1972 400CI motor

VSO737

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Hi,
I'm new to this "C" bodies site. The reason I joined is because my 1969 RR has a 1972 400CI motor that if my research is correct, came in a "C" body vehicle.

Can anyone help me ID the motor:

CASTING#: 3614230-4
ENGINE ID#: 2C208217
PAD STAMP#: 17782 A

Thank you in advance,
LG,
Mike

P1090163- PAT69RR.jpg
 
Well the casting number is definitely 71-72 400CID. Others will chime in with the rest. Nice RR!
 
The 400 replaced the 383 for the 72 and later model years.
It was available on C & B bodies.
 
YES, I realize it is the MOPAR motor with the biggest bored cylinders. Internally it is the same as the 383CI.
I believe the 400CI went from 1972 to 1974. Not positive on that...…….
I took a nice picture of a 1972 RR with the 400CI motor. I noticed that his breather hose was at a different location than my motor.

I was also informed that the "C" in my engine ID# 2C208217 stands for the Jefferson Plant which ONLY built "C" MOPARS.

I have confirmed it is a 1972 as stated here and also that this BLOCK is the one to use to build a stroker due to its beefy/heavy duty composition.

Thanks again,
LG,
MIKE
Picture of the '72 RR...………..

P1110931.JPG
 
What numbers/letters are on pad in front of the passenger side head? Read left to right top to bottom standing looking over the pass fender.
400 was made until, 78-79.
 
What numbers/letters are on pad in front of the passenger side head? Read left to right top to bottom standing looking over the pass fender.
400 was made until, 78-79.

After I wrote '74 I knew it did not sound correct...…………..
I wrote these numbers a while back when I had the Hooker headers off to get ceramic coated. I took advantage of the situation and wrote down all the numbers I could off the block. I had NO IDEA it was NOT a 383CI motor. Now, I wonder if the guy who sold me the car knew it was a 400CI. The motor had ONLY approx. 2K miles after being rebuild when I purchased the car.

I'm pretty sure these PAD numbers are from the passenger side near the distributor. I'll be under the car tomorrow installing a mini starter. I will confirm these numbers then.
PAD #: 17782 A

I would LOVE to know what "C" MOPAR this motor came off of.

Thanks again,
LG,
Mike

HOOKER HEADERS COATED- 017.jpg
 
Not sure why the real concern about the 400 and its model year? Reason is that they were ALL 8.2 CR, had the later (slightly different from prior 383s) cam, and generally considered an "emissions motor" (and therefore "not worth messing with" by many). The 400 is also generally limited to a .030" overbore, due to the later thin-wall castings, which generally means ONE overbore with a rebuild operation. From a worn factory bore, it usually takes that much of a cut to get to "clean metal" for a round bore diameter, by observation.

As for the "stroker" orientation, cut the mains on a 440 crank down tro 383//400 size and "instant stroker" to about 452cid. Reuse the factory pistons and rods, but rebalance them?

The bore on the 400 is larger than that of the 440, but with the shorter "383-length" stroke, which is where the additional 12cid comes from. 12 cid that could probably be compensated for by a slight bit more cam duration/lift without all of the time/./expense of the stroker situation, it seems to me. BUT I know that some people like these things. Is a neat way to get more inches from a low-block B engine, though, without having to change the external things like intake manifolds and such.

With the longer stroke, some of the 383/400s ability to "zing" might be diminished due to the lower rod ratio. As the Chrysler 383/400 shares the same rod ratio as the 302 Chevy small block, which was noted for its higher-rpm capabilities, IF that matters. Just as the 383 shares the same bore/stroke ratio with the 302, also. NOT a bad deal, but just takes a little more finesse to make the motors work as well as they can, by observation.

So the B motor is more "rpm oriented" as the RB (longer stroke) is more "torque oriented", by comparison, in the basic design (rod ratio).

