[j4m]

I have a fresh 1977 Mk IV with 781 heads, bored 0.030 over, zero decked, domed pistons (9.6:1 CR). The block is a series coolant flow and has not been modified (additional holes drilled between cylinders on exhaust side) for parallel flow.
? Will a fel-pro 1027 gasket cause an overheating issue?
?Does parallel flow really make a cooling difference ?

Asking the questions to see if I should swap out gaskets prior to putting in the car--and-- If so, should i switch it to parallel flow.
Please comment on my gasket choices as well. If I have to pull the 1027's, planning on 8180PT2 (or 502SD) if left series and 1037 for parallel.

Fel-Pro said the 1027 would work, but then later said to drill the holes and switch to 1037 "if" it was street/strip vs daily driver.
So, would like some input from folks with experience. To see if the gaskets need to be swapped out and is the switch to parallel worthwhile.

 

[BillK]

I dont know that I would worry about it that much. I dont think the difference will actually affect the overall engine temperature if that is what you are worried about. It affects the way the coolant is distributed to different areas of the heads and block more than anything. There are probably thousands of engines running around exactly like yours is now and not having any issues.

If you were just starting the build I would say yes to drilling the holes but I dont think I would take it apart to do it now.

 

[Malibu ss 64]

1027 will work with series cold block but they have a softer pre flatened copper wire and fel pro spec them for alu heads only. So not sure how good they work with iron heads.
8180PT2 should work.
I have a 489 thats been running with series cold block for 15 years never seen over 190 deg in the head or 175 in intake.
The paralell cooling is supposed to make temp more even in the heads Ive been told.

 

[j4m]

Thanks Bill and Malibu. Next build will get drilled.

 

[bracketchev1221]

We used to drill all blocks regardless when I was at the engine shop. I have a 2 bolt on the stand now that I just drilled. If your engine is on the stand, I would flip it upside down and drill it.