340 engine, 340 cast in block, 318 stamped below cyl head???

[volvo 4 life]

i just acquired a 1969 340 engine. It strikes me as kind of an oddball and I would like verification that it is in fact a 340 and not a 340 block that was bored to 318 specs by the factory. The casting on the driver's side of the block clearly reads 2780930-340-5 which to me denotes a 340 casting. The pad under the front of the driver's side cylinder head however is stamped EW318... so what do I have here? The engine also has j heads on it which I thought came along in 1970 but I suppose they could've been swapped on, it has been apart before. The casting date appears to read 8-11-69. Thank you for any info!!!

 

[volvo 4 life]

Here are some pictures

 

[A383Wing]

the crank stroke is the same, and the bore on a 340 is larger than a 318...so you can't "bore a 340 block" to make it a 318. Find the bore specs for both engines and measure the bore in your engine to find out what you actually have

 

[POMONAMISSEL]

whats the bore measure ?

 

[POMONAMISSEL]

date codes are from the casting time , and this stuff would not have seen a 69 car . would have been used in a early 70 car . but again whats its bore size , 318 @ 3.9 340 @ 4.04 .

 

[volvo 4 life]

I haven't measured the bore on it yet, really wasn't looking to pull the heads but I definitely don't want to build this engine thinking it's a 340 when in fact it's a factory screw up and they bored it to 318 specs. Does the casting on a raw 340 actually have larger bores than a 318 before machining?

 

[POMONAMISSEL]

not sure , would you think the factory down sized a 340 to a 318 . man it would have really thick bore sleeves . only one way to know for sure . pop a head .

 

[POMONAMISSEL]

you know that 318 stamping looks like there is another with in it like a 4 and 1 and 8 over 0 . maybe some one was after cheaper insurance rate , or and this is the real story , someone running a cheater motor in race class . some stampings were very lightly done . can you get a better view of it .

 

[volvo 4 life]

I'll try to get a better picture of it tomorrow. My honest thought was that somebody in charge of stamping these things at the factory might have screws up, thinking this engine was a 318 when in fact it's actually a 340. I think that's more likely than an underbored 340 block. I'll be pulling a head tomorrow anyway but it's still pretty confusing that it would have 2 different markings on it!

 

[volvo 4 life]

Now that I look at it closer I see what you're talking about! It looks like there's almost a very faint 3 4 0 under the heavy 318 stamping. I agree the 318 stamp is unusually heavy compared to the rest of the Lettering and other engines I've seen.

 

[Hosehead]

That's a restamp. The 318 doesn't match the rest of the numbers at all! Weird!

 

[4mayhemi]

Now that I look at it closer I see what you're talking about! It looks like there's almost a very faint 3 4 0 under the heavy 318 stamping. I agree the 318 stamp is unusually heavy compared to the rest of the Lettering and other engines I've seen.

The restamped 3, 1, and 8 is the wrong font. Poser in a backward way. Street racing?
P=Premium fuel
2868 = June 4, 1969 (assembled before the casting date, quantum leap style)

Cast 8/69 is for 1970. I bet it should be "FW340" for an early 70 build.

 

[wilmacmike]

The restamped 3, 1, and 8 is the wrong font. Poser in a backward way. Street racing?
P=Premium fuel
2868 = June 4, 1969 (assembled before the casting date, quantum leap style)

Cast 8/69 is for 1970. I bet it should be "FW340" for an early 70 build.

Looks like the 8 is upside down also. Crazy

 

[volvo 4 life]

I guess I did end up with an oddball either way haha. I'm going to pull the heads today and I'll report my findings, hoping for good bores and Pistons so I can re ring it and go!