. But if it doesn't, keep your I-told-you-so's until I discover it the hard way.
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spyder
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Re: RX-7 GSL-SE axle brake caliper orientation
I go a different way. I have no breakaway friction and no wave plates. the diff feels like it is open without any torque on the input shaft. This allows me to coast through corners and not wear the clutches. Apply power and it locks up and gives two nice black streaks! When I had a tight diff the rear felt like it wanted to scoot around with anything except lite throttle.
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D P
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Re: RX-7 GSL-SE axle brake caliper orientation
Now that my housing shrunk, my axles are too long. I had Dutchman cut the equal amount off of the axles and re-spline them. Excellent quality, good to deal with, quick, and cost effective; I recommend them. $90 to do the set plus freight there & back.
I went with longer wheel studs, Moser # 8255. They are 1" longer than the stock RX7 ones, but the knurl is a tad larger, so hog the holes out very slightly prior to install (1/2" bit).
Now we're back to how this whole thread started. Where to put the calipers. From what Alvin shared earlier and other photos I've seen, the common way to do this is to put them in the 10 o'clock position (looking at the right-hand side wheel from the outside) and utilize the Datsun linkage to actuate the ebrake. See photo below which was shared earlier. To make the solid bar linkage work, one would have to cut the arm off of the shaft that actuates the ebrake, turn it 90 degrees and glue (weld) it back in place. Then, reinstall the Datsun bits, cut the rods to fit, and you're off to the races. This is fairly easy and near free; one may assume that this would be my preferred, cost-effective route. Nope.
Here's my rational:
#1 You are pretty much stuck with the calipers in the orientation shown.
#2 The Datsun linkage is designed for drum wheel cylinders which do not move in relation to the axle, so when the linkage pulls on them, the force of that pulling is exerted onto the backing plate they're affixed to (an obviously the shoes as well). With a floating caliper if you were to tug on the arm as shown, it would pull the calipers inwards. The force will also cause the arm to torque and apply pressure through the caliper as designed as well, so it will work. But, as the pads wear, the caliper shifts, and while driving, the linkage may inhibit some of the free-ness of the caliper to float as designed. The Mazda factory setup uses cables which pull through a bracket attached to the caliper, allowing the ebrake to work without affecting it's ability to float.
So, here's where I start contradicting myself. Yes, I won't put may miles on the car and wearing the pads/rotors much. Yes, the normal route is cheaper & easier. Yes, the normal route (I assume) works. However, I guess I do have "time for this".
I'm going to use the same cable style system that came with the RX7 and make it work with the Datsun chassis linkage. This also allows me to orient the calipers in a 10 o'clock or 2 o'clock position. Trial runs having the wife bounce the car while I held the caliper in place seem to determine that the forward position (2 o'clock on the RH side) actually has more frame clearance than the other way; so this answers my own first question. Other nice piece is we get to keep un-adulterated calipers.
Unfortunately, the factory RX7 cables are too short (at least on one side). They are inexpensive to buy new, which upsets my cheap heart that I can't use them. Enter custom made cables. The cable end fitting that goes to the arm on the caliper that Mazda uses was apparently only made in one factory that was decimated by a natural disaster and never replicated since. No luck getting anyone to make a cable with a matching end...
Fortunately, it's just the equivalent of a 3/8" rod. Drill & tap a 3/8" piece of bar (or a bolt in my case), and cut to size to make yourself the T piece. It is easy to get a cable made with a 1/4-28 end on it, which your franken-bolt screws on to.
And here's how it looks installed at the caliper. Don't worry, I''ll cut the tail off...
You'll need to open up the hole on the factory mounting bracket somewhat, as the standard bulkhead fittings are 9/16", but a die grinder solves that quickly.
I went with longer wheel studs, Moser # 8255. They are 1" longer than the stock RX7 ones, but the knurl is a tad larger, so hog the holes out very slightly prior to install (1/2" bit).
