open or closed chamber cleveland heads, need help ASAP

J

jterry831

Member

Apr 25, 2005

38

0

6

Jun 2, 2006

#1

• Jun 2, 2006

• #1

Hey guys, I have a cleveland with 4v heads that have a casting number of 9m11 on them. Are these open or closed chamber heads?

Thanks!

Jimmy

 

D

D.Hearne

New Member

Sep 29, 2000

11,730

6

0

south louisiana

Jun 2, 2006

#2

• Jun 2, 2006

• #2

That's the date code not the casting numbers. Do they have a "4" cast into one corner next to the valve cover rail ?

 

rbohm

Founding Member

Apr 12, 2002

6,698

550

204

tucson,az

Jun 3, 2006

#3

• Jun 3, 2006

• #3

the only way to know is to pull the heads and look. even in 1970 there were two versions of the 4V heads on the 351c.

 

J

jterry831

Member

Apr 25, 2005

38

0

6

Jun 3, 2006

#4

• Jun 3, 2006

• #4

Is there any other way to tell if they are open chamber or closed chamber besides pulling the head off? They have a 4 in the corner of the head next to the valve cover.

thanks for the info!

 

C

commonrail

New Member

May 13, 2006

23

0

0

Jun 3, 2006

#5

• Jun 3, 2006

• #5

Post the casting number on the site. Most non boss 351C heads are DOAE-N

 

dodgestang

Active Member

Dec 15, 2003

1,360

0

37

Cecil County, MD

Jun 3, 2006

#6

• Jun 3, 2006

• #6

jterry831 said:

Is there any other way to tell if they are open chamber or closed chamber besides pulling the head off? They have a 4 in the corner of the head next to the valve cover.

thanks for the info!

Click to expand...

No way to tell open vs closed with 100% accuracy without turning head over and looking at the chamber.

1970 date code = much higher probability for closed chamber
1972-73 = much higher probability for open chamber

 

9

96 DOHC Cobra

Founding Member

Oct 14, 2001

542

0

16

Cerritos, CA

Jun 3, 2006

#7

• Jun 3, 2006

• #7

Since you know for sure that the heads are 4V heads (the "4" in the upper corner), and the casting date is "9M11" (December 11, 1969) they have to be closed chamber. The only 4V heads used on 70-71 models were closed chamber heads.