Topic: 428 C block??

[JamesM]

Hello all.
I have a standard bore block with the C scratch and 428 in the water jacket. There is a 352 with 46 below it, also there are a series of numbers on a flat smooth area, they read OZ611788. A collector/restorer of FORD's told me it was a CJ block from April 1970. Any information on what the OZ numbers mean would be appreciated.

[Coralsnake]

O is the year (thats a derivative serial number)

Z is the plant code for St Louis, Mo ( not a Mustang plant )

Could have been a full sized Ford block, they share the same physical features.


352 is a series number only with 46 being the mold number.

Unfortunately, even if it were Mustang, it would appeal to a very small number of cars.

[JamesM]

Knowledge makes life so much easier. Thank you for solving this for me. This engine was one of 3 that came with the car, thankfully the correct one was in the pile...

[69cobrajetrugae2]

What are the numbers by the oil filter adaptor?

Check for core shift in the lifter bores. I am suspicious of standard bore blocks as it's possible that the block was a cam eater thus never got used much. 428CJ engines are not known for this defect as the 455 GM blocks are though.

[sah62]

A collector/restorer of FORD's told me it was a CJ block from April 1970.

It would be more correct to call it a "reinforced 428 block" that was used with the 428 CJ. There is no block that was unique to the 428 CJ. Once the reinforced block was introduced it was used for non-CJ 428 applications, too.

[JamesM]

There is a tag with "W" and another tag below that with a O that has two dots under it then D9. Not a very scientific way I measured the bore, took a stock CJ piston and fit it into the bore (no rings). It was tight. I'll research and figure out what the other question was. My friend from whom I finally bought the car off of (trying since August 1985) was a scavenger. He had 4 cams, thinking I was really lucky he then told me they came off irrigation pumps....those were left
 in Texas.

[JamesM]

Looking at the block as it sits vertical, the cam does look off a few thousands (from side to side, top to bottom is centered), the lifter bores are dead centered. Above the dipstick hole is 37 DIF. I was guessing the OZ611788 was a partial VIN, loosing that feeling every second. Now getting the feeling this one sat in a field pumping water for a few years.

[sportyworty]

0D9 represents April 9th 1970
The block was cast on the West line as opposed to East
Your block was initially installed in a 1970 full size Galaxie or Meteor produced at the St. Louis plant.
Very good chance it is a true PI being a 1970. They were installing 429 2V as well in the same chassis. The last full size 428 production were almost always P code fleet cars like police/taxi
Regardless the blocks in bare form are the same. Differences in block features are date related not car model. The block improved since its introduction for 1966. By the time the CJ was introduced the 428 had evolved to a triple web with C scratch designation as opposed to early versions with out web and A scratch. There are exceptions but they are extremely rare.

[Raven R Code]

Not sure if this one point was made clear.....a "C" scratched in the back of your 428CJ means it was designated for mustangs. Different car lines had different letters.

[sah62]

Not sure if this one point was made clear.....a "C" scratched in the back of your 428CJ means it was designated for mustangs. Different car lines had different letters.

I don't think this is true. We've done a lot of research as part of the 428 Cobra Jet registry project and we still haven't found a definitive source of information to translate mold marks like the "C" scratch. Remember that the 428 CJ was also used in Torinos and Fairlanes (a different car line (B) completely), but the blocks used for their engines were also marked with a "C". The 428s used in full-sized cars (again different car lines) during the 428 CJ time period also used the same reinforced block.

[RoyceP]

What you are saying was an urban legend popular 15 - 20 years ago. Through the magic of collective knowledge and the advent of internet communications, it was debunked long ago. The C scratch started to appear on every 428 block around the fall of 1967, whether it was intended for a Mustang, Cougar, Fairlane, Torino, or granny's 428-4V powered Parklane station wagon.

Not sure if this one point was made clear.....a "C" scratched in the back of your 428CJ means it was designated for mustangs. Different car lines had different letters.

[Bob Gaines]

What you are saying was an urban legend popular 15 - 20 years ago. Through the magic of collective knowledge and the advent of internet communications, it was debunked long ago. The C scratch started to appear on every 428 block around the fall of 1967, whether it was intended for a Mustang, Cougar, Fairlane, Torino, or granny's 428-4V powered Parklane station wagon.

428 station wagons used to be a great source for 3 web blocks (CJ) . Now the station wagons are like hens teeth to find.

[sportyworty]

There are still quite a few 4 doors left out here in California on Craigslist. Still treasure out there between San Diego and Sacramento. I have been hunting and parting out full size P and Q code 68 cars for a couple of decades now. Picking up an April built Merc Parklane 2 door hardtop on Wednesday. It will have a great C scratch block, and 15x6 steel Shelby wheels and bonus being a mid year still has the starter delay relay. The P code also had either the c7 PI intake or the Cast CJ if built after March. This one runs and is loaded so likely refrain from parting for awhile.
I have never seen a vehicle production era 428 CJ with any scratch different than the "C"
The post 1970 428 blocks had some different scratches like CX C1. These were service and industrial applications. The pre CJ era was "A" and a limited run of "S" cast Dec 66-Jan 67 with cross bolt bosses.
I have never seen anything with more mystery and misinformation perpetuated than the FE.
Scott's website 428 reg has the most current accurate info as we know it today.

[Mark69Sportsroof]

Interesting subject.  I have a 1968 Mercury Park lane convertible.  It was built in Apr 68 at the St Louis plant.  It still has the number matching 428-4V and C-6 tranny.  Where would these markings normally be on the engine?

Thanks Mark 

[sportyworty]

Hi Mark

The "scratch" marks referenced are on the rear face of the cylinder block. The "C" version found on blocks cast June 67 and later can be found on either side of the block or reversed/inverted. Many are irregular versions of a letter C to appear almost as a letter U or V even.
This is the latest update on the 428 blocks used in cars built 68-70 with some mention of others
https://www.428cobrajet.org/id-block

Kerry