Block Fill - 1/3

[Ron R.]

Found a Chevy engine block with the numbers of 3869942 p and gm1 on it. Engine has been 1/3 block filled. My books tell me its a 1966 or 1967 chevy Big block. I want to use as a motor for a NCRS 66 or 67 - 427 car. Looking on non corvette sites I've heard mixed reviews on using a engine that has been block filled as a street motor. Most suggest

[Joe L.]

Re: Block Fill - 1/3

Ron-----

I would not even consider using a block which had its cooling jacket partially filled.

[Mike M.]

Re: Block Fill - 1/3

due to the fact that the big block chevy engines tend to runhot, i wouldn't spend the $ on a 1/3 filled 427 that i intended to run on the street. not so with the small blocks which tend to run cool. have a "283" with 10K+ miles on it that we filled about 1/3 up the jackets. it ran thru the summers heat to the Marlboro convention from maryland turning 3500 RPMs most of the time with 3.70 ring and pinion. i usually run 4.56 R&P where the old sbc has frequently seen 7500 RPMs on the 1/4 mile. go with jhope's advice on the Mark IV.mike

[Ron R.]

Thanks - I'll pass on the block. *NM*

[Wayne M.]

What's the purpose of "block fill" ? *NM*

[Dick W.]

Re: What's the purpose of "block fill" ?

Wayne the water jackets are poured with different materials (early on we used Portland Cement) to stabilize the cylinders. Keeps the walls round. Good for short trips (1/4 mile). I have seen them poured level to the deck which limited your time to run.

[Wayne M.]

Thanks, Dick -- what a waste of a 942

I suppose this is why they're referred to as "boat anchors" by the small block crowd. Would never have guessed the reason without your explanation.

[Clem Z.]

Re: What's the purpose of "block fill" ?

the stuff is "expanding grout" used to anchor machinery into the factory floor. since cement shrinks when it hardeneds it does no good. i have seen "filled" block used on the street and the water temp was not a problem BUT the oil temp did go higher than normal because there is no cooling at the bottom on the cylinder case to help cool the oil. you loose a few quarts of coolant capacity but not enough to cause overheating

[Clem Z.]

PS i did this on all my 400 blocks used for

circle track racing and had no overheating problems.