383 HP engine I.D. ?

[70SunFun]

I have a 1970 Challenger R/T with a 383 engine currently in it. I have two questions. 1. The cast date code is 8-28-69 (1970 model year engine) and there are no stampings on the machined boss by the distributor so is this a warranty replacement block? 2. Do all 383 HP engines have the "letter-year 383", "HP", and date stampings on that machined boss? This engine has the last 8 digits of the VIN of the car stamped on the pan rail but I'm almost positive that it isn't numbers matching. Thanks!

 

[moparleo]

Moparts on the Web - Main Index

 

[70SunFun]

Moparts on the Web - Main Index

Thank you!

 

[DetMatt1]

Is the vin stamp just hard to read?

 

[70SunFun]

Is the vin stamp just hard to read?

No, it's very easy to read and looks factory. But, my car's scheduled build date was 219 and the engine casting date is late August 1969. That's almost six months in between cast date and car build date so I doubt that it's the original engine. Plus there's no stampings on the machined boss by the distributor. I believe that boss should read: F383 HP (and whatever date that the engine was assembled). Thanks!

 

[Xcudame]

If the engine block was machined and the cylinder surfaces decked, it would remove the F383 HP and any other numbers on there as the pad is the same surface as the cylinder head.

With the massed produced 383, odds are not in your favor of it being original to your car as about 120 days max is what to expect from block casting, engine built and put in the car. But weirder things are known to happen.

Warranty blocks normally have special metal tags attached to them.

 

[EV2RTSE]

My numbers matching 383HP block was cast 7-10-69 and the car was built in late March of 1970. Agree your block was possibly decked so the pad numbers were wiped out.

 

[Xcudame]

EV2RTSE, thanks for providing an example of a numbers matching engine that was cast earlier than 120 days of build date. I know they're not common, but do exist. Some number matching hemi cars the block was casted over 12 months prior!

Personally, in the case of number matching 383 and 400 cars, I think it would be OK to restamp a decked block. Others may have other opinions.

 

[70SunFun]

If the engine block was machined and the cylinder surfaces decked, it would remove the F383 HP and any other numbers on there as the pad is the same surface as the cylinder head.

With the massed produced 383, odds are not in your favor of it being original to your car as about 120 days max is what to expect from block casting, engine built and put in the car. But weirder things are known to happen.

Warranty blocks normally have special metal tags attached to them.

Excellent information and thank you!

 

[70SunFun]

My numbers matching 383HP block was cast 7-10-69 and the car was built in late March of 1970. Agree your block was possibly decked so the pad numbers were wiped out.

View attachment 114433

Hmm, that's encouraging. Thank you!

 

[413]

EV2RTSE, thanks for providing an example of a numbers matching engine that was cast earlier than 120 days of build date. I know they're not common, but do exist. Some number matching hemi cars the block was casted over 12 months prior!

Personally, in the case of number matching 383 and 400 cars, I think it would be OK to restamp a decked block. Others may have other opinions.

It’s not OK to restamp anything, what are you trying to accomplish with your stamps? It’s not factory anymore, it’s your creation.

 

[Xcudame]

Not restamping the vin on the block near the oil pan rail obviously. But when you deck the passenger cylinder head surface on a B block, it will likely remove the year letter and engine size (i. e. G383) plus any other stampings on there. If you restamped it, you would retain your original information. And like I said, others may have different opinions. I doubt there are many as built by the factory running out there.