Login  /  Register  
  Home  -  Forum  -  Classifieds  -  Photos  -  Links     

  << Previous Topic | Next Topic >>Return to Index  

C6OZ-6250-B Camshaft Design Change?

December 6 2012 at 7:58 AM
  (Login sah62)
Members

Yesterday I had a telephone conversation with someone who claims that the cam info (including the Cam Doctor results) posted on my 428 CJ cam ID page http://www.428cobrajet.org/id-cam) describes a different version of the C6OZ-B cam than what was installed in the cars during factory assembly. That is, there's a difference between the factory-installed part and the part later sold as a service replacement. He supported his argument by claiming that a cam grinder he's worked with developed a pattern by copying an original cam removed from an engine in the early 1970s. They discovered that this cam used a different LSA than the part sold "over the counter".

So I listened and offered to go back into my research. Interestingly enough, I did find two different engineering numbers that cross to the C6OZ-B service part number. This suggests that there was at least one design change made during the part's lifetime.

Does this sound plausible? If so, does anyone know anything about the design change?

Scott Hollenbeck
Administrator, Mustang 428 Cobra Jet Registry
Owner, Muscle Car Research LLC

 
 Respond to this message   
AuthorReply

(Login x4rdtech)
Members

Re: C6OZ-6250-B Camshaft Design Change?

December 6 2012, 8:14 AM 

Makes me wonder if the C4AZ-B I had H&M grind for me when I first got my car back was the same or their updated profile.

[linked image]

 
 Respond to this message   

(Login bwrinkle)
Members

C4AZ-B cam

December 6 2012, 9:03 AM 

Hi Bobby,

The specs of the original Ford C4AZ-B seem to be different from the H/M cam. I am going from memory but will look in my original information tonight. The Ford cam was .500 lift and 324 advertised duration and the H/M specs are 290 advertised duration and .526 lift. Again, I msafrom memory here and I am an old timer so I will look tonight and post more tomorrow.

Byron

 
 Respond to this message   
Bobby Spears
(Login x4rdtech)
Members

Re: C4AZ-B cam

December 6 2012, 11:09 AM 

I was just curious and I don't have it now.I gave it to Earl E in Lake Havasu,AZ for helping me with my new hood paint job.I think he has it n=in his 56.I have the newer Crane Z300-8 according to the two different cam cards I have for it.The one I have now is retarded 4* kind of what I done when I had one the first time I had my car.It had too much torque for the 7" cheater slicks until I was in 2nd then wow.Now of course I have it as per the later cam card specks.

[linked image]

 
 Respond to this message   
Ben
(Login BH107)
Members

Old specs

December 6 2012, 11:29 AM 

Maybe someone can back me up on this, but I thought I read somewhere on here that the way the duration is measured now was different than back then? Maybe that is the difference in those measurements? And I'm pretty sure the .526" of lift is to account for lash and still give .500" of true lift.


 
 Respond to this message   

(Login Henrysnephew)
Members

I'm betting Dennis K will be your man! N/M

December 6 2012, 8:45 AM 


 
 Respond to this message   

(Login ddbigengin)
Members

Maybe y'all can help me with this

December 6 2012, 9:37 AM 

I keep trying to find the specs for the C6Az-Z cam.(not -A)
I'm also trying to find out if it COULD have been put in a 390 2bbl. High perf 390 2 bbl. (vin code x) in a 68 torino gt. or were all of them C7AZ-A cams?

 
 Respond to this message   


(Login 10w30dna)
Members

C6OZ-B is hydraulic C4AZ-B is mechanical

December 6 2012, 1:16 PM 

Ask him what numbers he found and what you are using to ID the cams. ........... the casting marks or stamped numbers? I'm very skeptical. My main question is what numbers do you have for the two versions of C6OZ-B ?Those two cams C6OZ-B/C4AZ-B are not even close to each other and could not be confused as same..

Engines are like garages,never big enough! Check out my distributor restoration sites! Nehttp://428cobrajetcars.com


    
This message has been edited by 10w30dna on Dec 6, 2012 1:40 PM
This message has been edited by 10w30dna on Dec 6, 2012 1:38 PM


 
 Respond to this message   

(Login BH107)
Members

Two different discussions.... n/m

December 6 2012, 1:35 PM 


 
 Respond to this message   

(Login ddbigengin)
Members

My bad/sorry

December 6 2012, 2:59 PM 


 
 Respond to this message   
Scott Hollenbeck
(Login sah62)
Members

Re: C6OZ-B is hydraulic C4AZ-B is mechanical

December 6 2012, 1:48 PM 

Right, there's some thread hijacking going on here... wink.gif

The two engineering numbers I found are C7OE-6250-A (crosses to service part C6OZ-6250-B) and C7OE-6250-B (crosses to service part C6OZ-6250-B1).

Scott Hollenbeck
Administrator, Mustang 428 Cobra Jet Registry
Owner, Muscle Car Research LLC

 
 Respond to this message   


(Login 10w30dna)
Members

Odd part#/ Master Cross reference book?

December 6 2012, 3:21 PM 

The only way I find C6OZ-6250-B1 is the the cross book. I never saw an actual tube/cam container with that extra "1" behind suffix B........ what are actual cam markings in question?

Engines are like garages,never big enough! Check out my distributor restoration sites! New http://428cobrajetcars.com

 
 Respond to this message   

(Login sah62)
Members

Re: Odd part#/ Master Cross reference book?

