Hello to all 'vette lovers
Newbie here...
89 with stock automatic
I've got a knotty problem here.

Vehicle previous history
Cylinder heads replaced with Edelbrock performer serial # D-215-46
I've been told this is some kind of emissions designation
Also has performance cam and rockers.

Had coolant leak at rear of manifold and I replaced gasket
After 2 weeks #8 cylinder began to leak oil out of head gasket area facing
block

#8 cylinder bore - -------------O
cyl head mating surface _________________
block mating surface leak x
(The leak is directly below #8 cylinder bore )
can't get diagram to line up...

What I need is to determine if the heads had been surfaced too much
causing some kind of mis-match
I have tried to get physical dimensions from edelbrock tech dept but
N/A.
I guess the oe or production distance from cylinder head mating surface to some standard machined reference point like a point on the valve cover mating surface would tell me what I need to know.
A fel pro gauge fpp 2525 has been brought to my attention but I have not been able to get much info on this

Any and all information would be greatly appreciated


Thanks,
Reystoke

 

D-215-46 appears to be a CARB Executive Order number. Here is a
link to the relevent document.

This EO appears to blanket several part numbers across a number
of different engines from GM & FORD. For small block Chevs, it
covers Edelbrock Performer heads with the following p/n#s

6065, 6075
6084, 6085
6086, 6087
6090

Edelbrock actually designates their heads with five numerals. If
you assume the numbers above have a suffix of '9' then you get

60659, 60759
60849, 60859
60869, 60879
60909

If you use these 5-digit numbers and check the Edelbrock Performer head site,
you get:
Since you have an '89, my vote is that the heads on the car are the #60879
If a visual inspection confirms that you have:
- Edelbrock heads with
- centerbolt valve covers,
- angle plugs and these are
- mated to the OEM TPI,

Then my money says your's are the #60879 heads.

While I don't think that these #60879 heads will normally be stocked at your
neighborhood speed shop, my guess is that the dimensions in the area of interest
to you will be the same or close to the dimensions of the Performer Centerbolt
#60859 which also has 60cc chambers. I feel you could find a set
of the #60859 heads to measure within a reasonable driving distance.

Alternatively, you could also contact vendors or rework shops to
ask whether they would be so kind as to take measurements for you.

However, I feel that if you have #60879 heads, there is little likelihood
that they have been milled. The OEM chambers were 58cc - would someone go to
the expense (and risk) of cutting for 2cc +/-?

.

 

Is there any chance that you only have a valve cover leak?

There are no oil passage ways between the head and the block on a
SBC. Oil goes to the top end through the push rods and returns
through passageways in the head that empty into the lifter valley.

Other than leaks from other locations, I do not know how oil would
appear at the location you describe.

How much quantity of oil is there? What happened after you washed
the area (being careful not to get water in the harnesses, connectors
or other electrical parts) and monitored to determine the source
location of the leak? Does the oil only appear under certain conditions?

.