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Looking great. Did you have any future plans for possible hydroboost braking? Those units take up far less firewall space than the vacuum booster. Your engine compartment is really looking good. Very neat and well organized.
 

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Discussion Starter #462
Looking great. Did you have any future plans for possible hydroboost braking? Those units take up far less firewall space than the vacuum booster. Your engine compartment is really looking good. Very neat and well organized.
Thanks! And yes, I would like to do that when I do the other brake upgrades.

I did get that brake proportioning valve installed, & also ditched some aluminum swivel-unions for steel versions. I personally much prefer all the brake fittings be steel or stainless. The tee-fitting off the valve is roughly the same height as the master's reservoir, but AN fittings are typically fairly easy to bleed at the connection, so there shouldn't be too much to worry about causing a "bubble trap". If I had a lathe I would've taken some extra time to make adapters to save the need for those swivel-couplers that add length to the assembly, even though they may be handy for installation/positioning:
 

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Discussion Starter #463
Finished the video on the ABS delete process for the Disco. After the fact I spotted a few places that could do with some spiral wrap protection, as well as a few more zipties. Also I had planned to build a little support bracket for the valve, but with these steel fittings I was impressed how rigid the whole assembly is! Oh & since I have a habit of spacing out on things when I get excited to drive a project again... I stuck a big piece of tape to the window saying "Bleed the Brakes!"

 

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Discussion Starter #465
Nice movie, wish I was such a fast worker.

Ed
Sometimes I think it might be kinda funny to sneak a stopwatch in the corner of all the shots just to show how long it really takes me, without the magic of editing... but at the same time I'm not sure I wanna know if (when) it takes me 17 hours to make a little bracket.

Now with all the ABS scraps out of the way I could move on to the work that needs doing to the pedalbox. I picked up another from a salvage yard, partly because it's less rusty than mine & also because I needed another brake pedal that'll become my clutch pedal. None of the US market Disco 2's had manual transmissions, but thankfully it's the same pedalbox design as the euro versions that did. If you look close you can see the brake pedal pivots on a shared shaft that stretches across to where the clutch pedal would be & another hole is there for the clutch interlock switch. So I'm mounting that second brake pedal right across from my original one & even using the same hardware. May have to bend the new pedal slightly for ergonomics, but for sure I'll need to poke a hole thru the pedalbox firewall plate for the Dodge master/slave kit & modify the pedal's pivot-pin to match.


While that was all out of the way I had to take care of a bad spot of rust right between 2 of the upper mounting bolts. At the same time I scrubbed down the remainder of the driver's side fenderwell for paint to match. It's the last area of the engine bay that needed a look over for corrosion & recoating to keep it that way:


So much better! I'll reseal the seams I cleaned out, but I prefer to give the paint plenty of cure time beforehand. While it sets up I can move on to modifying the pedal box for the clutch & throttle. And then I can decide on a new home for the steering reservoir so I can get that system reconnected again.
 

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Discussion Starter #466
Making progress on the list of things between me & a test drive. I'll have my clutch connections sorted & driveshafts back this week, then I'm on to reconnecting the steering & building a custom bellcrank throttle linkage. Should be behind the wheel here in a few weeks, even though I do have a habit get distracted easily by my other projects... some of the diversions are worth it, like getting my CRX rally car running again after nearly 5 years of collecting dust. Only 1 non running vehicle left in my "fleet" of garbage :D

I test fit the second brake pedal into the assembly using the same assortment of parts as the other pedal. It leaves the pedals a little too close for my liking, but at the same time it's left me with more room between it & the left side of the footwell than I was expecting for this idea:


I figured the easiest thing to do was to split the the pedal lever as low as I could, then weld the hub back in place flipped 180 degrees. I have no doubt that's how the clutch pedal on Disco's outside the US would look (it's a damn shame we didn't get the manual gearboxes OR the diesels here!). The welds need to be stout enough to take plenty of kicks without fail, so I gave it a healthy taper with the grinder & sunk as much heat in it as the 110V welder can manage, taking extra care to keep the 2 halves as square & straight as possible:


Here's the pedalbox back together, & man was modifying that spring not fun at all. Several bruised fingers, a bit of blood letting, & no shortage of aggressive words invested into bending the spring into a mirrored shape to contour to the new pedal. Not only does the cut & welded lever set the pedal spacing up nicely, but it also aligns the lever back under the sensor hole (the funny cross shaped holes just behind the orange clips). The brake already had the brake light switch there in the hole, so now I'll have the option of running a clutch interlock switch as well:


There we go! I like it when a harebrained idea comes together the way I'd hoped. The spacing is perfect, & plenty of clearance all around. Now I need to poke a hole in the plate for the master cylinder & modify it's pushrod to meet the new pedal:
 

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Yeah, normally the clutch pedal has a smaller pad than the brake but your solution looks great. One thing I was thinking, since you're working all that out, why not change to the hydroboost now? You could have that out of the way when the future brake system goes in.
 

