Introducing a 1970 300 TNT convertible

That's odd.....I used the GAT 20630 (with my Spectra CU332) and it fit perfectly. Lower was Dayco 70592, BTW.
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You could probably use a reproduction '70 B-body 26in rad hose set on the car. I know the C-body 22in rad hoses are the same as B-bodys.
 
@david hill has continued going through the engine bay. As I posted earlier this month, we are redoing the engine cooling and to that effect I bought a Gates 42032 water pump, Cloyes C-3044 double-row timing set, and Fel-Pro TCS124602 timing cover gasket set. Last night, I also ordered new Mancini Racing 44082 heater hose nipples as I had for Medina.

The car's timing chain was not original (it was metal, see pics below) but it was very worn out. From disassembly, David figured out that things had been opened up once before -- ultra black sealer having been used at the base of the timing cover, as well as steel-reinforced foil pan gaskets having been installed. Not available in 1970 for either.

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Good news -- David just told me the "engine came apart very clean inside considering the mileage involved." So far, so good!
 
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@david hill is making great progress on the TNT, and here is what he told me last night: "started and had the engine running today. Came up to operating temperature and ran exceptionally well. Overall engine condition is very very good. The carburetor is working exactly as I expected it to."
:thankyou:

Now that the car runs, the next thing is the brakes. The front brakes are leaking fluid, so David was not able to drive it yesterday. It looks like a new master cylinder is needed (the booster seems fine). The front rotors are really thin, too, so I just ordered two Raybestos 7012R (7012L are not available anywhere, so David has told me that he'd deal with the left-directional studs) and matching PGD39 Element3 pads from Rock Auto -- see this thread for discussions of choices. The brake lines all looked really good to David, but I will be replacing the brake hoses with new Raybestos Element3 brake hydraulic hoses -- one BH36651 rear center and two BH35017 fronts.

On the wish list are tie rod ends (inner and outer, and sleeve) and also a fan shroud. Luckily, @70 Sport Suburban had a correct used one (P/N 2785435 fan shroud for a 26” radiator) that he agreed to sell to me —it will be transferred to David and me at the C-body show organized by @sixpkrt in Union, IL this Saturday. Things are moving along!
 
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Latest update is the installation of new front brake rotors Raybestos part #7012R. Fit like a charm rotor dimension are spot on. Master cylinder and brake hoses are next. There been questions on fitment as the photos below show, a perfect fit. The fan shroud was a bit difficult, once installed fan clutch oper. was spot on.

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Thanks for the update David.

I am glad they seem to meet your specs. They, however, do not appear to be the two piece rotors, rather they look just like the one piece Centric rotors. Did the boxes indicate where they were made?

While some tout the old nos rotors as superior to the "Chineseum" ones, the Centric rotors are advertsied as having a high carbon steel content. This makes them much stronger and more wear resistant than the mild steel that was used in the original heavy two piece ones made 50 years ago so they don't have to be two piece very heavy outdated designs to be strong. I am very happy with the Centric rotors on my cars and no one has commented that they do not look original yet probably because they are hidden from view pretty well :rolleyes:.

I don't mind not having to pay a heavy premium price for heavy rotors that aren't as strong/wear resistant as the ones available now and the new ones are apparently well-made to strict tolerances from what we see from David's measurements and can't be seen readily anyway when on the car. They also brake just fine with the new materials including non-asbestos pads that turn your wheels black, needing frequent cleaning. Since the new rotors are less bulky they don't store as much heat and they dissipate it much more quickly as a result too. That is a big plus on long steep downgrades where braking can be more of a challenge on our older heavy cars.
 
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Here is the conclusion to the brake restoration. Both brake calipers were in dire need of rebuilding. Photo's below show the evidence of rust build up from long time storage. As many of you may have experienced seal kits and caliper hardware are the only parts listed for C bodies. Upon further investigation I found that 1973 Dodge Challenger brake calipers use the same caliper piston 2.75. Hardware is exactly the same as the 70-73 C body brake calipers. At the time of the calipers rebuild no caliper pistons were available, however I was able to acquire a pr. of 1973 Challenger w/ the 400 eng. option. I completely disassembled the Challenger calipers and used the pistons, seals, dust boots, and hardware on 1970 300 caliper cores. Broken bleeder screw was removed w/ a blow torch, vise grips and a table candle. Not the easy way to do it. After bleeding brakes and a test drive. perfect front brake action was restored.

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Here is the conclusion to the brake restoration. Both brake calipers were in dire need of rebuilding. Photo's below show the evidence of rust build up from long time storage. As many of you may have experienced seal kits and caliper hardware are the only parts listed for C bodies. Upon further investigation I found that 1973 Dodge Challenger brake calipers use the same caliper piston 2.75. Hardware is exactly the same as the 70-73 C body brake calipers. At the time of the calipers rebuild no caliper pistons were available, however I was able to acquire a pr. of 1973 Challenger w/ the 400 eng. option. I completely disassembled the Challenger calipers and used the pistons, seals, dust boots, and hardware on 1970 300 caliper cores. Broken bleeder screw was removed w/ a blow torch, vise grips and a table candle. Not the easy way to do it. After bleeding brakes and a test drive. perfect front brake action was restored.

