CJ or not CJ

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My car is a '72 and a CJ (according to the marti report) and has 4 bolt mains. It is the original engine.

Just thought I'd throw that in there. You never know with these cars lol.
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As stated, there were 4 bolt mains left over from the Boss run. As a result, you have the fortunate circumstance of getting a Boss block no charge.



Wow... someone had a lot of time on their hands. Thanks for clearing things up... :)
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Don't tell the wife.

There are a variety of outstanding people on this site. Everyone has their strengths and weaknesses. I like to see documentation...service manuals, owners manuals, drawings, spec manuals. I have posted a lot of pages to this site so people have the facts.

And, unfortunately, I pretty much want the facts to rule when it comes to the information on this site. When someone gives me the facts, like a guy is Original Owner of a 72 351 CJ and it came with 4 bolt mains, what am I supposed to do. However, if he is the 3rd owner of a car with undocumented mileage, I am going to stick with the service manual and the spec manual...

That being said, there is nothing documented that a 72 351 CJ has 4 bolt mains. Most have 2. Does anyone believe Ford randomly drilled extra holes in blocks and girdles for fun? The reasonable and most likely explanation is leftovers. Wish I had leftovers.

On the other hand, I have asked for and not yet even seen a Ford Service Manual detailing the tightening order for a 4 bolt main motor. There are plenty of 2 bolt main instructions. So, does that mean Ford never built a 4 bolt main 351? No. As far as I can tell there is only one little pre production pamphlet for the BOSS that indicates a 4 bolt main(at least I think it is in there).

But, people shouldn't get upset if there 351C 4V with or without CJ HO 4V or whatever doesn't have 4 bolt mains....unless they think they have a BOSS.

And a BOSS motor is easy enough to forge.

And...since I have the time, this is a great educational site. I am not always right, and have had to eat crow at least twice. But the facts were brought to light, giving us all the opportunity to be properly educated about our cars. The more we are educated, the more we can talk on the same level and get to the important stuff, like how best to make our cars loud and proud.

So, go get loud.

 
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And...since I have the time, this is a great educational site. I am not always right, and have had to eat crow at least twice. But the facts were brought to light, giving us all the opportunity to be properly educated about our cars. The more we are educated, the more we can talk on the same level and get to the important stuff, like how best to make our cars loud and proud.

So, go get loud.

I'm with you on that sentiment... After reading and researching our cars and what powers them I'm thinking that when they scrubbed the 429 after 71, that was the real end of the actual Cobra Jet engines.

My car is loud and I'm very proud to own it.

 
Wow...there is a lot of bad information in this thread. After my rant below are answers to your original questions...

As I recall, you wanted to be able to tell if a block was a CJ or not.

First, there is NO WAY to confirm the block is a CJ. You can discuss date codes on the block, and certainly 72 casting were put in 73 Mustangs....how else would a 73 Mustang bought in October of 73 have a engine. However, it is not outside of the realm of possibilities a 71 casting made it into a 73. And certainly, 73 castings were found in Mustangs. I had one. From the dealer. June 1973.

Second, regarding 4 bolt mains. I have torn apart 3 351C motors- 1971,1972, 1973. All were factory 4V motors. Zero had 4 bolt mains. As stated previously, I am unaware of any 4 bolt 351C motor except the Boss and a few stragglers in 1971. It is fairly easy and not uncommon to have builders add the bolts. But a 4 bolt main is no guarantee of a 351C CJ.

Third, in the 1973 Ford Service Manual and Specifications Manual(Both attached), you will find the following:

1. The SPECIFICATION MANUAL(Second and final printing) does not mention the HO. Only the CJ.

2. The Service Manual mentions the CJ once. In regards to the VIN. This is where the famous Q CODE designation is found. If someone can show me other pages mentioning CJ, I would sure like to see them.

3. The service manual mentions HO multiple times. In fact, it is pretty interesting to review the differences(very few and very slight) between the HO and non HO motor. It is interesting the piston clearance is greater in the HO.

Now, are the manual and specification booklets perfect sources of information. NO. Try to find a reference to the 351 BOSS in the 1971 Ford Service Manuals.