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Discussion Starter #468
Yeah, normally the clutch pedal has a smaller pad than the brake but your solution looks great. One thing I was thinking, since you're working all that out, why not change to the hydroboost now? You could have that out of the way when the future brake system goes in.
Early on I had thought about changing the pedal itself... but there's just something funny about the new clutch pedal looking like a clone of the brake pedal. Well I'm kind of curious to compare the difference since I've never driven on hydroboost brakes. And honestly I can't see much else use for that vacuum pump afterwords, unless someone has another idea? Most likely going to look for some sort of replacement in the future (e.g. air compressor). And my brakes will definitely get more upgrades in various phases (more stainless hose, fixed calipers, big rotors, etc).
 

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Vacuum on hydroboost setups could be for things like heater/ac controls or cruise control. On most modern diesels they changed to an electric vacuum pump since there wasn't a need for the big mechanical one. I believe there are even vacuum lockers for differentials. Otherwise, it would have little to no use. An air compressor would be a possible, but there you'd need to figure out the ps setup. No adapter that I know of that fits the stock pump to one of those. There you'd use a different ps pump and remote reservoir. Those type pumps are usually higher pressure since they came on medium duty trucks but they can usually be adjusted to work with the hydroboost system. There were single and twin cylinder compressors and they were even on P pump engines. Here's a photo of a twin on a 4bt with the VE injection pump. Like I said, they came on P pumps too. One note, those puppies aren't light because they are cast iron, not aluminum. Would require a bit of research for your engine to get the correct mount and braces to support that pump.
 

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Discussion Starter #470
Vacuum on hydroboost setups could be for things like heater/ac controls or cruise control. On most modern diesels they changed to an electric vacuum pump since there wasn't a need for the big mechanical one. I believe there are even vacuum lockers for differentials. Otherwise, it would have little to no use. An air compressor would be a possible, but there you'd need to figure out the ps setup. No adapter that I know of that fits the stock pump to one of those. There you'd use a different ps pump and remote reservoir. Those type pumps are usually higher pressure since they came on medium duty trucks but they can usually be adjusted to work with the hydroboost system. There were single and twin cylinder compressors and they were even on P pump engines. Here's a photo of a twin on a 4bt with the VE injection pump. Like I said, they came on P pumps too. One note, those puppies aren't light because they are cast iron, not aluminum. Would require a bit of research for your engine to get the correct mount and braces to support that pump.
Crap... kinda figured there would be few uses for that vacuum pump. Ah well it'll be an interesting experiment until I get to the future brake & steering upgrades.

Good grief that's a big air pump! The p-pump might get jealous. I figure if I dig into an air pump install then fabricating/machining mounts will almost be a given.
 

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Discussion Starter #471 (Edited)
Now that the pedal's in I started laying out the southbend master/slave kit & working out what to do with the master cylinder's pushrod. I carefully slid off the preload strap on the slave's pushrod so that I could measure the throw within the master cylinder:


Before I started poking thru the pedalbox I put everything back in place & made some marks for interference checks (the big arc drawn on is the brake booster's diameter). The new master has a rounded-corner square shape so that you can just push into the hole & twist to lock it in. I hogged out the middle & chipped away at it with a variety of chisels to get the fit nice & tight:


Mounted! Next up is building myself a custom adjustable pushrod to fit this new setup. I'll saw the supplied pushrod in half & come up with a way to attach something from the handful of rod-ends I picked up:
 

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Yeah, that twin cylinder air pump ain't a small thing. Those were mostly on 6bt and 6ct engines but as you see in the photo some 4bts got them. Those were Bendix Tu-Flo 550 or Tu-Flo 750 units and the bare compressor weighs 53 lbs. Probably overkill on a 4bt unless you need a lot of air. Primary use was air brakes or air suspension. Another possible use for the vacuum pump I failed to mention was the exhaust brake system. When Dodge offered the exhaust brake the gear driven pumps were no longer used and a belt driven unit replaced it.
 

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Discussion Starter #473
Yeah, that twin cylinder air pump ain't a small thing. Those were mostly on 6bt and 6ct engines but as you see in the photo some 4bts got them. Those were Bendix Tu-Flo 550 or Tu-Flo 750 units and the bare compressor weighs 53 lbs. Probably overkill on a 4bt unless you need a lot of air. Primary use was air brakes or air suspension. Another possible use for the vacuum pump I failed to mention was the exhaust brake system. When Dodge offered the exhaust brake the gear driven pumps were no longer used and a belt driven unit replaced it.
Twin hole pump would be overkill for sure, at least for my plans with this build. I would love an exhaust brake, and I have a ton of room under the turbo where I could plumb one in, but I think you can get them in both negative/positive pressure control.