December 6 2012, 3:56 PM 

That's where I found the number, too. The only markings I'm aware of are described on my ID page. The real question is what's different about the cams that required two different engineering numbers.

Scott Hollenbeck
Administrator, Mustang 428 Cobra Jet Registry
Owner, Muscle Car Research LLC

 
 Respond to this message   

(Login tbolt2)
Members

Re B and B1 suffixes ...

December 8 2012, 10:11 PM 

The 306 deg C3AE-D/H/M = C3AZ-D/D1/D2 service cams uses similar suffixes, the differences lie in heat treat flame or induction hardening and phosphate coat. The grind specs are the same. I'd expect a similar scenario with the B and B1 suffix.

Regards,
Dennis

 
 Respond to this message   


(Login werbyford)
Members

3 or more cams in this thread- some numbers

December 6 2012, 7:55 PM 

Lots of cross-threading, thats ok I guess.

For the 390gt/428cj cam (also later in the 351cj, retarded)
270-290-117 adv dur
172-184-116 at .100
207-220-116 or so at .050 as noted already
Ive only seen this one spec and the couple Ive measured agree. Wish Id measured some new ones back when they were $20 each from Ford.
The Lunati cheater cam has a LOT more duration, more than even the "C" cam but it keeps the stock .481 .490 lift. No way the Lunati specs are stock CJ, it would have quite a rump-rump idle.

I would say though, that some of the early 428cj road test cars ran awfully good. Either they all had good weather or were loose builds, or could some of them have had the c8ax-c "C" cam at
282-296-117 adv
188-196-116 at .100 lobe
220-230-116 at .050 per Ken at Oregon
(same cam later used in the 429cj)

The 3rd cam is the one that Bobby asked about, the 427 series, even the adv duration on those was stated differently.
Theres the "4v" cam or "AA", c3az-aa, stated as either
274 or 276 or 306 adv duration (all same cam AFAIK)
228-228-114 approx at .050
Comp 270s sounds EXACTLY like it, I just noted that staring at mine, brought back memories of our 427/410car.

Theres the "8v" cam, or "K", c3az-k etc, stated as either
288 or 290 or 324 duration (again all same afaik)
244-244-114 approx at .050

The c4ae-b or "B" cam is the same except on tighter 106 centers so its quite a bit rougher and a bit stronger.
Also listed as 324 duration, could also be called 288 or 290 tho Ive never seen it called that way.

The 4th cam question was about the 390-2v Premium cam.
Its listed as
256-266-112.5 duration adv
156-166-112 at .100 fixing a suspected typo in the Ford book
192-199-112 at .050 per PAW, they used to sell it
Good vanilla replacement for the almost liftless pre-66 390/300 cam.

Sure was confusing before the .050 standard.
Hope this helps, I am always trying to refine this info for the Gonkulator

 
 Respond to this message   
S. Douglas
(Login ddbigengin)
Members

Thank You Werby!

December 6 2012, 9:04 PM 

I never got a definitive answer before.Must of been that 10.5 comp. that made it run so nice.


sd


    
This message has been edited by ddbigengin on Dec 6, 2012 9:06 PM


 
 Respond to this message   

(Login tbolt2)
Members

Re: C6OZ-6250-B Camshaft Design Change - here are some different grinds ...

December 8 2012, 10:28 PM 

1966 390-GT
C6OE-A = C6OZ-A
270 270
18-72 68-22
.278 lobe lift
40 overlap
115 LS

1966 390 275/315 2V/4V Fairlane
? = ?
256 256
16-60 55-21
.253 lobe lift
37 overlap

C6AE-A = C6AZ-A
256 256
18-58 17-59
.253 lobe lift
35 overlap
110.5 LS

390 GT
C7OE-B = C6OZ-B1
270 290
18-72 82-28
.278/.283 lobe lift
46 overlap

What is the grind specs of this other CJ cam? Is the intake 20-70?

Don't forget, what's used in service (Z) doesn't necessarily reflect what was originally used in production (E).

Regards,
Dennis


    
This message has been edited by tbolt2 on Dec 8, 2012 11:04 PM
This message has been edited by tbolt2 on Dec 8, 2012 10:33 PM


 
 Respond to this message   

(Login sah62)
Members

Re: C6OZ-6250-B Camshaft Design Change - here are some different grinds ...

December 9 2012, 3:29 AM 

I don't have grind specs, Dennis. Ultimately that's what I'm trying to determine. The fellow told me that the LSA differs from the service version of the cam. Do you have anything on the C7OE-A/C6OZ-B cam?

Scott Hollenbeck
Administrator, Mustang 428 Cobra Jet Registry
Owner, Muscle Car Research LLC

 
 Respond to this message   

(Login tbolt2)
Members

Re: C6OZ-6250-B Camshaft Design Change - here are some different grinds ...

December 9 2012, 11:14 AM 

I don't have grind specs, Dennis. Ultimately that's what I'm trying to determine. The fellow told me that the LSA differs from the service version of the cam. Do you have anything on the C7OE-A/C6OZ-B cam?

----

Not really, just C7OE-B.
Nothing on C7OE-A.
The Muscle parts book lists the C6OZ-B, however the timing events match what I have on the C7OE-B cam.

There may be a 390 GT cam that is 20-70 intake, instead of 18-72. That would give a different lobe separation angle.

Any Cam Doctor info or id marks and paint stripes on known production and service part 390-GT/428 CJ cams?

Regards,
Dennis



 
 Respond to this message   
Current Topic - C6OZ-6250-B Camshaft Design Change?
  << Previous Topic | Next Topic >>Return to Index