Shadoa

Hi
We got this engine and we tried to identify it.
But the casting number is in bad shape.
When I check the heads it says : 3970126
Behind the block it says : GM41 3970010
I know it's a motor between 67 and 70.

sofakingdom

iTrader: (1)

Can't tell, from the #s you posted.

The heads are 2-bbl heads used on both 327s and 350s in the early 70s. Those at least, belong in the trash.

The block is a 4" block. Could be either.

Keep in mind, EVERY SBC head will bolt to EVERY SBC block. Which means, what heads are on that block now, are in no way constrained to be the ones that came with it, or even vaguely similar. You can for example bolt 96-2000 heads to a '55 265 block, or vice-versa. You can bolt double-hump fuelie heads to a 74 Impala block. You can bolt L98 heads to a 66 327 block. And so on.

There are so few motors that are 40 yes old that haven't been rebuilt, that whatever that motor started out life as, it's 99.99999% certain to be something else now.

You can't possibly "know" that it's 67 to 70. That block casting was used up until about 80.

Only difference between a 327 and a 350, in that block, will be the crank and pistons. Only way to know for sure is to look at the crank casting #; or measure the stroke; or measure the distance between the wrist pin and the top of the piston. But even that last can be fornicated; it's even possible to put 327 pistons on a 350 crank. You'd end up with hella low compression, but it would probably run. Been done before.

Tear it down and look at it. If you don't even know what it is, then you don't know what condition it's in, meaning, it's not a "motor", it's a "core". Take it apart, keep what's worth keeping, throw away the rest, move on.

Shadoa

thx for the heads spec.
Maybe you can help out for those heads at the same time :462624

Shadoa

It's a 327 from a k-10 1968 I scrubbed it enough to see the YX at the end..the X was fine but the Y looked like a T ...
The ending part is 1131YX
November 31 k-10

sofakingdom

iTrader: (1)

That stamping code only tells what engine THE BLOCK was part of when it left the factory. It DOES NOT tell you what THE ENGINE you have in your hand is NOW.

Only way to know that FOR SURE, is to look at the parts that are installed in it.

624 are some of the worst of the 70s smogger turd heads. Very large chambers, poor flow, lightweight casting prone to cracks. Into the trash they go with the 126s.

Shadoa

You mad bro? I just said I FIGURED the CASTING NUMBER.lol
Don't worry , when it's gonna be the time to use that motor I will rebuild it. Whatever what it was or what it is right now. >_> The fact :it's from a k-10. Can be usefull...since some people "sometime" give a bit more for a block closer to the year of their project.( I don't think I teach you anything there.)
And I never said I was going to use it lol , I just said I have that motor ...who knows for how long ...I don't even remember where I got it ..anyway
For now I got other stuff to do, I'll open it later ....when I'll really care to know what's inside of it..... I'm doing an overall on my 86.Painting the whole thing, inside and out.

Shadoa

Just like that what do you think of the Quadrajet carb ? better or worst then the 650?
-_- And I'll have to buy myself some heads since you're making me trash all the one I find in the garage.

sofakingdom

iTrader: (1)

Depends on the individual Q-Jet, and the individual 650; and the use they're being put to.

Both are good carbs when properly used. Both can be worn out, destroyed, have their screw threads ate up by dissimilar-metal corrosion, etc.