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Way-ta-go, David!! This is very valuable information.
 
The 1973 Challenger listing on the O'Reilly Auto Parts Shows a 400 2bbl option. Listing is Part# 18-4065 & 18-4066
Interesting... Goes to show you how accurate some of those listings are.

I looked at Rock Auto and they also listed 360 and 400 engines for the '73 Challenger! I think it's a moot point though. That is the caliper they list for all engines for that year.

RA does something that is pretty good and that is you can see what else that part number fits. I wouldn't take it as gospel, but if you can use some common sense and maybe compare Chrysler part numbers, it can get you where you need to be.

In this case, robbing the new parts from the rebuild to fix the old is brilliant.
 
Interesting... Goes to show you how accurate some of those listings are.

I looked at Rock Auto and they also listed 360 and 400 engines for the '73 Challenger! I think it's a moot point though. That is the caliper they list for all engines for that year.

RA does something that is pretty good and that is you can see what else that part number fits. I wouldn't take it as gospel, but if you can use some common sense and maybe compare Chrysler part numbers, it can get you where you need to be.

In this case, robbing the new parts from the rebuild to fix the old is brilliant.
In this case an old Motors Manual and a veneer caliper was I needed, plus having rebuilt several E Body calipers and remembered there bore size was 2.75 inches
 
Guess who's getting a new Mopar Performance voltage regulator and a new Stant 10230 radiator cap?

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I would have preferred a NOS or reproduction 3438150 regulator with the correct dimple, but the company that used to sell the correct date-coded/stamped repros is not doing that anymore. So I bought three Mopar Performance VRs (as recommended by @Dobalovr as ideal replacements for a 3438150) from Summit, as their prices were 30-50% of what I was finding online for the same items. Two had white fonts (Mopar 77R06285), one had a yellow-sticker (Mopar P4529794). My TNT had the exact same (replacement) regulator already, so I picked the yellow-font unit for her.

Where is the radiator cap going? Well, as noted earlier, @david hill took out the original high-efficiency 2998970 3-core radiator that was in the car, and he replaced it this summer with a Spectra CU332 radiator while I decided whether to re-core the original. He has a good shop to do the re-coring, so the original 2998 970 will go there. I can then decide whether to re-install it in the TNT or to keep the Spectra in this car and keep the original for another car. My preference would be for the former, but it'll depend on what the rest of my little fleet needs.
 
Yet another repair full of surprises. The MOPAR replacement voltage regulator was painted in a heavy coat of black. Were talking powder coat thick. A little fiber disk work took care of that. Reassembly and a quick restart reveals a higher than expected alternator amperage out put. Volt drop tests showed significant voltage drop loss between the battery and the main Bat splice for the alternator. The removed unions below accounted for a .574 volt drop over a 12" area next to the battery all repairs were soldered and shrink tube covered. See photos below. All is back to normal.

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Yet another repair full of surprises. The MOPAR replacement voltage regulator was painted in a heavy coat of black. Were talking powder coat thick. A little fiber disk work took care of that. Reassembly and a quick restart reveals a higher than expected alternator amperage out put. Volt drop tests showed significant voltage drop loss between the battery and the main Bat splice for the alternator. The removed unions below accounted for a .574 volt drop over a 12" area next to the battery all repairs were soldered and shrink tube covered. All is back to normal.
Don't you just LOVE surprises?

Similar situation for me. Old, crappy splices made the VR think the voltage was too low, so it "regulated" the alternator to crank out 16+ volts. As David did, solder and shrink tube (and correct repro cloth-like electrical tape) made for a nice mid-13s charging voltage.
 
Quick update on the TNT.

As a first fix to get the cooling going, I had bought (and @david hill had installed) a Spectra Premium CU332 radiator in the spring. The idea was to have a brand new radiator in the car so it could be driven, while we looked for a good shop to recore her original 2998970 radiator. David found the right person and dropped off the rad two weeks back. Good news, he got the 2998 970 radiator back yesterday. After painting, it will be reinstalled this coming week. The (now almost) new CU332 will replace, to improve cooling at rapid highway speeds, a similar unit in Buttercup, my 1972 NYB, whose radiator is not original anyways (it likely is an old CU332 -- looks like it).

David also will be installing new manifold cover gasket. I bought the last 1968-71 Big Block C-Body Exhaust Manifold
Fastener Kit (for HP BB 383 440 engines) from 521 Restorations on eBay to that effect:

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I also got from Summit three Mahle F5561K exhaust pipe flange gaskets, and a Fel-Pro MS90029 exhaust manifold gasket for U-code enginess
 
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