Now we're back to how this whole thread started. Where to put the calipers. From what Alvin shared earlier and other photos I've seen, the common way to do this is to put them in the 10 o'clock position (looking at the right-hand side wheel from the outside) and utilize the Datsun linkage to actuate the ebrake. See photo below which was shared earlier. To make the solid bar linkage work, one would have to cut the arm off of the shaft that actuates the ebrake, turn it 90 degrees and glue (weld) it back in place. Then, reinstall the Datsun bits, cut the rods to fit, and you're off to the races. This is fairly easy and near free; one may assume that this would be my preferred, cost-effective route. Nope.
Here's my rational:
#1 You are pretty much stuck with the calipers in the orientation shown.
#2 The Datsun linkage is designed for drum wheel cylinders which do not move in relation to the axle, so when the linkage pulls on them, the force of that pulling is exerted onto the backing plate they're affixed to (an obviously the shoes as well). With a floating caliper if you were to tug on the arm as shown, it would pull the calipers inwards. The force will also cause the arm to torque and apply pressure through the caliper as designed as well, so it will work. But, as the pads wear, the caliper shifts, and while driving, the linkage may inhibit some of the free-ness of the caliper to float as designed. The Mazda factory setup uses cables which pull through a bracket attached to the caliper, allowing the ebrake to work without affecting it's ability to float.
So, here's where I start contradicting myself. Yes, I won't put may miles on the car and wearing the pads/rotors much. Yes, the normal route is cheaper & easier. Yes, the normal route (I assume) works. However, I guess I do have "time for this".
I'm going to use the same cable style system that came with the RX7 and make it work with the Datsun chassis linkage. This also allows me to orient the calipers in a 10 o'clock or 2 o'clock position. Trial runs having the wife bounce the car while I held the caliper in place seem to determine that the forward position (2 o'clock on the RH side) actually has more frame clearance than the other way; so this answers my own first question. Other nice piece is we get to keep un-adulterated calipers.
Unfortunately, the factory RX7 cables are too short (at least on one side). They are inexpensive to buy new, which upsets my cheap heart that I can't use them. Enter custom made cables. The cable end fitting that goes to the arm on the caliper that Mazda uses was apparently only made in one factory that was decimated by a natural disaster and never replicated since. No luck getting anyone to make a cable with a matching end...
Fortunately, it's just the equivalent of a 3/8" rod. Drill & tap a 3/8" piece of bar (or a bolt in my case), and cut to size to make yourself the T piece. It is easy to get a cable made with a 1/4-28 end on it, which your franken-bolt screws on to.
And here's how it looks installed at the caliper. Don't worry, I''ll cut the tail off...
You'll need to open up the hole on the factory mounting bracket somewhat, as the standard bulkhead fittings are 9/16", but a die grinder solves that quickly.
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D P
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Re: RX-7 GSL-SE axle brake caliper orientation
As a note, I am still using the right side caliper on the right side, however it is now upside down. The bleed screw is not in the ideal spot, which is a slight bummer, but of all the issues, popping the caliper off to bleed it properly does not seem insurmountable.
I purchased new U bolts from uboltsdirect.com and they fit perfectly. Their SKU is: R05 - (3/8" x 2 1/2" Inside Width) x Length: 5 7/8"
Getting the end caps glued back on straight is relatively important. I bought a sacrificial set of bearings (6207) and some TGP 1-3/8" shaft to hold things straight while they got tacked up.
The spring perches got tacked in the right spot and it's time for a trial fit. Now that it's in place, it's time to start sorting the other details. Brake plumbing, ebrake, drive shafts, etc.
Sleep well knowing that my family does not need to survive on my photography skills.
Next up: driveshaft.
The RX7 rear end is actually ~3/4" shorter from the centre of the axle to the input flange. Normally this is where you take your RX7 & Datsun driveshafts to a driveshaft shop and hand them cash to make you a new one. I'm clean out of cash since buying my fancy ebrake cables, so what to do?