I put together a few different sizes of pushrods to mock up & took what I swear was hours of measurements before deciding on my new pushrod's length/design. The heavy duty Dodge trucks clearly had a much larger throw in their clutch pedal setup, which means I have much less space to work with in my Rover pedalbox using this master cylinder. Thankfully I can still manage to eek out roughly an inch worth of adjustment in my new pushrod before anything would run into the master cylinder:


Starting with a pile of parts helped a bunch in getting the new pushrod design right. In this case I have the last inch of original Dodge pushrod welded to a strong 1/4-28 bolt, with a jam nut locking it in place to the 1/4" teflon-lined rod-end:


The hole I made in the pedalbox was off by about an 1/8" from the pedal's lever, so just to be safe I cut a chamfer in it to prevent possible fouling. I'd prefer it be near perfect straight, & if I got creative I could grind out a little from the pedal to straighten it further. But it doesn't rub & moves smoothly throughout the entire travel. I do have to say my work on that spring down there sure is ugly... does the trick though! Anyway, I ground down the original brake pedal pivot-pin flush on both sides & drilled a hole through for the bolt. In general I try to avoid single-shear things, so if I see any signs of accelerated wear I may weld an angle on the lever to double-shear that bolt in the rod end:


This side of the engine bay is looking ten times better now! Glad I caught that rust while it was just surface deep. All new bolts & nuts are in, steering column is back on, throttle cable back in place. (Brake booster & master is in too, just waiting on final clutch hose routing before I call that finalized.)


Once I decide on a proper place for the clutch fluid reservoir I can button this all back up, & I should be getting my driveshafts back tomorrow as well!
 

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The Dodge factory optional exhaust brake was offered on '03-07.5 trucks with manual transmission and I believe '06-07.5 automatics. Those units came from Jacobs and they all were vacuum operated. The primary downside of those were the belt driven vacuum pumps had a bad failure rate. It was later discovered and corrected that the issue had been the size of the pulley being used. When they went to a slightly larger pulley the failures stopped. In the aftermarket, I believe all those use a pressurized system instead of vacuum. One thing to keep in mind should you decide on using one of those braking system is you must install the HD valve springs on the engine, at least on the exhaust side. One downside of all those systems is cost. They Jacobs units are designed for the 3.5-4" exhaust pipe so it would take some type of adapter to use it on an HX30W which only has a 2.5" outlet. They aren't cheap either unless you could find a used one. Those seem to be kind of scarce anymore unless you could find a Dodge dealer with one sitting on the shelf they want to get rid of.
 

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Discussion Starter #475
The Dodge factory optional exhaust brake was offered on '03-07.5 trucks with manual transmission and I believe '06-07.5 automatics. Those units came from Jacobs and they all were vacuum operated. The primary downside of those were the belt driven vacuum pumps had a bad failure rate. It was later discovered and corrected that the issue had been the size of the pulley being used. When they went to a slightly larger pulley the failures stopped. In the aftermarket, I believe all those use a pressurized system instead of vacuum. One thing to keep in mind should you decide on using one of those braking system is you must install the HD valve springs on the engine, at least on the exhaust side. One downside of all those systems is cost. They Jacobs units are designed for the 3.5-4" exhaust pipe so it would take some type of adapter to use it on an HX30W which only has a 2.5" outlet. They aren't cheap either unless you could find a used one. Those seem to be kind of scarce anymore unless you could find a Dodge dealer with one sitting on the shelf they want to get rid of.
Yeah they sure can get pricey! I have the 60lb springs already installed to deal with the 4k governor springs I put in the pump. It's not something I'll do right away if I do, but nice to know I have enough space... unless I utilize that space for compounds :lol:
 

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Discussion Starter #476
A few drops of thread locker on bolts that don't protrude into the bell housing & the new slave cylinder is in! I made sure to refit the little retainer on the pushrod inside, which is meant to set the initial preload (between the slave's pushrod & clutch release fork) & make installation considerably less annoying:


The hose had several points where it could rub on things so it received a couple of p-clips to keep it right where I want it. And now that there are 4 different size hoses running down thru that opening (right above the driver's side frame rail) I think it might be time to come up with some sort of plastic/aluminum block to clamp them all together vs 4 separate clamps like I have now:


All the firewall components (brake booster/master/lines, catch can, fuel lines, starter cable) are latched on again & the clutch master cylinder is in it's final resting place. I poked 2 holes in the tray & popped in stainless rivet-nuts to hold the clutch's fluid reservoir directly above the master. If it ends up a little too close to the hood where the seal runs along that edge I can always move it over to the inner fender, since the hose has length meant for a great big Dodge truck:


A stateside Discovery with a proper 3-pedal setup! Made me so happy to hop up in the seat & put boots on this new setup... my other projects might collect dust a while after this is on the road.
 

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Discussion Starter #479
Great video. Love that check list on the windshield.
Thanks! Just knocked another off that check list ✔

FINALLY got the driveshafts back. Both now the same lengths and same flanges, so now the front & rear are identical copies:


Front shaft is in, although I had to ditch that front crossmember for now (mounts to that pad on the frame with the 4 bolts stuck in) until I can modify it with a loop or something. Seems the consensus view on that particular crossmember is that it's not needed, but I mean it must've been in there for something... I would think?


Rear shaft in as well, no problems. I'm using all new hardware throughout, & even if grade-8 isn't needed I do prefer that yellow-zinc coating they typically come with that's much better at resisting corrosion versus the usual zinc coatings:


It's a pretty tight fit getting the modified Crx brake rotor (for my e-brake) in there between the transfer case's rear output flange & my custom divorced case subframe... but it's in & ready for the mechanical caliper mount I have in mind to fabricate:
 
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