In the end the use of the term CJ was just a marketing ploy. tHO was probably used, but then someone realized it was "false advertising", so they went to the tried and true CJ from the 428 and 429 glory days.

1. were there cobra jets in 73. Well, not technically a cobra jet. A CJ.

2 what qualifies a 351 as a CJ See Attachments

3 how do we identify a CJ apart from pulling the sump off to see the 4 bolt mains , is this right? WRONG

4 mine is a 73 Q code i have the marti report it says Q 351 4V Engine

should it say CJ if it is a CJ ? CJ MIGHT BE ON THE AIR CLEANER DECAL and on the EMISSION STICKER ON THE VALVE COVER.

and just to make it more confusing im the 3rd owner a doctor bought it in 73

1 has no power steering as not stated on report. Doesn't matter

2 has air cond Doesn't matter.

3 had dealer fitted ram air as i know factory ram air wasnt available for Q code

No Big Deal.

4 diff is 9 conventional 3.25 non posi track...not an issue

hurst shifter with dealer T bar Knob. Not an issue.

it just seems a weird combo no power steering but all the go fast bits but no posi trak?

Doesn't matter.

so if any of this makes sence im just wondering if she,s a cobra jet or not

thanks guys

Dave Tommy

If your VIN is a Q code as shown on page 1 of the first attachment, and the motor is original to the car(Don't know how you determine that), then it would be a CJ. I don't think the term COBRA JET was used. CJ was used to imply Cobra Jet...thereby the lack of cobra's anywhere on the car.
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James I respectfully disagree with a couple of points here.

"Second, regarding 4 bolt mains. I have torn apart 3 351C motors- 1971,1972, 1973. All were factory 4V motors. Zero had 4 bolt mains. As stated previously, I am unaware of any 4 bolt 351C motor except the Boss and a few stragglers in 1971. It is fairly easy and not uncommon to have builders add the bolts. But a 4 bolt main is no guarantee of a 351C CJ "

Other than the Boss 351 - ALL 351's were 2 bolt mains I have never found a D0XX block with 4 bolt mains

ALL 72 351CJ's were suppose to be 4 bolt mains ***

ALL 73 351 4V 's were suppose to be 4 bolt mains ***

The *** is - when ford ran out of a part they used what was there to keep the line moving- 2 bolt and 4 blocks did get used in other cars.

That is why some people have found 4 bolt mains in 351 2V cars engines.

I have taken apart

8-10 - 71 4V motors all had 2 bolt mains

10-15 - 72 - 3 4V motors EVERY one had 4 bolt mains.

Also someone said all 73 351 4V's had smaller valves

I have heard they were used in very late 73's but I have never found any yet.

I'm only going by what I have opened up and seen.

Don

 
Wow...there is a lot of bad information in this thread. After my rant below are answers to your original questions...

As I recall, you wanted to be able to tell if a block was a CJ or not.

First, there is NO WAY to confirm the block is a CJ. You can discuss date codes on the block, and certainly 72 casting were put in 73 Mustangs....how else would a 73 Mustang bought in October of 73 have a engine. However, it is not outside of the realm of possibilities a 71 casting made it into a 73. And certainly, 73 castings were found in Mustangs. I had one. From the dealer. June 1973.

Second, regarding 4 bolt mains. I have torn apart 3 351C motors- 1971,1972, 1973. All were factory 4V motors. Zero had 4 bolt mains. As stated previously, I am unaware of any 4 bolt 351C motor except the Boss and a few stragglers in 1971. It is fairly easy and not uncommon to have builders add the bolts. But a 4 bolt main is no guarantee of a 351C CJ.

Third, in the 1973 Ford Service Manual and Specifications Manual(Both attached), you will find the following:

1. The SPECIFICATION MANUAL(Second and final printing) does not mention the HO. Only the CJ.

2. The Service Manual mentions the CJ once. In regards to the VIN. This is where the famous Q CODE designation is found. If someone can show me other pages mentioning CJ, I would sure like to see them.

3. The service manual mentions HO multiple times. In fact, it is pretty interesting to review the differences(very few and very slight) between the HO and non HO motor. It is interesting the piston clearance is greater in the HO.

