I read once that small blocks were under 400 ci and big were 401 and up. Now I hear people talking about a 427 small block.

I just don't get it.

 

It refers to the casting (engine design). In the old days the small block Chevys were the 265,283,327,350, etc.. and many more. They can be bored and stoked to all kinds of sizes. The big blocks were the 348, 409, 427, 454.. a different design. Things are different now with the 350 being a fresh design.

Fords and others have similar terminology.

And this thread probably belongs in Car Talk.

 

More engine combinations were made by using one motor's crankshaft in another motor's block. This was done by Chevrolet in the late 60's. They introduced a Camaro SS in 1968 that came with a 396. This was made by using a 427 block with a 350 crank(slight modification to the crank journals). Because the engine incorporated the 427 block casting, it was a "big block" motor.

 

A 427 small block is simply a 351 block bored out to 427 cubic inches...

You can stroke a 351 to various different types of cubic inch applications...ex 357, 396, 408, 427 ect...But, they are not big blocks, even though their cubic inches might suggest that they are...

Getting 427 cubic inches out of a stock 351 block is pushing it...Most people use the Ford SVO block when running this many cubic inches in a 351 based block...

Then you can always get a big block and de-stroke the motor, which is a totally different story and gets kind of confusing...

Personally, I think 408 cubic inches out of a 351 based block is about the most a person safely might want to go...I am currently building a 408 motor for my Mustang using a 351 based SVO block to handle the 250 shot of nitrous that will be going though it...

 

Just remember mice and rats. Mouse motors are made from the small block and rat motors the large blocks. I was reading an article months ago where some aftermarket engine builder was selling crate mouse motors with 427 displacement. That would confuse someone not familiar with the terminology.

 

When I was talking about the 427, I was talking about the one GM used in the Corvettes in the late 60s. That one is cast as a big block.

 

Wish I could fit one of those in the S

 

Not me ... too heavy

 

Why would you want to swap out the motor that I think is one of the leading technological marvels on the market today, for a 40 year old pushrod design? 120hp per liter or 55 with the Ford 427. Not to mention the weight the 427 would put on the S2000. A cast iron block with cast iron heads. Last time I checked, iron was slightly heavier than all aluminum.

 

Incubus you are pretty much right saying that most small blocks are under 400 cu. and big blocks are above 400cu. w/ a few exceptions. Chevy made a small block 400. Pontiacs used the same size blocks for v-8's. The 350,400,455 all had the same size block. This may of been the same for Buick too. The 427 used in the 60's vette was all aluminum I believe. I know they had a zl1 option for the camaro that was an aluminum 427 also.