How to distinguish big block from small?

[dremu]

Gonna go look at a truck which is alleged to have a 454 in it, but wanna make sure it's not had a 350 or something swapped in. Until now I've only dealt with SBC's ... is there some easy way to tell a BBC from a small, besides "it's bigger"? /forums/images/graemlins/laugh.gif

Seeing as I've managed to confused an NP203 for a '205 (twice!) I am less trusting in my sight than I used to be /forums/images/graemlins/laugh.gif I have the tranny patterns down so I can tell a TH400 from a 350, but I donno anything about engines.

-- A

 

[TrcksR4ME]

Valve covers, BB's have 7 bolts holding them on. Also the exhaust, the exhaust ports coming out of the heads are pretty evenly spaced, unlike a SB which the middle two are right next to each other.

 

[pauly383]

Exactly , totally right /forums/images/graemlins/waytogo.gif. This was in a supersize post and shows the valvecover bolts on the bottom and even exhaust spacing .

 

[k5freak44]

yea sb= o oo o
bb= o o o o

 

[big83chevy4x4]

one of my friends stopped by when i had just the block, heads, intake on my truck, everything else was out. he said, "wow that is a small block" /forums/images/graemlins/crazy.gif

what they said, and its bigger. /forums/images/graemlins/whistling.gif

 

[dremu]

woohoo! Thanks all!

-- A