End result, the 400 can have the same performance capabilities as a 383 did. The 4bbl HO engines still had the windage trays and other internal upgrades as the 383//335 motor had, all the way to the end of production (according to the Dealer Order Guide), but with the 8.2CR for emissions purposes. 400 automatics should have had cast cranks, although the 400HO 4-speed cars had steel cranks. NOT a big deal for a reasonably stock power Chrysler engine, or even one with some performance items either. Main difference is the balancer/flywheel/torque converter matching of this situation, just as on other brands of engines where some used a cast crank and others used a steel crank.

So, build your 400 with some "quench dome" pistons to get the CR back up into the middle 9-range. Use a 383 RR spec cam, or a little better. Clean up the head ports (stock valve sizes are fine), and enjoy!

CBODY67
 
The reason I want to know what car my motor came off of is so when I purchase replacement parts, I have a better feeling of what to order. The days of going to a parts counter and ordering old school is long over. Now, the FIRST thing out of the parts counter sales person is "what year and model". Everything is on their computer.

So far, I know that my 400CI motor came in a "C" body 1972 MOPAR. I also know that the 3614230-4 block I have is the heavier duty block with the thicker webbing. Hence, the preferable one to make a strocker out of.
What I don't know is, ¿ Did all 1972 MOPAR 400CI cars have this 3614230-4 block?

Do I understand the PAD STAMP correctly...…….my number is 17782 A. That the "A" signifies BIGGER BORE size.
I need to learn how to DECODE the engine pad numbers, 17782 A

I doubt I will ever mess with my motor. The motor has less than 4K miles on a complete rebuild. I made a HIGHWAY cruiser out of it and it is STILL FAST...………….I DO NOT race it and it is strictly a car show DRIVER.

Attached is a picture of what was done by the previous owner.

Engine SPECS.jpg
 
Except for pistons all the parts for a 383 will interchange with a 400.
The tin will be different between the 2 but you would want that to be 69 correct looking for show duty.
 
My two cents...

You have a 400 block with a forged crank. If it was out of a C-body, it wouldn't surprise me if it was a cop car because of the forged crank as I think most of the passenger cars had cast cranks. But, it really doesn't matter squat about what car it came from as they were all alike.

Looking at your car, you have a Holley carb, Edelbrock manifold, Hooker headers, most likely some sort of upgraded electronic ignition, aluminum radiator etc.

Walking into a parts counter isn't going to be easy for you. It's all non stock parts... Let's give an example... You need plug wires. Well, OK, you have headers so a stock set isn't going to fit. Now you are looking at a generic wire set. Need plugs? Unscrew one and get the part number because after all those mods, the stock heat range for a '72 Fury or a '69 Roadrunner might not work with whatever the entire combination is.

The only time that the 400 block is going to come into play is if you need a crank, rods or pistons. All the rest is interchangeable with '69 383 stuff. The bolt ons are going to be what determines what you buy for your car, not the 400 block.

Of course, what do I know?
 
My two cents...

You have a 400 block with a forged crank. If it was out of a C-body, it wouldn't surprise me if it was a cop car because of the forged crank as I think most of the passenger cars had cast cranks. But, it really doesn't matter squat about what car it came from as they were all alike.

Looking at your car, you have a Holley carb, Edelbrock manifold, Hooker headers, most likely some sort of upgraded electronic ignition, aluminum radiator etc.

Walking into a parts counter isn't going to be easy for you. It's all non stock parts... Let's give an example... You need plug wires. Well, OK, you have headers so a stock set isn't going to fit. Now you are looking at a generic wire set. Need plugs? Unscrew one and get the part number because after all those mods, the stock heat range for a '72 Fury or a '69 Roadrunner might not work with whatever the entire combination is.

The only time that the 400 block is going to come into play is if you need a crank, rods or pistons. All the rest is interchangeable with '69 383 stuff. The bolt ons are going to be what determines what you buy for your car, not the 400 block.

Of course, what do I know?