Now, are the manual and specification booklets perfect sources of information. NO. Try to find a reference to the 351 BOSS in the 1971 Ford Service Manuals.

In the end the use of the term CJ was just a marketing ploy. tHO was probably used, but then someone realized it was "false advertising", so they went to the tried and true CJ from the 428 and 429 glory days.

1. were there cobra jets in 73. Well, not technically a cobra jet. A CJ.

2 what qualifies a 351 as a CJ See Attachments

3 how do we identify a CJ apart from pulling the sump off to see the 4 bolt mains , is this right? WRONG

4 mine is a 73 Q code i have the marti report it says Q 351 4V Engine

should it say CJ if it is a CJ ? CJ MIGHT BE ON THE AIR CLEANER DECAL and on the EMISSION STICKER ON THE VALVE COVER.

and just to make it more confusing im the 3rd owner a doctor bought it in 73

1 has no power steering as not stated on report. Doesn't matter

2 has air cond Doesn't matter.

3 had dealer fitted ram air as i know factory ram air wasnt available for Q code

No Big Deal.

4 diff is 9 conventional 3.25 non posi track...not an issue

hurst shifter with dealer T bar Knob. Not an issue.

it just seems a weird combo no power steering but all the go fast bits but no posi trak?

Doesn't matter.

so if any of this makes sence im just wondering if she,s a cobra jet or not

thanks guys

Dave Tommy

If your VIN is a Q code as shown on page 1 of the first attachment, and the motor is original to the car(Don't know how you determine that), then it would be a CJ. I don't think the term COBRA JET was used. CJ was used to imply Cobra Jet...thereby the lack of cobra's anywhere on the car.
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Well. For starters. VIN is stamped in block(VERIFIED!


72 Qcode 351CJ SPRINT VERIFIED by Marti


4 bolt main VERIFIED!


We need to discuss this futher!

 
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GREAT thread!

I believe Wolverine makes some very good points as it relates to marketing.

That having been said, I submit the following:

As it relates to 351C 4V blocks built during the 1971 - 1973 period, they SHOULD have ALL had 4-bolt mains with the exception of the 1971 4V (Non CJ and Non Boss blocks). SOURCE: "Ford Off Highway Parts Manual", Page 5.

It should be noted that these early 4V Blocks did have the smallest combustion chambers for their closed chambered heads...even smaller than the Boss 351!

For 1972 and 1973, the "Cobra Jet" designation is usually utilized interchangeably for the 351 4V motors produced during that period. It is true that there is often waffling as it relates to the 1973 being called "CJ" by many scribes instead of Cobra Jet. Might be truth in the "marketing angle."

The early 1971 351C 4V heads (on blocks with 2 bolt mains) should probably have the casting "D0AE-H" or "D0AE-R." The 71- 73 4 bolt main blocks should probably have heads with the "D1ZE-DA" or "D1ZE-GA" casting number.

Again, GREAT thread...please continue the conversation. For you "M-coded" owners, I am curious as to whether or not you have checked your block to see if it has 2 or 4 bolted mains:).

BT

 
Well. For starters. VIN is stamped in block(VERIFIED!


72 Qcode 351CJ SPRINT VERIFIED by Marti


4 bolt main VERIFIED!


We need to discuss this futher!
Click to expand...
 


VIN is stamped in the block??? Really. Do you have a photo of the VIN on your dash, and a photo of the VIN on the block?

 


There is a CASTING number on the block. Does not match the VIN.







 


I have taken apart


8-10 - 71 4V motors all had 2 bolt mains


10-15 - 72 - 3 4V motors EVERY one had 4 bolt mains.


Also someone said all 73 351 4V's had smaller valves


I have heard they were used in very late 73's but I have never found any yet.


I'm only going by what I have opened up and seen.


Don
Click to expand...
 


I don't think anything I have said refutes Don, or vice versa...although 10-15 72 4 bolts is quite a lot. And I don't think there is any disagreement a 351 Boss was a 4 bolt or that was a 1971 date code.

 


But, you think I would have found one a 351 4V with a 1972 date code and 4 bolt mains. I must have looked for 18 months for a good STD bore 351 4V date coded 1972 or 1973. Gave up and bought a 1971 4V with 2 bolt mains.

