Block stampings?

[Brando 91LX]

I have 2 blocks. In the lifter valley one has XXX and the other has YYY. Does this have any significance?

 

[Brando 91LX]

Anybody?

 

[woodsy]

no signifigance, more myths about higher nickel content

 

[Brando 91LX]

thanx

 

[Mustang78]

i think the XXX is flat tappet cam/lifters, and the YYY block is roller cam..this is just what i've heard, you might wanna verify that before buying parts

~Mark~

 

[Marlboro_Man]

i think the XXX is flat tappet cam/lifters, and the YYY block is roller cam..this is just what i've heard, you might wanna verify that before buying parts

~Mark~

My 87 block has "XXX" and it is a roller block.

My 89 block has "YYY" and it is a roller block.

So there goes that theory. I was wondering the same thing though, What does it mean?? Maybe different places they where assembled?

 

[txstang84]

I think the foundry guys got bored one day and figured they'd have some fun with us...keep us guessing.

There used to be a rumor that only the HO blocks had it, but that's all balderdash too...hell most 5.0's bear the casting numbers E7SE, E7TE, F1SE or something like that...none of which are specifically designated for Mustang use only. there are very few blocks that were specifically for Mustangs, and most of them were back in the 60's and 70's (Boss, CJ, SCJ,)

 

[Sims6986]

sorry for bringing this thread back up, but the late model i pulled from my 70 mustang has e85e stamped on the block and the heads, as well as the XXX in the valley. What does this mean? I don't know what year it is, and it is fuel injected, which i'm getting rid of, so what manifolds can i use also? thanks in advance.

 

[txstang84]

More than likely, the part number you saw in the block was actually E6SE...if the heads say E6SE...dump them in the junkyard...they're useless unless you're building a grocery getter. The block is fine to use unless you're building something to do 9's. No worries, all the roller blocks interchange...again, the XXX in the valley might just be some kind of identifier for the foundry.

 

[aleborjas]

wich one is the best one? stock ones....

 

[seijirou]

I hear the 'XXX' blocks tend to require more lube and are prone to be dirtier.

 

[Sims6986]

I'm planning a 347 stroker with aftermarket heads, but what intakes for a carb can i use?

 

[GSP393]

The letter designation is the decade starting in the '60's with the letter C with the year following such as C9, being '69 followed by other letters/numbers. I'm not sure about the '90's. My 351w block for my stroker has D4 cast in it, so it's a '74 model block.

 

[seijirou]

The letter designation is the decade starting in the '60's with the letter C with the year following such as C9, being '69 followed by other letters/numbers. I'm not sure about the '90's. My 351w block for my stroker has D4 cast in it, so it's a '74 model block.

It just follows the alphabet.
C = 60's
D = 70's
E = 80's
F = 90's

 

[GSP393]

It just follows the alphabet.
C = 60's
D = 70's
E = 80's
F = 90's

That's what I meant, but you described it much better. Thanks

 

[seijirou]

That's what I meant, but you described it much better. Thanks