Engine confusion may need decode

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Have a 71 dodge that originally had 2 barrel 383 which should be externally balanced. Engine replaced with remanned assumed 4 barrel 383 engine in the year 2003. Casting on engine reads
11.16.66
246813012
LL

Does this engine have internal balance or external balance?
 
The car does seem to vibrate to much and spark knocks with cheaper gas like 91 opposed to 93 have external balanced harmonic balancer and torque convertor. Is it internal balanced with forged crank? What is the compression ratio?
 
Have a 71 dodge that originally had 2 barrel 383 which should be externally balanced. Engine replaced with remanned assumed 4 barrel 383 engine in the year 2003. Casting on engine reads
11.16.66
246813012
LL

Does this engine have internal balance or external balance?

2468130, the last two digits are not part of the casting number. This is a 383 B block casting number and all 383 engines of this type were internally balanced. That casting date is a '67 model year engine. 2BBL and 4BBL engines both use the same casting number. The '72 and later 400 engines were externally balanced. You do not want an externally balanced convertor or harmonic balancer on any internally balanced engine. If it is vibrating and you have those components installed you need to acquire the proper convertor and harmonic balancer or you will destroy the engine. The '67 2BBL engine was a 9.2-1 compression ratio, the 4BBL engine was a 10-1 compression ratio. If you ordered a stock 4BBL engine, most likely it will have the 10-1 ratio and the higher performance camshaft. If you have access to a bore scope, the lower compression ratio was accomplished with dished pistons which should be easy to see. The 10-1 ratio will be flat tops.

Dave
 
Info much appreciated. What about the one exeption that the 1971 383 2bbl was a cast crank external balance engine and the 1971 4bbl was forged crank internal. The engine was in fact remanufactured so is it possible that could be an external balance motor?
 
TMI.
It doesn't make a hoot what the block is.
Steel crank, internally balanced
Cast crank, externally balanced.
 
Info much appreciated. What about the one exeption that the 1971 383 2bbl was a cast crank external balance engine and the 1971 4bbl was forged crank internal. The engine was in fact remanufactured so is it possible that could be an external balance motor?

I would not expect to find that (cast) crank installed in a '67 motor, but you never know. As you appear to be having engine balance issues, my best guess is you do not have a cast crank. You might want to pull the pan and check the shaft number. 2268114 is the number on the more common steel crank. 3462923 was the number that was used on some of the '71 engines.

Dave
 
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Any way to tell exept pull oil pan and examine the crank?

Pulling the pan would be the best and sure way. Rebuilders usually try to match components to the same year engine so the this type of problem does not occur. Did you specify a '71 motor when you ordered or just a 383? There were not a lot of cast crank 383 engines even in '71. If you ordered a 4BBL engine, it would have the steel crank as the cast crank was only used on 2BBL engines and not even all of them.

Dave
 
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I dont remember. I bought it with a blown 383 2bbl. Put a used 78 cordoba 400 in it then the current engine so i must have told them 383 4barrel. It still runs and drives not too bad.
 
Pulling the pan would be the best and sure way. Rebuilders usually try to match components to the same year engine so the this type of problem does not occur. Did you specify a '71 motor when you ordered or just a 383? There were not a lot of cast crank 383 engines even in '71.

Dave
They were all steel. The confusion comes from some were not drilled for the 4 Spd pilot hole. Previously all were.
 
They were all steel. The confusion comes from some were not drilled for the 4 Spd pilot hole. Previously all were.

The 3462923 part number shows as 383/400 starting late '71, not common for 383 2BBL but still out there. ( Typo corrected, crank was listed as 4362922)

Dave
 
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Thae car was built in 1970. As far as vibration I could not tell the difference at the time. I may have put the external balance 400 engine in with a internal balance torque convertor. Back then I was young and had mechanics do it so now it I must identify everything.
 
Thae car was built in 1970. As far as vibration I could not tell the difference at the time. I may have put the external balance 400 engine in with a internal balance torque convertor. Back then I was young and had mechanics do it so now it I must identify everything.

Excellent place to start. If you used the 400 balancer when you put the 383 in, that might be all you need to change.

Dave
 
Well. Looks like the oil pan has to come off for inspection. Must be a pretty good engine if it made it about 30000 miles unbalanced.
 
Im positive the torque converter is for external balance. The original harmonic balancer I still have has no weights. The one that is on can not tell right now as its burried by the other pullys.
 
Im positive the torque converter is for external balance. The original harmonic balancer I still have has no weights. The one that is on can not tell right now as its burried by the other pullys.


The externally balanced convertor has some weights welded on to the bell of the convertor, the internally balanced convertor has none. The 400 balancer has a cutout portion for about 1/2 the circumference of the inner radius where the timing marks are, it is easy to spot. The 383 internally balanced harmonic balancer is a smooth circumference with no cutouts. There are no weights on either balancer, the 400 used the cutout for that purpose. 400 balancer part no is 3614374, for the iron crank. 383 cast crank 3577180. To further confuse the issue, there is a 400 with a forged steel crank (72-73) balancer part number 2268114.

Dave.
 
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