Difference btw Small and Big Block??

[The Stang GT]

Hey guys, i was wondering if anybody could tell me the difference between a small block and a big block....., and what exactly does a transmission brake do also???? Thanks......

 

[Dusstbuster]

Block size. Not sure where the transition is but it's the cubic inch measure of the engine I believe. I think I have an idea what a transbrake is but I'm not sure so I won't say something wrong. http://en.wikipedia.org/wiki/Transbrake <------transbrake
http://www.clubhotrod.com/t17266.html <---small vs big block

 

[Stan Weiss]

The difference is in bore spacing centerline. The small block Chevy is 4.400" and the Big block Chevy is 4.84. Whereas the Pontiac was a mid block with 4.62. The 281 has a 3.937 bore spacing centerline. I have a "engine, bore, stroke, rod length, ratio table" with the bore spacing for a number of engines on my web site. http://users.erols.com/srweiss/tablersn.htm