Call your buddy with a 5-axis CNC machine and get him to make you a spacer/adapter thingie. Now your original drive shaft still works, making this even more bolt on friendly. I took a stab at creating the model for this, and after one small but important oversight, we were off to the races. Cost: a couple bottles of rum.
I purchased new U bolts from uboltsdirect.com and they fit perfectly. Their SKU is: R05 - (3/8" x 2 1/2" Inside Width) x Length: 5 7/8"
Getting the end caps glued back on straight is relatively important. I bought a sacrificial set of bearings (6207) and some TGP 1-3/8" shaft to hold things straight while they got tacked up.
The spring perches got tacked in the right spot and it's time for a trial fit. Now that it's in place, it's time to start sorting the other details. Brake plumbing, ebrake, drive shafts, etc.
Sleep well knowing that my family does not need to survive on my photography skills.
Next up: driveshaft.
The RX7 rear end is actually ~3/4" shorter from the centre of the axle to the input flange. Normally this is where you take your RX7 & Datsun driveshafts to a driveshaft shop and hand them cash to make you a new one. I'm clean out of cash since buying my fancy ebrake cables, so what to do?
Call your buddy with a 5-axis CNC machine and get him to make you a spacer/adapter thingie. Now your original drive shaft still works, making this even more bolt on friendly. I took a stab at creating the model for this, and after one small but important oversight, we were off to the races. Cost: a couple bottles of rum.
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Gregs672000
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Re: RX-7 GSL-SE axle brake caliper orientation
Really admire your work. I don't recall needing any changes to my 5 speed drive shaft or a spacer however. The hand brake has never worked well on my conversion no matter how much I've played with the linkage. Nice work!
Greg Burrows
'67 2000 #588
Tacoma, WA
'67 2000 #588
Tacoma, WA
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D P
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Re: RX-7 GSL-SE axle brake caliper orientation
Thanks Greg, appreciated. I'm running a CA18DET which I probably should have mentioned to start with, but the RX7 flange is still 3/4" further away compared to the Datsun. Minor issue with the length of the slip joint, the main issue is you can only get one bolt in on an angle 
So, onwards. The calipers are in place, wheel test fits can be accomplished, but next we need to attach the inboard ends of the ebrake cables. For that we're going to need a bracket.
This is way thicker steel then needed for this, but it's what I had laying around that worked. Some fusion welding with the tig. The thicker it is, the better my (perceived) skill. Even a blind pig...
It was a little too thick to bend in the vice without a torch, so I ground a groove out to allow bend, then added some glue to the inside. Not quite as pretty, but it'll hold.
Affix in a semi-scientific method and away you go. I jacked up the car by the rear end, so that the springs were compressed so that the rear end was at its normal position when the brake would be applied, and using the gold threaded rod you saw above as my sights, aimed it straight at the chassis ebrake linkage to keep things somewhat straight.
Glue as required.
I made a little balance bar with a piece of square tube cut in half length-ways and popped some holes in it.
Its hard to see in this picture, and the axle is at full droop so it looks funny, but here you can see the factory cable that leaves the chassis towards the rear end. I cut it to length and crimped a bullet end stop on it. It all seems to work. FYI, the travel that the RX7 cables had was 2". The travel from the chassis was also 2". Nice.
As for the cables, I sourced them from California Push Pull. They were one of the only online custom cable shops that returned my email. Their service was very good, even calling me to offer some advice to decrease my chances of failure. They whipped them up and shipped them for less than their estimated price and I got them in just a few days. Their online "book" is difficult to use in my opinion, but once you learn to think like they do, it makes sense.
My assembly part #s are/were:
RHS cable: TE523-001-060-19.5-060-TE523-001-29.75-3
LHS cable: TE523-001-060-37-060-TE523-001-47.25-3
California Push-Pull
So, onwards. The calipers are in place, wheel test fits can be accomplished, but next we need to attach the inboard ends of the ebrake cables. For that we're going to need a bracket.
