I know a guy who is selling a 400 short block.  Its just the engine block.  Anyone know how much it is worth?  I don't know what kind of shape its in.  

GM small block? ...Buick/Olds/Pontiac? ....Ford?...

GM small block? ...Buick/Olds/Pontiac? ....Ford?...Mopar?

sorry for resubmission

I;m guessing a small block Chevy 400?

Not a whole lot of value.  Some car guys will short stroke it into a 377.  Some trucks guys might take the crank and make a 383 out of a 350.  But for a run  on the mill 400, there's not a whole lot of value.

edited to add:  If you're considering buying it, price it the same as you would a used 350 - i.e. not much.

that's another thing, I don't know if it chevy, ford, buick, etc.  I'd say it is a chevy 400 though.

$50-$100  $125 at most depending on the shape of the bore etc. Now if it is a Pontiac, could very well be worth more, depending on what 400 it was used to build. Pontiac would probably go for more(not much more though)simply because original Poncho engine parts are getting hard to find. I hoarded like crazy and refuse to sell, even though I have not run a Pontiac engine in my Firebird in over 5 years. But, 400 Chevy's are a dime a dozen like the 350s.

More than likely is a Chevy. But easy way to tell difference between Pontiac and Chevy. Pontiacs are larger than smallblock Chevy no matter the cubic inches. Pontiac 326-455 are the same dimensions. But, Chevy distributor goes thru the manifold into the lifter valley directly, versus Pontiac has a distributor pad seperate from the lifter valley at the back of the block. Pontiacs use a seperate oil filter mount versus Chevy is part of the block. But biggest easiest is size, Pontiac engines are in between big block Chevy's and small block Chevy's as far as dimensions.

Which could also present another problem, no easy way to tell cubic inches on Pontiacs without proper documention, checking the numbers or measuring the bore. That and the timing chain cover doubles as a water pump housing on Pontiacs, which kinda gives it away too. There are bolt holes that are practically straight up and down on the face of the block versus Chevy is all seperate and kinda horshoes for the timing cover.

no easy way to tell cubic inches on Pontiacs without proper documention, checking the numbers or measuring the bore.

Pontiacs made after 1970 have the cubic inches cast into the side of the block and under the valley pan.

Quoted: no easy way to tell cubic inches on Pontiacs without proper documention, checking the numbers or measuring the bore. Pontiacs made after 1970 have the cubic inches cast into the side of the block and under the valley pan.

Really? I had no idea. That's interesting though for sure, makes feel like a jackass for all the research and measuring I did on mystery blocks I got.

Your looking to buy a block and you have no idea what it is? And yes a short block is the whole bottom end w/ crank, rods, pistons, etc. You are talking about a bare block. Since you seem to have no knowledge of engines I would recommend against you trying to build one. As the other guys have said Chevy, Ford and BOP have all used 400 engines.

Quoted: Your looking to buy a block and you have no idea what it is? And yes a short block is the whole bottom end w/ crank, rods, pistons, etc. You are talking about a bare block. Since you seem to have no knowledge of engines I would recommend against you trying to build one. As the other guys have said Chevy, Ford and BOP have all used 400 engines.

That is a very good point, I assumed you had experienced building engines. If you do not, do not attempt it yourself. Workwise, it is not difficult. But, making sure you have everything mic'ed correctly, machined correctly, torqued correctly and most of cleanliness is imperative. Then to have it run properly everything has to come together as a package. Cam, heads, intake, carb, ignition, exhaust, transmission, gears it all has to work together otherwise you end up with a dog.

Quoted: I know a guy who is selling a 400 short block.  Its just the engine block.  Anyone know how much it is worth?  I don't know what kind of shape its in.

I don't know where you are in Indiana, but down around Louisville the Street Stock guys are paying healthy for these motors.  It is getting to the point that you have to look to find one.
My .02.

you guys are right, I don't have any knowledge of engines.  I was asking because my dad and I are looking for a project car and we found one that came with an extra engin - a 400 short block.  Problem is the guy is asking too much.  We know what the car's worth, but not what the engine's worth.

My dad drag raced for 14 years back in the 60's and 70's,  built his own cars, and almost never lost a race.  He's always telling me when he gets the chance of how he rebuilt some engine and how good it ran after he worked on it, and how he worked on a buddy's car and how it ran so good after he worked on it.  I look forward to getting a project car so he can finally teach me all I ever wanted to know about how to work on a car.

If you want an engine to laern on, get a Chevy 350.  Even I can (and have) rebuilt those.  

Well if they want too much for the car and the block is the deciding factor pass on it. It is worth no more than $150 if that.

Well one of the biggest things and determing factor in price is whether it is a short block or bare block. If it is a short depending on how it is built it could very well fetch 500-1000 or more depending on what parts it uses etc. Stock Chevy bare block no more than $150, BOP a little more and Ford I have no idea. If it is a short block that has been built, it would just depend on what was used in the bottom end.

Lots more information is needed before any price determination can be made, because a difference in rotating assemblies, block prep, and what company made it makes a huge difference in price. What kind of vehicle is this in? That would at least help somewhat in what type of 400 it is, as long as they did not build a frankencar such as myself. Big block Chevy, BOP/corporate tranny, Ford rear end all in a Pontiac car using Camaro tail lights.