 


Regarding valves, "the book" lists a 351C regardless of 2v or 4v, as having 2.032-2.050 Intake, 1.705-1.715 Exhaust. Interesting on the valve springs, the HO(there is no CJ listed on the specification page of the service manual) has 299-331, the 4v 271-299, and the 2v 199-221(see page 21-22-27 of prior attachment).

 
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VIN's were stamped into both the block and trans starting in the late 60's I believe. Here is a pic of both my block and trans stamping. These both match my dash and Marti reports. That is how you know if you have a "matching numbers" car. My car is a 73 Q code and DOES have 4 bolt mains.

Jeff

108h2qa.jpg


15rnpyd.jpg


 
Same here...Got to take some picks..Mine is a late 73 4v cleveland just like Jeffs...Matter of fact our cars where built the same week,...4 bolt mains on my motor..I got it all apart right now..matching orignal block and numbers.

"Also someone said all 73 351 4V's had smaller valves

Don"

I heard on a few cleveland sites about these smaller valve late 4v clevelands..I have not seen them my self and wonder if that some kinda myth....My heads off my car and i got 2.19's on mine..And mine is a late made 4v cleveland.

 
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James, seeing you posted this - I now think you are playing -

"VIN is stamped in the block??? Really. Do you have a photo of the VIN on your dash, and a photo of the VIN on the block?"

If so ... :goodone:

If not - wellllllll :huh: No you got to be playing ... nice :goodone:

I stand by ALL 72 and 73 Q code motors had 4 bolt mains

As for your theory of Ford using up the Boss blocks in non Boss 71 cars - Sorry I have never bought that use up parts idea - they needed extra parts for service, counter sales and warrantee work

Don

ALSO 10 - 15 Q codes motors is not a lot

I have had 85 - 71-3 Mustangs

 
James, seeing you posted this - I now think you are playing -

"VIN is stamped in the block??? Really. Do you have a photo of the VIN on your dash, and a photo of the VIN on the block?"

If so ... :goodone:

If not - wellllllll :huh: No you got to be playing ... nice :goodone:

I stand by ALL 72 and 73 Q code motors had 4 bolt mains

As for your theory of Ford using up the Boss blocks in non Boss 71 cars - Sorry I have never bought that use up parts idea - they needed extra parts for service, counter sales and warrantee work

Don

ALSO 10 - 15 Q codes motors is not a lot

I have had 85 - 71-3 Mustangs
Click to expand...
James, You are a card! Good one! :goodone:

 
Since Wolverine needs documentation...I found this on ebay last week and thought it was kind of cool. Was told that it was used by salesman so they knew all available options and pricing for the 72 Mustangs. Nice in that it describes what specifically comes with each option. Has 7 pages of option detail.

What caught my eye was the 4V engine detail...check out what it says relative to our recent discussions.

Jeff

dxivex.jpg


153u3uo.jpg


 
I know I am going to get a lot of crap for this(ok more than the normal amount of crap), but my VIN number is 11 digits long. So, actually, to be fully accurate, there is a PARTIAL VIN stamped on the motor and trans.

I am guessing 1st 2 digits of stamp are first 2 digits of VIN. Last 6 digits of stamp are last 6 digits of VIN.

If the entire VIN were stamped on the motor, you would know from the VIN whether the motor was a Q, R, H, etc. I know it is hard to get good photos of stamps, but I don't see a Q in there anywhere.

And, as far as the term numbers matching goes, I have never liked that term. It is too ambiguous. If I file off the partial vin on my motor, and put on a new VIN, I can have a numbers matching car. I believe "numbers matching" has gained LEGAL STATUS as buyers are now suing sellers for misusing the term.

I may have had a lot of misconceptions going into this thread, but I am leaving with very few.

So, to be clear, I think we agree with this guy:

http://www.ebay.com/gds/Ford-351-Cleveland-Engines-Key-Facts-amp-Information/10000000001410755/g.html

However, I think he could do a better job by using columns to be consistent in the facts he is stating from one engine year to another. I think he should also cite references such as service manuals, dealer order books, etc. So guys like me can save a lot of time scrounging through manuals.

 
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