Block #3857656 Need input!

bobs409

 
Administrator
This darn number has been a problem in the past. I hear one thing, then I hear another as to what year it was used in, car or truck or both. :bang

I need to hear from anyone that can confirm the year(s) used and whether it's for car or truck or both.

Currently, I only have it listed for 64 truck but perhaps that's wrong. I believe I changed it in the past when someone told me it was only used in '64. ???

I'd like to only list accurate info on the site but this number is driving me crazy... :cuss
 

Fathead Racing

Well Known Member
Supporting Member 7
Truck block.

I run that # block now in my 60 Impala. In my case this is a truck block if you can belive that this is what it was intended for, or at least it has the notch in the cylinder bore. The block did come out of a single axle truck/tractor chassis. The story is that the truck driver would rave about the engines ability to pull long hills in top gear. Funny thing is when I disassembled the engine it had a solid lifter cam!
 
Bob, to my knowledge, it is primarly for the 1965 model year. If it was in a 64, that would appear to be the exception, not the rule. But, as has been mentioned MANY MANY times, by MANY MANY knowlegable members, it is by NO MEANS specifically a car block ( I know this for FACT, because I have three(3) "656" 409 truck blocks right here ! ).
As always, the same casting number is used for truck or car application, so this "number" can in no way identify if it is car or truck.

Given the number of these things out there, it would seem reasonable to suspect that it was also late 64 model year casting.
Also, I've noticed that any "new", "over the counter" blocks, short blocks, completes that have no stamp numbers on the front, seem to ALWAYS be the "656" casting number.

Certainly nothing rare about them ( in terms of W block stuff anyhow;) )
 

bobs409

 
Administrator
Ok, so if I read correctly, this casting number was used in both 1964 & 1965 and for both car and truck applications.

Agreed? :D
 

60biscayne409

Well Known Member
Ad the same problem , i always think that my 1965 409 656 num was a truck block that was what people always toll me , but this year i had to change the head gasket , and you know what no notch on the trop of the cyld , so , its very hard to tell , i think to make sure you have a truck or a car block you have to take the head out,to be sure .
But truck or car block 656 are good block , and thats it .
60biscayne409
 

rstreet

Well Known Member
Supporting Member 17
Ok, so if I read correctly, this casting number was used in both 1964 & 1965 and for both car and truck applications.

Agreed? :D

Yes I'm for that vote This number is on a 65 400hp and a 65 truck here
Robert
 

SSpev

Well Known Member
Supporting Member 3
My hollander interchange only list 656 as a truck block, late 64-65. But I am sure I have seen 65 j code car block with this casting. 64 car blocks????? I have a 656 truck block with a julian date of 313.
 

petepedlar

Well Known Member
Supporting Member 3
656 Block

I just sold a 1965.... 656 car engine code JA (400HP). I have a 656 truck replacement engine purchased over the counter in 1970.....with no suffix code stamped, but dated 1965

Dave
 

Phil Reed

Well Seasoned Member
Supporting Member 10
65 only

Ok, so if I read correctly, this casting number was used in both 1964 & 1965 and for both car and truck applications.

Agreed? :D

I feel it is 65 only. 64 used the 3844422 blocks. Why there are 2 versions of the 656 block is something I don't know.

Now, when you mention late 64, keep in mind that 65 production started in Aug. 1964. I know at production changes, we may see a period of overlap. If a 64 Impala was being built in late July and there wasn't any 422s ready, you can be sure that the assembly line put in whatever was available and probably the 656 was put it. The classic example of this was on the new 1962 Super Sports. The trunk panels were not ready so about about 6 weeks, I think, all SS's got the Impala trunk panel.

IMO...the 656 was 1965 production only.
 

chevymusclecars

Well Known Member
Supporting Member 5
I have a 1970 Chevrolet parts book that calls out the 656 block for 1965 passenger cars. We know that they were also used in trucks but that is a seperate parts book that I dont have.
 

jim_ss409

Well Known Member
Supporting Member 5
Colvins' By The Numbers books never seem to cover truck stuff. I've got a 656 block that has the truck notches. It seems like 656 truck blocks out number 656 car blocks. I always thought they were for the 65 model year only. And of course, since that was the last year for the 409 most unstamped replacement blocks seem to be 656's.
 

bobs409

 
Administrator
Well, I think we narrowed it down to 1965 car or truck & replacement block for sure. I could add a note that this may have been used very late '64 as well. :dunno

Judging by the replies, I can see why I was confused. :D
 

SoLo64

Member
i had a thread about this also and someone help me out alot if you go read the thread 409 car or truck motor help it explains how to tell the difference by looking at the block assembled or with the valve covers off and of course apart hope this helps
 

Bungy

Well Known Member
Supporting Member 3
Thought I'd through my 2 cents worth in on it (if it's even worth that). I am by no means an expert, just going off of my experience. I have three 656 blocks and all are machined for truck use. I have also seen these blocks without the notches and stamped with passenger suffixes. It's always been my understanding that whatever the casting number was, it was used for both truck and passenger cars. The only difference being the machining process. (drilled and tapped front for horseshoe mount and machined notches to lower compression) ie 422 blocks for both truck and passenger car. (was the 409 offered in trucks from day one?)
Anyway, I agree with listing it as 65 car and truck with a notation for early 64.

:cheers
 

Ronnie Russell

Well Known Member
Supporting Member 2
All 409 motors are truck motors. Ask any Ford guy at any " cruise night" and he will tell you. After all, that is what many magazine articles call them, so it must be true!!!!! :roll :roll :roll
 

Phil Reed

Well Seasoned Member
Supporting Member 10
not quite

All 409 motors are truck motors. Ask any Ford guy at any " cruise night" and he will tell you. After all, that is what many magazine articles call them, so it must be true!!!!! :roll :roll :roll



That's not quit right Ronnie. They build them to race and they wouldn't run so they put them in dump trucks!!:doh :doh
 
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