This is way thicker steel then needed for this, but it's what I had laying around that worked. Some fusion welding with the tig. The thicker it is, the better my (perceived) skill. Even a blind pig...
It was a little too thick to bend in the vice without a torch, so I ground a groove out to allow bend, then added some glue to the inside. Not quite as pretty, but it'll hold.
Affix in a semi-scientific method and away you go. I jacked up the car by the rear end, so that the springs were compressed so that the rear end was at its normal position when the brake would be applied, and using the gold threaded rod you saw above as my sights, aimed it straight at the chassis ebrake linkage to keep things somewhat straight.
Glue as required.
I made a little balance bar with a piece of square tube cut in half length-ways and popped some holes in it.
Its hard to see in this picture, and the axle is at full droop so it looks funny, but here you can see the factory cable that leaves the chassis towards the rear end. I cut it to length and crimped a bullet end stop on it. It all seems to work. FYI, the travel that the RX7 cables had was 2". The travel from the chassis was also 2". Nice.
As for the cables, I sourced them from California Push Pull. They were one of the only online custom cable shops that returned my email. Their service was very good, even calling me to offer some advice to decrease my chances of failure. They whipped them up and shipped them for less than their estimated price and I got them in just a few days. Their online "book" is difficult to use in my opinion, but once you learn to think like they do, it makes sense.
My assembly part #s are/were:
RHS cable: TE523-001-060-19.5-060-TE523-001-29.75-3
LHS cable: TE523-001-060-37-060-TE523-001-47.25-3
California Push-Pull
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Last edited by D P on Sun Feb 16, 2020 10:48 pm, edited 1 time in total.
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D P
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Re: RX-7 GSL-SE axle brake caliper orientation
Once the axle tube was cut to my desired width and mocked up, I realized that the calipers will clear the frame rail under even compression, but when the axle articulates, they may hit the frame rail; not ideal. In hind sight, perhaps going to stock width (+3/4" per side) would ease or remove this potential, something for you to think about if you're still in the planning stage. But alas, the tube is cut and here we are. I decided that some bump stops would be better to hit than the calipers, so I made up a set and glued them to the top bracket that is held on by the u-bolts, so if it turns out to be a terrible idea, they are quickly removable. I also used stops with an integrated stud, and made my brackets with a captive nut, so if I need to adjust them up, it's as simple as threading them out, inserting a spacer, and reinstalling. If we need to go the other way, spin them out, trim off some poly and reinstall.
Bump stops are the same as what I'm using up front, which is one of the only consistent things on the whole car, so there's that...
Prothane 19-1317-BL Black Cone Type Bump Stop - eBay link
It turns out that their OD is the same as 1-1/4" black pipe that I had laying around from installing the bearings onto the RX7 axles, so that's nifty.
Adding on a tab for the brake tube, nuts for the brake tee and a few clamps.
And here she is ready to be installed.
Bump stops are the same as what I'm using up front, which is one of the only consistent things on the whole car, so there's that...
Prothane 19-1317-BL Black Cone Type Bump Stop - eBay link
It turns out that their OD is the same as 1-1/4" black pipe that I had laying around from installing the bearings onto the RX7 axles, so that's nifty.
Adding on a tab for the brake tube, nuts for the brake tee and a few clamps.
And here she is ready to be installed.
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GoldHawg
- Roadsteraholic
- Posts: 591
- Joined: Sun Jul 30, 2006 3:27 pm
- Location: Spring Valley, OH
Re: RX-7 GSL-SE axle brake caliper orientation
Thanks for documenting your progress; nice approach on the e-brake cable. FYI, another site I found exceptionally helpful on this to build one is here:
https://toyanvil.smugmug.com/Hobbies/19 ... xle-build/
https://toyanvil.smugmug.com/Hobbies/19 ... xle-build/