Engine Identifacation, Worth Perf rebuild?

[ozmopar1966]

The block casting number is 3698830.440.10
on the id pad is
J440
3 9 E2

I have worked out it is a 440, but the rest?

Is this block worthwhile for a rebuild with performance in mind?

Thnaks

Eddy

[rumblefish360]

Sure, why not? What is your concern?

[Duster_340]

You have a 1973-1978 440 casting block. The main issue is to sonic test the block so you know how thick the cylinder walls are.
Thicker walls make more power.

[MoparMarcIdaho]

and how much do you want to get out of it as far as performance?

[John Kunkel]

J440
3 9 E2

J= Year code for 1973

440= Displacement

3 9= Assembled on March 9, 1973

E=Cast crankshaft

2= Assembled on the 2nd shift

[ozmopar1966]

thnaks much appreciated

Eddy

[ozmopar1966]

what does the 10 part mean after 440 in the block casting number?

Eddy

[MoparMarcIdaho]

possibly mean a 10 under main bearing on the crank,John?

[John Kunkel]

The dash number following the casting number on the side of the block is called the Casting Core Index Number, it identifies the number of core plugs that were replaced in the casting core that is used to make the sand mold for the block.

A high number supposedly increases the chance of core shift but I've never seen any definitive proof.

[ozmopar1966]

thats similar to what i heard, were 1 is the best and 10 the worst, now its got me worried?

Eddy

[72Challenger]

It's actually nothing to worry about. The people replacing the cores may have been more carefull than the ones who put the originals in. Or maybe not. The only way to tell is to get the block sonic tested. This should be done on any block intended for very high output anyway. And if you're just doing a stock or mild rebuild, it doesn't really matter. What level of performance are you shooting for anyway?

[ozmopar1966]

looking at 450hp at the rear wheels in a 3000lb australian wagon

Thnaks

Eddy

[ozmopar1966]

More info I found, can anyone validate this?

CORES THICKNESS
core casting////cores used/////maxrebore//////cyl/casting
cid-1 & 2 -------------------.060-----------perfect
cid-3 ----------1 row-------.040-.055------sonic test
cid-4 ----------2 rows-------.040----------2cly offset
cid-5 to 8 ------3rows---------------------must sonic test
cid-9 & 10 ------all-----------.010---------poor


the core number is on the left side of your block.

like ( 3698830.440.10 ) the 10 is your core.

if you can get a core 1 or 2 you can all out race even blown.



Eddy

[John Kunkel]

Once again, a low dash number is no guarantee of a borable block, only sonic testing can determine a block's suitability for overbore.

You have to realize that these blocks were mass produced in a foundry where, at any given time, the workers might have been hung over, drunk, tired, bored or all of the above. This makes the quality of any individual casting unpredictable even with the best of tooling