Great advise. I guess now my main reason is just curiosity. I'd just like to know what car it came off of...….no real reason to really know since it will not make any real difference not knowing.
Funny you mentioned the plugs. I was just thinking about that last night, to write down the specs on them since I have the LH all out due to being in the process of replacing my starter with a PWM mini starter. I have to remove the header and starter as a unit to get the starter out.

The guy who built this car put the MSD box on the cab side of the firewall. The battery and remote solenoid behind the seat all hidden.
I'm NOT in restoring to original specs. "Been there, done that" with my 1957 Corvette NCRS "Top Flight" restoration.
I've been wanting a 1969 RR since 1969 and now that I have my 'dream car', I'll NEVER part with it. Nor my Model A that took me 5 years and 6 months to build in my two car garage.

Thanks again for all the great advise and information.

LG,
Mike
 
Pictures of model A?

I put a 400 in place of my original 383 to preserve it.

I hear yah. I don't plan on ever selling my ride but who knows what my family will do with it after I'm gone. My 16-year-old grandson already told me he has 'first dibs' if I ever want to sell it.
That is why I don't get rid of anything that came with the car even though I don't use it, i.e., ashtray. I don't allow any smoking near me let alone in my ride. Besides, I made a holder and placed two gauges where the astray goes.
I also kept my 3:95 to 1 ring and pinion when I converted to the 2:65 to 1. Now I cruise at around 65 doing 2100 RPM.

I just installed the PWM mini starter and noticed that the NUMBERS 17782 A were taken from the very bottom of the block. They face the ground and near the flex plate.
I will see if I can locate the PAD numbers near the distributor.

Again, thanks for all the info...………….never learn too much.

LG,
Mike
 
Having been in the dealership parts business for over 40 years, I have taken calls of people who wanted to know what a particular stamp code (GM, in this case) fits. If it's a Corvette block or one from an Impala, for example. Or an L82 Corvette block. Or maybe a '69 Z/28 302? Certainly, they have the same concerns about buying parts for rebuilds. Only thing is, as far as parts go, a 4" bore Chevy small block casting is just that. If the '69 Z/28 302 block has been decked, then that wipes off those $$$ stamp codes, making it just another 4" bore Chevy small block casting. Common bearing sizes, etc. So the casting is the same, but it's what's inside of it that makes the difference. Over the years, there were some variations in the castings, but nothing which would really affect the rebuild parts.

One time, our parts manager didn't want us giving out that information, or taking the time to look it up (which we did in slack time anyway). But when I tried to explain that a '79 Corvette 350 block was the same, regardless of whether the L82 or LM1, I took MORE time to do that than it would have taken to look it up in the first place. But there's those "bragging rights", too!

Use the block casting numbers for model year ID, plus to ensure the engine size. Past that, a 400 is a 400. The HO models got the hotter cam and upgraded bearings, plus some other internal items, whereas the normal 400 got the normal "used to be 383 2bbl" stuff. ALL good OEM stuff, just that some like the thought of it being "HO" or "HP".

The main thing about the 400 is its lower 8.2 compression ratio. Easy to help with a pair of closed chamber heads from an earlier 383, just might need to add the 1.74" exhaust valves (which the 400s had anyway). Seeking out a quality head gasket that is more like .040" compressed thickness rather than .060" compressed thickness can help, too.

As for the information for the computerized parts person at the auto supply, just tell them 1972 Plymouth Road Runner, which could come with a 400cid 4bbl V-8. THAT will get you what you need. But you'll need to find some pistons with a bit higher compression ratio, for best results. What model year application you choose will also depend upon which heads you use . . . closed chamber or the open chambers (like came on it).

ARE there any reputable drag race (for example) engine builders in your region that could talk you through these things, making you a package deal for the parts and rebuild? Especially one that does MOPAR engines!

Just some thoughts,
CBODY67
 
that 400 can be stroked n bored to 500 plus inches . check 440 source . and there are many other engine kits out there . you could just rb crank it , 451 without a bore job .
 
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