People always post up those stamping #s that they find on THE BLOCK and expect that somehow there's useful information contained in them. The fact is, that stamping number tells you stuff about what car THE BLOCK came in; it tells you what pistons cams in THE BLOCK from the factory; it tells you what heads THE BLOCK had bolted to it; what cam THE BLOCK had in it; and so on. They post up on the Internet all about "I found a block in my buddy's uncle's boss' girlfriend's cousin's garage with stamping xxx how much HP does this block 'push'?" and the like. However, the VAST majority of BLOCKS of that age found today, have been "rebuilt". Most of the time, that is done by a company known as a "rebuilder". The way the commercial "rebuilding" process works is, they take a ginormous pile of engines; tear them all down to their individual pieces; put all the cranks in one pile, all the blocks in another, all the rods in another, all the heads in another, etc. etc. etc.; throw away all the things that wear out, like pistons, cams, gaskets, and so on, as well as any major castings that are too badly damaged or too worn out to be renewed; take all the "good" parts (ESPECIALLY the steel cranks and the better heads) out of the piles and build their own cars out of them or sell them to their racing (usually round-track) buddies; and mass-produce replacement engines as cheeeeeeply as possible from the remaining heap. Therefore in a typical "rebuilt" engine you are likely to have a BLOCK (complete with stamping code) out of one engine, a crank out of a completely other one, 2 heads from 2 completely other engines, universal "rebuilder" cheeeeeeepie low-compression pistons, 8 random rods from out of the pile, and the all-imoprtant generic copy of the 929 cam. At that point, the stamping code tells ABSOLUTELY NOTHING WHATSOEVER about what THE ENGINE now is, because all of the parts that differentiated THE ENGINE from other engines have now been changed. THE BLOCK still has whatever code stamped on it, but THE ENGINE is the same as any other that they "rebuilt".

I recall one short block a guy brought me I guess it was about 25-30 years ago for me to build, that he had spent all kinds of time trying to track down and extra money to acquire, thinking that he was getting a "superior" foundation for his hot-rod. It was a 010 block, which somebody had told him was "the best" 350 block to get because some of them were "out of a Vette", but failed to tell him that some others were out of 2-bbl Impalas, others out of Malibus, others out of trucks, etc. He was just positive that somehow this motor was going to "push" more HP than some other motor because the stamping code showed it had come from a Camaro and someone had told him those had more compression than others and a steel crank (which I could tell from the outside it wasn't but he didn't want to hear that). Seems like instead of paying the usual $50 for a core, he paid like $250, which in todays dollars would be like buying a junk motor for about $600. Lo and behold, when we tore it down, it had Badger "rebuilder" deeeeep-dished pistons in it, the crank was a 442 CASTing, it had 3 #5 and 2 #2 rods in it, and the cam was .... you guessed it .... a 929 replica. That's how much REAL value in identifying that motor, that the stamping code had. His face turned green when he realized how much he had spent barking up the wrong tree by paying attention to the stamping code, and how little value (zero) it actually provided in informing him about what he was really buying.

I have no clue of course what you plan on doing with that motor; and I'll help you make it into something GOOD as much as possible. All I'm trying to do, is to keep you - and anyone else happening to read this - from making that same kind of mistake. Lesson #1 is, the stamping code means ABSOLUTELY NOTHING WHATSOEVER unless you have had continuous personal association with that motor from the day it left the factory - unlikely at best for a 30-40 yr old motor. Lesson #2 is, VERY VERY FEW old stock heads are worth sinking even ONE DIME into: most people want their heads to turn into chicken salad but they're starting out with chicken .... something else, and that isn't going to happen, and instead they throw money down the drain. Lesson #3 is, the CORE parts, i.e. the wore-out thing you're rebuilding, is THE CHEEEEEEPEST part of the rebuild, and there's no sense in pouring money into a anything less than THE RIGHT ONE(s). Lesson #4 is, you can take the block from of a 160 HP 350 2-bbl out of a Grandma's 75 Impala and make a 600 HP screamer out of it, EXACTLY the same as you can build such a motor out of any other block, because THEY'RE ALL EQUAL once you take all the guts out.

And of course, the all-important Lesson #0 is, the PARTS are what they are; if you want to know what something is, pay no attention to the "codes" stamped by the factory on it(whether it be a block, rear end, or whatever), but instead tear it down and see what it REALLY is. It needs to be renewed anyway no matter what it is so you're not losing anything by taking it apart, you're only learning the truth.